Atriplex patula

Atriplex patula

Spear Orache, Spear Salt Bush

As I write this article, it’s August in the year of California’s third most severe drought. There’s not much out there in bloom. So I’ve retreated to one of the few places where plants are doing anything. Yes, I’m returning to the coastal salt marsh. That is where we found the plant to be featured in this issue of Obispoensis. It’s a plant that generally doesn’t get into wildflower books but does make it into many weed books. This is because it is weedy, widespread, and its flowers are green or brown and tiny and (in our area) fruiting is relatively rare.

The plant is Atriplex patula ssp. hastata or just plain A. patula depending on which plant ID book you’re using. In our area, Atriplex patula may have two subspecies which differ, according to some identification keys, primarily by their leaf shape. Subspecies hastata is the more common and distinctive of the two. Dr. Robert Hoover in his The Vascular Plants of San Luis Obispo County states that A. p. ssp. hastata is very common around the Morro Bay salt marsh. The other subspecies, A. p. ssp. patula, according to Dr. Hoover, is rare in our area. The only location he cites is nine miles north of Morro Bay. Subspecies patula produces leaves that are narrow, oblong or lanceolate; their bases are smooth and rounded and therefore lack any backward projecting lobes or acute projecting angles. The model for this plant grows along the uppermost edge of Morro Bay salt marsh.
You probably won’t get your feet wet if you would like it find it because it grows where it will get inundated only by the highest of tides, if at all.

Spear OracheA look at Bonnie’s drawing will show the distinctly arrow-head shaped leaf blades with their conspicuous backward projecting lobes on the outer leaf blade base, making the leaf resemble a spear point or arrowhead. This shape is technically termed “hastate” by botanists. The shape of the leaf gives it its subspecies name. However, if you look again at Bonnie’s drawing, you will see some leaves that are NOT hastate but would be at home in A.p. ssp. patula. I suspect that this is the reason why the new Jepson Manual doesn’t recognize subspecies in this species. It simply refers all forms to the species A. patula.

It is interesting that they retain the common name of spear saltbush or spear orache for all appearances of the species. A word about its leaf arrangement. Most of the descriptions indicate that it is alternate but a look at Bonnie’s drawing will show the plant drawn has paired, opposite leaves prominently displayed. Look at the drawing again, and you will also find alternating leaves as well. The most technical description I found stated “Leaves alternate except the proximalmost.” I’m not sure what “proximalmost” means.

According to The Jepson Manual, it may or may not be a native plant; but a survey of the web leaves little doubt that it is a recent introduction to North America. There are two common coastal salt marsh species of salt bushes found in or near the Morro Bay salt marsh. The other species, A. watsonii or Watson’s salt bush was the plant profiled in the December 2011 issue of the Obispoensis. The two salt bushes can readily be told apart with only a casual glance at their growth patterns. Watson’s salt bush grows in flat mats that can become mounded in the center. Therefore its branches are horizontal and parallel to the ground. Spear saltbush’s branches are vertical and thus can reach a height of a foot or more. Watson’s saltbush rarely reaches a height of 4-6 inches.

Some may have noticed that I have not identified the family to which salt bushes belong. This is because taxonomy texts (and most of the web entries) place it in the Amaranthaceae while The Jepson Manual places it in the Chenopodiaceae.

Classically, before DNA sequence data, salt bushes were placed in the goosefoot family (Chenopodiaceae). When the DNA sequence data and cladistic or phylogenetic classification methodologies became available, it was noted that genera of the mostly temperate zone Chenopods and the mostly tropical family Amaranthaceae came out together but were inconclusively separated in their phylogenetic diagrams.

For example see Kadereit, et al. [2003. Phylogeny of Amaranthaceae and Chenopodiaceae and the Evolution of C4 Photosynthesis, Int. J. Plant Sci. 164(6) 959-986]. This led many taxonomists to combine the two families into one. Since the Amaranthaceae is the older name, it had priority over the name, Chenopodiaceae. Therefore, if the two families are combined, then the Rules of Botanical Nomenclature require that Amaranthaceae be used.

The classical Amaranthaceae contains only four California genera (only one of them the very widespread — the weedy pigweeds, Amaranthus). In contrast, the classical Chenopodiaceae is huge in California. It consists of at least 17 genera and many species. Although most common in deserts, it is found in many other habitats as well. In other words, the classical Chenopodiaceae contains many species that dominate many habitats in California, whereas the classical Amaranthaceae are a relatively minor component.

This raises a question that has been raised many, many times before. What is the purpose of Biological Classification? When mutually exclusive, is its highest purpose to indicate phylogeny (evolutionary relationships) or is it to aid identification (ID)? Obviously it’s best when both purposes are in agreement! The authors of the Phylogeny paper admit that the phylogeny of the genera within two families is somewhat weakly supported, I think the editors of The Jepson Manual came down on the ID side of the question. I’ll leave all of you to determine who is right.

by Dirk Walters, illustrations by Bonnie Walters | Dirk and Bonnie Walters are long-time CNPS-SLO members, contributors, and board/committee participants. In addition to his work at Cal Poly, Dirk is the current CNPS-SLO Historian.

Native Plant Pest Control

With the drought extending into three summers now, many plant pests have taken advantage of the warm dry conditions. Even though California native plants are strong, hardy, and usually resilient, the lack of moisture has stressed them beyond their normal expectations. With this extra stress the plant’s ability to fend off insect infestations has diminished immensely, leaving many plants to decline to the point of no return. Keeping this in mind, I am going to give some suggestions about pest control.

First, pests hate water, so if you can, use water to wash down the leaves of infested plants. Second, soaps such as Dawn dishwashing liquid non-bacterial formula can smother insects such as aphids, red spider mites, and scale. (I use 1 tsp. per quart of water.) Lastly, for severe infestations, I use neem oil which can work as a insecticide and/or a fungicide. It comes from a plant (Azadirachta indica) so it is a non-petroleum based oil. Follow the instructions on the label.

Hope to see you at the next meeting.

–John

Calandrinia ciliata

Calandrinia ciliata

Red Maids

Bonnie’s drawing for this issue of Obispoensis is of a plant that is found throughout the western United States as well as spreading north into British Columbia. It has also been recorded in a couple of South American countries. It is especially common in coastal California. It is generally given the common name of red or pink maids (Calandrinia ciliata) although I’ve also seen it called fringed red maids and desert rock purslane on the web.

Although common and displaying easily seen bright pinkish-red, or is it reddish-pink flowers, it is often overlooked. This is because it tends to grow with its leaves and branches flat against the ground or flat against  surrounding plants. One sees it best when looking straight down on it. This is how the photo was taken upon which Bonnie’s drawing is based. The flower in the picture has its stamens just emerging from deep in the flower. It also has to be admitted that Bonnie’s drawing portrays a phase in the life of this wildflower that is fleeting.

What has been drawn is only the initial tight spiral cluster of leaves attached to a stem less than ¼ or so inches tall. Botanists call this a basal rosette. In order for the next statement to make sense, one must remember that stems grow longer only from their tips. This growth point contain cells capable of dividing to produce more cells that can then differentiate into the various types of adult cells. (They are called stem cells in animals such as humans). This region is called the apical meristem.

In the plant drawn, the apical meristem has produced a single, just opened flower. Flowers are genetically limited to parts that are set in size and shape; once they attain that configuration they stop growing. If this is true, then the central axis of the rosette is blocked from growing taller. In order for a plant to expand, it must produce branches from the lateral meristems (found in the upper angle between leaf and the stem to which it is attached). Unlike the initial vertical rosette axis, these branches grow out horizontally and the leaves are produced far apart. Additional flowers can be produced along the sides of these branches in an arrangement (inflorescence) called a raceme. Oh, I suspect it goes without saying that these secondary branches can themselves produce more branches.

David Chipping and I had never seen this plant produce a carpet of color visible from a speeding car until this year. It was a fallow field. The color was so different from anything we had ever seen. We had to stop and take a closer look. It was a carpet of red maids. I suspect that it was able to grow in such profusion due to the drought. All the larger, showier plants were either absent or extremely stunted.

Red maids is a native plant, but it is one that actually thrives with a little human disturbance. For this reason, it
is also classified as a weed, but only a slightly nuisance one.

Some might wonder why I haven’t mentioned to which plant family red maids belong. This is because there has apparently been a recent change. In ALL my “older” reference books this species is listed in the purslane family or Portulacaceae. This family contains miner’s lettuce and the beautiful Lewisias. The old Portulacaceae was easily characterized by its only two sepals and + succulent leaves. But the new Jepson Manual recognizes all the California genera but one (Portulaca – true purslane) that were in the Portulacaceae to be now in the family Montiaceae. None of my plant taxonomy references recognize the Montiaceae so none of them indicate how to distinguish the new family from the old one. A quick perusal of the keys in The Jepson Manual did not yield any obvious distinctions. Why was the Montiaceae separated out? In systematics, any recognized taxon (order, family, genus) should be derived from a single ancestor. Such a taxon is said to be “monophyletic.” However, modern classification procedures called cladistics indicate that the genera of the old Portulacaceae separate into different clusters with different ancestors. Such a group is said to be polyphyletic and is a no-no! Unfortunately many characters used to produce modern classification systems are not readily apparent in the field or even without a well equipped laboratory as they are DNA or physiologically based.

Consistent with its weedy designation, red maids would be expected to be found in disturbed ground. And this is where it is most often found. It is especially common after fires and along trails. And, as mentioned above, it is not adverse to growing in human created fallow fields and other agricultural lands.

by Dirk Walters, illustrations by Bonnie Walters | Dirk and Bonnie Walters are long-time CNPS-SLO members, contributors, and board/committee participants. In addition to his work at Cal Poly, Dirk is the current CNPS-SLO Historian.

 

[See also:

http://vnps.org/princewilliamwildflowersociety/botanizing-with-marion/spring-beauty-claytonia-virginica/

http://www.zora.uzh.ch/42651/4/Nyffeler_Taxon_2010_V.pdf
—ed.]

Spring Wildflowers at La Purisima Mission

Wildflowers at La Purisima Mission

“A Surprisingly Good Display of Spring Annuals”

In spite of a very dry year, the March rains brought out a respectable display of spring annuals in some of the meadow areas on the La Purisima Mission grounds.

On Sunday, April  6, 2014, Connie Geiger and I led our annual early April field trip of around 25 people, this year along “Al’s Flower Trail,” named for Al Thompson, for many years the main Garden Docent at the mission. This trail runs along a slope on the northeast side of the valley, starting from a cistern by a stand of coast live oaks, and meets the trail running along the creek to the “duck pond,” the source on the early water system.

Wildflowers Viewed

White flowers included white layia, Layia glandulosa, popcorn flowers, Cryptantha & Plagiobothrys, spp., common yarrow, Achillea millefolium, honeydew (AKA wedge-leaved Horkelia) , Horkelia cuneata, miner’s lettuce, Claytonia perfoliata, California croton, Croton californicus, and morning-glories, Calystegia spp.

Yellow flowers included dwarf golden yarrow, Eriophyllum pringlei; golden yarrow E. confertiflorum, Bigelow’s coreopsis, Coreopsis bigelovii, and assorted DYCs.

Blue to lavender flowers included various Phacelia spp.

Red to pink flowers included purple owl’s clover, Castilleja exserta, prickly phlox, Leptodactylon californiacum, purple Chinese houses, Collinsia heterophylla, among others.

There were bush as well as forb lupines, including silver bush lupine, Lupinus albifrons, costal bush lupine, L. arboreus, dwarf lupine, L. bicolor, and collared lupine, L. truncatus. Along the left side of the trail, were several sand almonds, Prunus fasciculata var, punctata, some in fruit.

At the head of the trail were several stands of cream cups, including the carnival poppy (a color variation alternating
white and yellow petals), Platystemon californicus. Down the slope towards the creek was a stand of goldfields, Lasthenia sp. By the trail up to the cross, were a few black figworts, Scrophularia atrata, and some redberry bushes, Rhamnus crocea, with tiny flowers.

All in all, a very rewarding tour.

– Charlie Blair

April, 2014

 

Valley Oak Snag

We are going back into the archives for this cover of Obispoensis. The landscape is a drawing of the Shell
Creek area that Bonnie drew for the December 1991 cover. The inset is an ID drawing of the leaves and acorn of the valley oak. Why would one want to combine these two pictures? What is the relationship between the two images? What follows is a short history of my encounters with the valley oak tree that became that snag.

I first encountered what was to become the snag in the spring of 1970. As can be seen from the drawing, it stood all by itself in a grassy pasture field. The field is near the junction of Highway 58 and Shell Creek Road. The base of its trunk is drawn showing that it was surrounded by various grass species while the space beyond its drip line (shown empty in the drawing) contained carpets of wildflowers.

The difference in plant species under the tree from that away is due to what has been termed “canopy effect.” Its cause is probably due to the tree, when it was alive, being able to bring water and dissolved minerals up from deep in the soil. Since the tree was somewhat inefficient in using all it brought up, some of these minerals got deposited on the outside of the leaves. This “waste” was washed or dripped off the leaves onto the ground below. Note that the canopy effect persisted several years after the tree had died, so shade was probably not a major factor.

This canopy effect was especially evident when I first encountered the tree in 1970 — the 2nd spring after the record rainfalls of 1968-9. We don’t have any record of the living tree except memory. As can be surmised from the drawing, the tree had died and become a standing snag by December 1991. It fell over sometime
in the late 1990s or early 2000s. After it fell down, the “smaller” branches were harvested for fire wood. But the trunk and bases of the larger branches were so massive that they were not deemed worth the effort to harvest.

Here is a picture of the snag today. Valley OakI have visited the snag a number of times over the years. It might seem criminal to let all that wood go to “waste,” but I assure everyone that it is not going to waste. In the years just after it fell over, it was inhabited by termites. These were not in evidence this year probably due to the drought, although I didn’t break into it to check. However I did notice that it is being used as a roof by animals burrowing under it.

The inset is Bonnie’s drawing of Quercus lobata leaves and acorn drawn in 1981. Quercus lobata (Fagaceae) is
commonly known as valley oak, California white oak or roble. The last name (roble) was used locally in the name of city, Paso Robles or more correct, Paso de Robles, which translates valley oak pass. Any one who has traveled north on 101 will note that valley oaks are common around Paso Robles and that the city sits in a valley between two high ridges.

I will recite a few notes on valley oaks. They are the largest of our California oak trees. The trunk in the picture above is over five feet in diameter. Valley oak is a true California endemic as its natural range is restricted to the valleys and low hills surrounding the Central Valley and Inner Coast Ranges. Its acorns mature in one year and were used extensively for food by native Californians.

Because the species prefers to grow in deep, fertile valley soils, it has been severely decimated by agriculture. One reason for it current survival numbers for adult trees maybe attributed to its massive size. It was easier to plow or graze around it than to cut it down.

Unfortunately acorns and seedlings are eaten by cattle and rodents, so (as was reported in the current issue of Madrono Volume 61(1) 1-8), there has been little recruitment of new trees. The cause for this lack of survival (recruitment) to older seedlings and saplings is still controversial. I suspect several causes will be ultimately determined. The paper noted that, in their study, lots of seed and early growth seedlings were found. What ever the cause, it also effects blue oak (Quercus douglasii) which is often found upslope from valley oaks.

by Dirk Walters, illustrations by Bonnie Walters | Dirk and Bonnie Walters are long-time CNPS-SLO members, contributors, and board/committee participants. In addition to his work at Cal Poly, Dirk is the current CNPS-SLO Historian.

Salmon Creek Trail, Cambria

Salmon Creek Trail Wildflowers 2014

Here’s a list of wildflowers seen along Salmon Creek Trail on April 10, 2014, submitted by Amanda Darling

Note from Amanda:

There is still a good amount of wildflowers even after the dry winter 🙂 I hope this information is useful.

Thank you for your efforts,

Amanda Darling, Cambria

 

columbine (at San Carpoforo)

shooting star – dodecatheon

allium – brodaea?

white star – zygadene

vetch

lupine

strawberry

blackberry

(another berry with broad yellow-green leaves)

iris

indian paintbrush

chocolate bells

buttercup

morning glory

blue eyed grass

purple nightshade

————————————-

 

 

In Memory of Las Pilitas Nursery founder Bert Wilson

In Memory of Bert Wilson

It is with great sadness that we must report on the passing of Las Pilitas Nursery founder and legend Bert Wilson. The California native plant community has lost an extremely valuable member.

Bert had a huge influence on our knowledge and our gardens. The Las Pilitas  website is the go-to site for information on California native plants and many of our gardens are full of plants from the nursery. Those of us fortunate enough to have had personal communication hold him in very high regard. A bit of his passion and dedication will live on in the many people he reached.

We extend our sympathy to Bert’s family — Celeste, Penny, Ian and Valerie. May we offer these Bert-isms from the CNPS-SLO community as comfort in your time of loss.

Notes From Our Community

I always enjoyed my time at the chaos of that nursery. He always extended me the greatest and broadest invitation to roam about the beds looking for overlooked treasures. I would take the long way over the La Panza summit and down the Pozo Road, just so I could swing by the nursery.

Bert took time with even the least experienced, to educate them. I remember showing up with a teacher who wanted to landscape a school with natives; Bert gave a curt “Plant Coyote Bush, so at least something will survive.” But it was just to judge our commitment, and once he softened us up, he loaded us up with plants and rarities.

I believe on his favorite subject of soil micro-ecology and symbionts, his promotion of native microrhizae changed California restoration. Even tomatoes are being grown with specialized soil microbes by gardeners such as Ralph Johnson that tell me they first learned about micro-ecology from Bert’s website and frequent discussion.

I don’t know all of his introductions to horticulture, but “Powerline Pink” (Salvia spathacea) and Pozo Blue are favorites of mine and have inspired me to turn a keen eye to finding selections in our native flora. He actually tested fire resistance of chaparral shrubs and likely saved enormous swathes of landscape by being able to defend keeping the species that are far more fire resistant than the dry grass firebreaks that were promoted to replace them. His website, hundreds of pages, has been a go-to site for real horticultural tips for a decade. -John Chesnut

 

What a loss! Bert was one of the founders of the Wildflower Weekend that was such a success for many years. -Dave K

 

Bert was a marvelous resource about native plants when no one else knew about them. I have every one of their catalogs since they started out and I learned so much from my visits to the nursery, the websites and their catalogs. The visits were a hoot. Even if Bert didn’t want to sell one of his babies to you because you lived in a zone where it wouldn’t thrive, Celeste would sell it while he went off grumbling. I remember so many visits where he showed off his newly grown babies and was so proud of them. He had character, he was a character, he was memorable and I learned so much from him. -Heather

 

I have been going out there for maybe forty years now and was there again a few weeks ago and I have always appreciated having the California natives that are available the Las Pilitas Nursery. Penny is now doing an amazing job out there, along with her mother. Bert Wilson’s work has had a big influence throughout the state. -Mardi

 

Bert was always so generous to me with his time and advice when I called asking questions. -Susi

 

I think we all have “Bert stories.” In our case, he was the only nurseryman who figured out what would grow on the abominable soil found in the area where we live in SLO and that he did from his property without visiting the site, 50 miles away. Bert called it “yellow clay” and recommended ten different species which all have managed to survive when everything has not. He took the time to listen to our stories of woe and come up the perfect answer, while everyone else we had asked at the time had no clue. That’s real intuition! -Bill Waycott

 

Erodium moschatum

Erodium moschatum

Filaree

Erodium moschatum & E. cicutarium

I assume it is not news to anyone that California in general and the Central Coast in particular has been experiencing an extreme drought. That means that most native plants that are adapted to this situation have been in waiting mode and are not doing much of anything. One ecological category of plant that seems to be able to grow under these extreme conditions is the weeds.

What is a weed?

The best definition I know is “a plant adapted to the disturbed conditions caused by humans or their livestock.” By the way, 7+ billion humans and their livestock currently make up 98% of mammalian biomass. This is up from 0.1% at the beginnings of Agriculture some 9,000 years ago. Human habitats include yards, vacant lots, crop fields, pastures.

I suspect all of you have your own favorite definition of a weed. Bonnie came up with a new definition for a weed while she was working on the drawing for this issue of the Obispoensis. She noted that “a weed just says thank you when you put a sample in a cup of water and continues to grow as if nothing important has happened, whereas native plants tend to begin to wilt even before you can get them into water.” Weeds have a high tolerance for adverse physical condition, but most usually do not tolerate competition from other plants.

Filaree belongs to the lowest classification given to weeds as it pretty much stays out of little-disturbed native vegetation. The two species of plant discussed this time are members of the genus Erodium. They are E. cicutarium (coastal heron’s bill, red stemmed filaree, red-stem filaree, red-stem stork’s bill) and E. moschatum (white-stem filaree).

Identifying Filaree

Filaree illustrationThe illustration  is a composite of Bonnie’s new and old drawings plus an additional digital scan. The large central drawing is of a whitestem filaree that was growing under crowded conditions. Note that most of its largish compound leaves, which are attached to the stem just above the root, are orientated nearly vertically. Contrast this with the scan of the red-stem filaree that was growing in a totally open habitat without nearby plants. It has its leaves lying almost flat on the ground. This is how all filaree species (including red-stem filaree) orientate their leaves when they grow in the open.

Where to find Filaree

The two filarees are found everywhere along the coast wherever humans or their livestock have modified the land. Prize winning gardeners will keep them at bay, but not ordinary people.

These species are also found in disturbed ground in the interior, but there they are likely to share the ground with several other species of filaree. All these other species (E. texanum, E. macrophyllum, E. botrys, and E. obtusipicatum) have simple leaves. E. botrys is also to be expected along the coast.

Early Classification with Geranium

When Carl Linneaus first described the filarees, he put them in the genus Geranium. Later Geranium was split into three genera (Erodium, Geranium and Pelargonium) based on the number of male structures displaying fertile or pollen producing anthers. There are five in Erodium, seven in Pelargonium, and ten in Geranium. The rest of the flower, sepals, petals and female containing structure, gynoecium, differ only quantitatively among the three genera. There is a generalized flower and gynoecium included in the illustration. These are from an early edition of Dr. David Keil and my Vascular Plant Taxonomy text.

Common names

Of particular interest is the gynoecium. Note the bulges at the bottom. These contain the actual seeds. Then there is the very long central portion (style) that resembles a bird’s beak. It is this structure that leads to the common names that have been applied to these plants, i.e., heron’s bill and stork’s bill.

Seed Dispersal

When the seed is mature, the gynoecium begins to dry out. As it dries, it splits vertically into five parts. Each part contains a basal seed-holding portion attached to its elongate portion of the style. When fully dry, the style portion begins to coil upward with increasing speed. By the time the coil and seed have reached the top of the style, it has enough momentum to be flung into the air and away from the parent plant. Most of them will land several inches beyond the reach of the parent plant. This is the sweet zone for seed dispersal. It is far enough from the parent to prevent competition but close enough to still have a similar environment. Dispersal over long distance is very risky because the probability of a seed landing in a favorable habitat approaches zero.

Long distance dispersal among weeds is contrary to this thinking. We carry weed seeds with us and when the seed falls away from us, where is it likely to land? It will probably be in another human-dominated environment.

Oh, by the way, after the seed-style complex lands on the soil, the style portion continues to expand and coil with changes in humidity. This allows for the seed to be pushed along the soil surface for a secondary dispersal. It also can serve as a “drill” to bury the seed in the soil.

Are Filaree California Natives?

Our two common coastal filarees are not native Californians. Like most of us, their ancestors came from Eurasia. When they arrived is uncertain as they were already here when the first botanical surveys were done. When I first arrived in California I was easily persuaded that native California plants were great and the rest were terrible weeds. When I made the mistake of saying, “isn’t it a shame that there is so much filaree in this pasture,” in the presence of a rancher, the rancher quickly turned on me. He said in essence, “Thank God for filaree! It is what makes my operation profitable. Cattle (and guinea pigs) love it; it is one of the first plants to appear in the pasture in the spring and it continues to be present throughout the grazing season.” I haven’t been foolish enough to bad-mouth filaree since. Both species of filaree are not only good forage for cattle, but they also are good for human grazing as well; the web tells of people using the young spring leaves like parsley in salads and the roots in various medicinal ways.

There is one last item about filaree. It can be so numerous in grazed pastures of the interior that they can produce what appears to be reddish-pink haze coating the ground. Look for it mid-morning when they are in full bloom. You might also try to imagine how many flowers it would take to create that haze.

by Dirk Walters, illustrations by Bonnie Walters | Dirk and Bonnie Walters are long-time CNPS-SLO members, contributors, and board/committee participants. In addition to his work at Cal Poly, Dirk is the current CNPS-SLO Historian.
Vernal Pool with Downingia

Vernal Pool with Downingia

Vernal Pools occur where there is moderate to large sized “natural” depression with no outlet. The depression has to be large enough to capture enough rainfall to fill the pond to some depth. The water collects in the lowest point in the depression. There also must be an impervious layer under the pond that prevents the water from seeping deep into the soil. This impervious layer is usually a layer of calcium carbonate that forms where water seeping downward due to gravity is balanced by pull upward caused by evaporation. True vernal pools are a desert or semi-desert phenomenon. I suspect it goes without saying that not all temporary pools are vernal pools. For example, in San Simeon State Park there are extensive interlocking shallow pools surrounding small hillocks that are filled up by winter rains and are gone by summer. These are formed by animals that dig out the depressions and pile up the excavated dirt to form the mounds. This allows the animals a drier den during the rainy season. Back East, where it rains or snows most of the year, you will find temporary ponds that will last from many months. These are colonized by ordinary species more or less identical to those that inhabit the forest around them. Vernal pools will only last anywhere from a few days to a few weeks depending on their size and the amount of rainfall.

For the second Obispoensis of this year, we are doing a repeat of a drawing Bonnie did for the banquet cover back in 1993. We’re repeating this particular drawing because of the drought and in the hope that it will serve as sign that we really, really need rain! It was originally done in honor of Dr. Wayne Ferren’s (then Curator of the Herbarium at U.C. Santa Barbara) program entitled “Creation and Restoration of Vernal Pools at Del Sur Reserve near Isla Vista, California.” The vernal pool in Bonnie’s drawing is one that occurs off the road to leading to Cerro Noroeste from California State Highway 166. It is on a shelf in the otherwise steep slopes of that mountain’s foothills. This particular pool is a favorite stop for CNPS-SLO, especially when there has been enough rainfall to fill it.

It is when the vernal pool lasts for weeks that they become particularly interesting. For plants, vernal pools are a particular challenge. The first plants to appear are those that can stand total emersion in the water. These are aquatic plants that usually live totally submerged in the water. Because the water is going to last for a very short time, these aquatic plants must have an accelerated life cycle to get from germination to fruiting. As the pool begins to dry up, plants that can tolerate saturated soils begin to germinate in a ring just inside and upslope from the water’s edge. Again these plants have a difficult environment. They begin life with too much water and end up high and dry as the pool constricts away from them. The end result of this process is a series of bands produced by various species that get their start under different soil water conditions. This banding is easily visible in Bonnie’s drawing. One genus that is particularly typical of vernal pools Downingia. It is they that form a spectacular bluish band around the pool. Bonnie included a drawing of the flower of the common Downingia species found in this particular pond. It is Downingia cuspidata.

Bonnie’s drawing was taken from a photograph, lost many years ago, that was taken on a chapter field trip to Mount Able and Mt. Pinos. Although the person shown in the drawing is drawn much too small to be recognized, notes from the time indicate that it is Sybil McLeod who served CNPS-SLO chapter in many different ways. Yes, she was also the wife of Dr. Malcolm McLeod who was a past CNPS-SLO President, Historian, and for many years the Rare Plant Committee Chairman. To be a committee chair in this chapter usually means you do all the committee’s work.

by Dirk Walters, illustrations by Bonnie Walters | Dirk and Bonnie Walters are long-time CNPS-SLO members, contributors, and board/committee participants. In addition to his work at Cal Poly, Dirk is the current CNPS-SLO Historian.
Mystery Manzanita in the Elfin Forest

Mystery Manzanita in the Elfin Forest

All three of Bonnie’s drawings this time are of manzanitas. One is a repeat of the endemic rare plant commonly known as Morro manzanita or Arctostaphylos morroensis. As you will see, it is included here to serve as a basis of comparison.

The other two drawings are new. One is of a single manzanita plant (maybe a clone) that grows near the mouth of Turri Creek where the Elfin Forest group’s 3rd Saturday Natural History Hike goes when it visits the salt marsh. It is currently in flower. The last is of a species commonly called, dacite manzanita (A. tomentosa ssp. daciticola). It grows nearby in the hills above the mouth of Turri Creek.

There are two other manzanita species that could also complicate the identification of our mystery manzanita. The first and most problematic is Oso manzanita (A. osoensis). Its recorded range is further away from our mystery, but still in the Turri Creek drainage. It is recorded as occurring on higher ridges and plateaus west of Hollister Peak on sandstone or dacite outcrops.

The last possibility is the Arroyo de la Cruz manzanita (A. cruzensis). It is this species that our plant would be if we used Robert F. Hoover’s 1970 edition of The Vascular Plants of San Luis Obispo County, California, for identification because it is the only species (other than A. morroensis) recorded for the area. Dacite manzanita and Oso manzanita were not recognized by Dr. Hoover as valid names.

So which name should we apply to our unknown manzanita? All who have attended these hikes readily concluded that the new manzanita is NOT the Morro manzanita. So if it is not Morro manzanita, what manzanita is it? This question, it turns out, is not easy to answer. This is where the third manzanita drawing comes in. It represents the dacite manzanita (Arctostaphylos tomentosa ssp. daciticola) which is one of two species found growing on the dacite, a granite-like rock which is dominant rock making up the Morro Sister Peaks. Outcrops of this rock weather into thin, infertile soils.

Dacite manzanita is found only within the Turri Creek drainage. I assume most will agree that, if our unknown is not Morro manzanita, it shows a much closer, but not perfect match to the dacite manzanita.

The identification of manzanitas is not easy. First, there are many species (60+ and many subspecies and varieties) recognized as growing in California. Second, I suspect all who have even a passing familiarity with California native plants can identify a manzanita. This means the genus has an easily recognized set of characteristics. It also follows that telling its many species apart is going to be a challenge because species characters must be of necessity minutely different or technical in nature.

However, they can be divided into groups based on the length of their leaf stalks (petioles) and the shape of the leaf blade base. One group, which includes the Morro manzanita, has an easily seen but short (< 4 mm) leaf stalk (petiole) and a smooth, rounded to chordate blade base. A chordate leaf base is going to resemble the top of a valentine heart. The other group has petioles either absent or so short (< 2 mm) that they would not easily be seen unless one looks carefully. Their leaf bases also resemble the top of a valentine heart (chordate). Neither of these traits is present in Bonnie’s Morro manzanita drawing which was probably based on a plant from Montana de Oro State Park. But they are found in the other two drawings.

There are other technical attributes of course, but most of these are not visible without a microscope or hand lens. One character that does not require a microscope, but does require some “digging” is whether or not a manzanita produces a large swelling at the junction where the root turns into the base of the stem. In those that don’t produce the swelling, which includes the Morro manzanita, branching doesn’t usually begin until the main stem (trunk) is a few inches or more, sometimes up to a foot or more, above the ground surface. These are called tree manzanitas due to that single trunk.

Those that branch from the swelling below ground are commonly called shrub manzanitas. Manzanitas that produce this structure tend to form their first branches below ground which produces a bunch of stems in a tight cluster. Again this trait should eliminate the Morro manzanita from consideration because it usually begins to branch at or above the soil surface.

So if it is not Morro manzanita, which of the other manzanitas is it? The Arroyo del la Cruz manzanita, as currently defined, should range from Cambia northward. The Los Oso manzanita is reported to be a relatively tall shrub (3 to 12 feet) and is reported to be restricted to dacite or sandstone outcrops. The dacite manzanita occurs just up slope from our mystery manzanita but is also supposed to be restricted to dacite outcrops. Our mystery manzanita grows on a relatively narrow terrace well above the salt marsh and just below the foundation fill used to raise South Bay Boulevard above the Morro Bay estuary. It is growing in coarse sandy soil probably derived from the fill. It is growing with species characteristic of coastal scrub with a large compliment of weeds. That is, it is growing in a classic, disturbed, man-made habitat. Such habitats are known to allow unusual individuals such as hybrids to occur out of typical range or habitat and become established. In other words, range and habitat can’t be used to limit the possible ID.

So what is its correct identification? I’m still quite unsure. Even the Cal Poly Herbarium is not much help here. I think I could find all three possible species among the specimens within each single species folder in the Cal Poly Herbarium. I do have to admit that the differences among the three short petiolate, chordate leaf-based species depends on the often subtle nature of the kind of hairs (pubescence or trichomes) found on twig and leaf. As stated earlier, these traits require at least a hand lens to observe. I think it is safest to leave it as a mystery manzanita. Maybe, a Cal Poly Senior Project or Masters student will take on this project and find the correct answer for us.

It appears that all the species from the Turri Creek drainage are closely related, at least based on appearance. With additional modern taxonomic techniques maybe it may even be determined that Dr. Hoover was correct back in 1970 when he concluded that all (except Morro manzanita) are the same species.

P.S. After writing the preceding paragraphs, I went back out and observed the three pictured manzanitas again. This time I walked through the Elfin Forest to reacquaint myself with the variability found among Morro manzanita individuals. The plants along the Board Walk are similar to Bonnie’s drawing. But if you observe the manzanitas along the Habitat Trail that goes off the north-east curve and goes toward South Bay Boulevard, you will find that the Morro manzanitas get shorter and shrubbier and their leaves have shorter petioles and more deeply lobed leaf bases. It’s a mini-cline. In other words they begin to resemble more and more our mystery manzanita. So, I’m forced to conclude, at least tentatively, that our unknown manzanita is simply an extreme form of Morro manzanita. If so, it may be the most northern individual of the species. I conclude this in spite of all of us assuring ourselves that is was clearly different from the Morro manzanita we all had pictured in our minds. I still think there is a good student project here, however.

by Dirk Walters, illustrations by Bonnie Walters | Dirk and Bonnie Walters are long-time CNPS-SLO members, contributors, and board/committee participants. In addition to his work at Cal Poly, Dirk is the current CNPS-SLO Historian.
Cynodon dactylon

Cynodon dactylon

Bermuda Grass

It’s November in a very dry year which was preceded by a dry year. Most native plants are waiting for the rains. The small amount of rain that fell in the last week in October I doubt will be considered significant, i.e., sufficient enough to initiate plant growth. So Bonnie and I have punted on the selection of the plant profiled in this issue of the Obispoensis. We have chosen to make a scan of an all too common grass which is generally known as Bermuda grass, Cynodon dactylon.

According to Wikipedia, it has lots of common names in many different languages. Gardeners often refer to it as devil grass when in mixed company. I suspect they use more colorful language when they are trying to eliminate it from their lawns and gardens. The common name, Bermuda grass, reminds us not to depend on names to give us accurate information. Yes, Bermuda grass does grow in Bermuda, but it also grows throughout the warmer parts of the world. It grows on every continent that has areas where periods of low temperatures are rare or of very short duration. In the U.S. it is found in almost every one of the lower 48 states. It is especially common in the warmer half of the country.

Where does Bermuda grass come from if not Bermuda? It has at least three other wild varieties and all of them, including the wide-spread variety, Cynodon dactylon var. dactylon, are found in South-East Africa. Only C. d. var. dactylon has a worldwide distribution.

It was probably introduced to the U.S. in the 18th century, whether as a lawn grass or for forage crop is not clear. The species is able to survive long periods of drought by simply “dying back” to its extensive net-like system of rhizomes (horizontal underground stems). Aerial shoots can arise from any of its multitude of nodes (region of stems that produce leaves and buds). It is this capability to form long and extensively branched rhizomes that explains its use as a lawn grass. However, its weakness is its habit dying back during drought. This means that one’s nice green lawn will have brown spots or, if a Bermuda grass lawn, turn completely brown during the dry season.

Bermuda grass also doesn’t share an area well — it is extremely aggressive. In experiments where Bermuda grass is grown with various other herbaceous species, it inhibits the other species. In some cases Bermuda grass growth is better when paired with other species than when it grows alone. Needless to add, its aggressive growth is why gardeners refer to it as devil grass.

Where there is adequate water, Bermuda grass puts much of its growth into its green aerial shoots which makes it an almost great pasture grass. Why “almost great?” It is because, under some environmental conditions, livestock poisoning has been traced to it. The species is a prolific pollen producer so it is a major cause of discomfort by allergy and asthma sufferers.

I hope it goes without saying that Bermuda grass is not a California native and must be considered a noxious weed! It is most common in disturbed, vacant lots and poorly maintained lawns throughout the human dominated portions of our chapter area. It can also be found on roadsides and dryer edges of streams and salt marshes or wherever woody plants are widely scattered. It does seem to behave itself because it doesn’t seem to compete against trees and shrubs very well. It does not spread into native plant areas as it is intolerant of shade.

The scientific name, Cynodon, is derived from Greek and means “dog tooth.” The dog teeth are the distinctive small scale-like leaves that arise from the nodes of the rhizomes. Dactylon is also from Greek and refers to finger- like structures. In this case it refers to the usually 4 or 5 thin inflorescence branches which somewhat resemble the fingers of a human hand with the fingers widely separated.

by Dirk Walters, illustrations by Bonnie Walters | Dirk and Bonnie Walters are long-time CNPS-SLO members, contributors, and board/committee participants. In addition to his work at Cal Poly, Dirk is the current CNPS-SLO Historian.

Monkey Flower

A new species of monkey flower discovered in the Sierra Nevada!

Mimulus filicifoliusI am the editor of Madroño, the Journal of the California Botanical Society. In the most recent issue Jay Sexton, Katie Ferris, and Steve Schoenig, published their discovery of the fern-leaved monkeyflower (Mimulus filicifolius). It’s a new species with finely divided, bi-pinnately compound leaves found in the northwestern Sierra Nevada where it occurs mostly on ephemeral seeps in rock outcrops.

Mimulus filicifolius is highly restricted, known only from Butte and Plumas Counties within the Plumas National Forest, and should therefor be considered in future conservation strategies.

As new botanical discoveries like this one are made, revised treatments for the Jepson Manual will be published online at the Jepson eFlora.

− Matt Ritter

Mimulus filicifolius map

 

Dendromecon rigida

Dendromecon rigida

Bush Poppy

A funny thing happened while Bonnie and I were working on the drawing and article for and about the plant discussed in this issue of Obispoensis. Before we started, we consulted Dirk’s list of past drawings and could not find any entry for Bush Poppy, a.k.a., Tree Poppy, (Dendromecon rigida). But after Bonnie was well into the drawing and I had started the article, we discovered a drawing and article from April 1995. We decided to go ahead and complete the ‘new’ drawing and possibly update what was said about Dendromecon back in 1995.

Bush poppy is one of the more common and easily recognized of our local shrubs. It is a woody member of the poppy family (Papaveraceae) and is especially common in our scrub communities (chaparral & coastal scrub) after fires. I’ve observed scores if not hundreds of plants per acre the first year after a fire. However, as the community matures, bush poppies begin to die out and become restricted to disturbed areas such as road cuts and trail edges. It is for this reason as well as its large conspicuous yellow flowers that this species actually appears to be more common than it actually is.

The poppy family is characterized by sepals being shed when the four petals expand (caduceus). Note that the spherical structures in Bonnie’s drawings are flower buds and not fruits. The superior ovary is long and thin. There are two very short styles which end in two large, flat stigmas. These can be seen in the drawing of the flower as well as the small aborting fruit found among the leaves in the 1995 drawing.

The ovary contains many seeds which are attached to two areas on opposite sides of a single cavity (i.e., parietal placentation). Each small seed contains a small fleshy body near the attachment of the stalk (funiculus) attaching it to the ovary/fruit wall. In the process of the capsule explosively splitting from the bottom up, the seeds are thrown away from the plant. After the seeds land on the ground, ants collect the attached fleshy body (aril) and carry them back to their nests. When the ants arrive back at the nest they either remove the seed from the aril before taking the aril into the nest or later. If the seed is removed later, it is taken out of the nest and thrown into the ant colony’s refuse heap. Either way, ants are very important in seed dispersal of this poppy.

Our local species is Dendromecon rigida which is common throughout most of the southern California mainland extending in to northern Mexico. A second species that is very similar to D. rigida is found naturally restricted to a few of the Channel Islands. This is D. hartfordii or the Channel Island tree poppy. This rare species differs from the more common mainland tree poppy by having larger flowers and shorter, fatter leaves. Lastly, the mainland tree poppy has minutely toothed leaf margins where as the island form has completely smooth margins. It appears that I may have misidentified the species in Bonnie’s 1995 drawing as the twig in the drawing as its leaves are drawn shorter and wider than her current drawing which is based on local SLO County plants.

One might expect that a plant with such large and showy flowers would have a significant following among California native plant aficionados. Also, we would expect the island bush poppy to be the preferred species as it has larger flowers, and this is often the case. However, Dendromecon is not commonly found in the home garden because it is particularly devilishly hard to get started. According to internet entries as well as Bornstein, Fross and O’Brien’s California Native Plants for the Garden (2005), its roots are especially sensitive to disturbance. According to Dara E. Emery’s book, Seed Propagation of Native California Plants, growing it from seed requires either a fire treatment or stratification (buried in between layers of moist sand) for 1½ months with a daily temperature fluctuation of between 46oF and 70oF. Mr. Emery indicates they can be more easily propagated by winter cuttings placed in a propagation bench supplied with intermittent mist and bottom heat. If you do try to propagate this species or especially if you buy potted ones, remember to treat their roots with extreme caution. Plant the root ball with little or better NO disturbance.

by Dirk Walters, illustrations by Bonnie Walters | Dirk and Bonnie Walters are long-time CNPS-SLO members, contributors, and board/committee participants. In addition to his work at Cal Poly, Dirk is the current CNPS-SLO Historian.

Silene laciniata

Coastal catchfly

Late summer or early fall (or more appropriately “late dry season”) is a downtime in our local wilds, especially true when we’ve had no significant rain after December. Even the animals seem to be resting. But if one looks carefully in our coastal dune scrub, one may just see a FEW bright red flowers commonly called Indian Pink around here. Indian Pink is also the name in RF Hoover’s book Vascular Plants of San Luis Obispo County. I found a better common name on the internet, Cardinal Catchfly. Either way it’s Silene laciniata.

Since it has very weak stems, Silene laciniata has the habit of using other plants for support. Look for it growing out of the canopies of relatively short plants. Our chapter area is near the northern extent of this species range; it can be found on our coastal dunes and further inland on serpentine outcrops. Its usually hidden, paired leaves are broadly joined at their bases and appear, at first glance, to be quite grass-like. But no grass has opposite leaves and a close examination of the leaf blades will show a single, larger midrib.

Coastal catchfly (Silene laciniata)

Coastal catchfly (Silene laciniata)

An examination of Bonnie’s drawing shows what appear to be the five fused petals at the end of a long tube. The tube is formed by the fused sepals (calyx). The petals are actually separate. If one were to slit down the side of the calyx tube, the five separate petals would simply fall away from each other.

Each petal consists of two quite distinct regions. The showy part is bright red and is called by botanists “the blade.” Each thin basal portion, called “the claw” by botanists, is the length of the tube and basally attaches separately to the receptacle below the ovary. The sepals and stamens also attach to the receptacle. So, in spite of casual appearance, the ovary is superior.

The local common name, Indian Pink, I believe to be the less desirable today because of the use of “Indian.” The name, Indian, often indicates that the plant in question was used in some way by the native North American peoples. I didn’t find any reference to their use of this species either on line or in my library. I’m guessing that the use of the word, “Indian,” here simply refers to it being native to California.

The second name, Pink, refers to a common trait in its family, Caryophyllaceae, or pink family. Pink, in this case, does not refer to the flower’s color, which is bright red, but to the fringed petals. That is, it refers to the tailors’ practice of cutting the edge of unsewn fabric with pinking shears to leave it toothed to prevent it from unraveling. Now Cardinal Catchfly is a much better name.

First, the flowers are bright red like the plumage of a cardinal. The term, catchfly, refers to a common trait found in many flowers that produce many special trichomes (hairs) on their sepals. These individual trichomes resemble the colored pins often used to stick into maps; they have short shafts and large round heads. When mature, these “heads” break down into an acrid, terrible tasting glob that is sticky enough to ensnare small insects such as flies and bees.

Why would this be an advantage to the flower? Many flower visiting insects, when prevented from entering the flower the correct way will attempt to steal nectar by biting a hole through the base of the flower or calyx. This is pure thievery as the insect gets the costly nectar without pollinating the flower.

How might a Cardinal Catchfly be pollinated? First thing we need to do is note that the only possible (legal) entrance to the deep, relatively narrow floral tube (where the nectar is produced at its base) is via a very tiny hole through which the style and stamen filaments emerge. So a pollinator would have to be either small enough to enter the hole (not likely) or have a very long, thin proboscis or tongue. That eliminates essentially all flies, bees and beetles, which have short chewing mouth parts.

That leaves three common long-proboscis pollinators – butterflies, moths and hummingbirds. Butterflies usually require flowers that provide a landing platform. The Cardinal Catchfly is orientated so that the showy parts (blades) of the petals are vertical, which does not provide a landing platform for butterflies. Cardinal Catchfly blooms during the day so that should eliminate most moths.

Further, I haven’t noticed any pronounced floral odors produced by this flower. A day-flying pollinator that hovers in front of the flower, possesses a long, thin beak (and tongue), and with keen eyesight in the red portion of the spectrum would be a humming bird. In addition, birds tend to have little sense of smell. It’s a conclusion that could have been gotten easily from the internet, but not nearly as fun.

by Dirk Walters, illustrations by Bonnie Walters | Dirk and Bonnie Walters are long-time CNPS-SLO members, contributors, and board/committee participants. In addition to his work at Cal Poly, Dirk is the current CNPS-SLO Historian.

Calystegia macrostegia

Coastal Morning Glory (California)

The plant featured on the June 2013 cover of the Obispoensis was chosen because of a request. It is the California, coast, island, or wild morning glory (Calystegia macrostegia).

The common name, false bindweed, is sometimes used instead of morning glory. Bind weed and morning glory are often used interchangeably. This species was chosen because of a request by CNPS member Yolanda Waddell who asked some time ago about the plant. Bonnie and I encourage anyone to email, write, or even call us with comments or questions about the drawings or articles or both. After doing this since the mid 1970’s, we especially like to receive suggestions for native plants that others might find interesting.

Plants called morning glories generally produce large flowers with five fused petals arranged in the shape of funnel. Bindweeds generally have smaller flowers. The morning glory common name refers to the fact that individual flowers tend to open in the morning and close by the same afternoon. Most of the time the flowers are basically white, but they may have pale pink veins. As the flowers age, they may take on a pinkish tinge.

There are at least two possible explanations for color changes in flowers. First is that it is caused merely by the aging and dying of the petal’s cells and has no survival value. However, there is a second possible explanation. It has been documented that some flower color change is controlled by the flower in order to signal its pollinator that this flower has been visited already so don’t waste your time visiting me.

Why would a plant do this? If pollinators visit only unpollinated flowers, then the pollinators will visit more flowers because they will visit only those flowers still requiring a pollinating visit. Is the color change in morning glory ecologically significant? I don’t actually know, but it would be interesting to find out.

Let’s look at Bonnie’s drawing. It shows a single twining stem. Note how thin the stem is drawn; it’s less than oneeighth inch in diameter. From each leaf bud a stalked 1-3 inch flower or pair of flowers arises. This means they are widely spaced along the individual stem. But, in the field, morning glory stems are rarely found single. A given rootstock produces many stems that will start out growing side by side, and because they twine they wrap around each other forming a structure similar to a braided rope. Since each individual stem is producing flowers, a given length of “rope” produces many flowers that appear to be growing side by side.

Not only that, morning glory plants may cover large areas. When this happens, the “ropes” criss-cross to form a net. The flowers then appear be arising from a mat. Because of this, most photos are distant shots of the mat and therefore don’t show the details of the stem. Some books indicate that the stems of this species of morning glory are somewhat woody at the base. To be truthful, I’ve never looked for this because one is totally overwhelmed by the mat of herbaceous “ropes.”

Leaves in this morning glory are extremely variable in size. On new stems leaves may be only an inch or so long but at other times they can grow to be nearly six inches long. Leaves are triangular with two prominent lobes at the base.

Calystegia macrostegia is an extremely variable species. The most recent Jepson Manual recognizes six subspecies throughout its range which runs mostly along the coast from just north of the Bay Area to just south of the Mexican border. There are also subspecies on the Channel Islands. Therefore this morning glory is almost an endemic Californian, i.e., restricted to the state. The subspecies to be expected in our area would be C. m. ssp. cyclostegia. Since this subspecies is found almost exclusively on the mainland, I think the best common name for it would be California morning glory or even better California coastal morning glory.

There are three genera that typically bear the morning glory common name. They are Calystegia, Convolvulus, and Ipomoea. Ipomoea is native to the old world and is the genus of garden morning glories. In older plant ID books, species now separated into Calystegia and Convolvulus were all included the genus Convolvulus. Currently these two genera are separated most easily on the size and location of two bracts that are attached to the flower stalk.

In Calystegia, the bracts are large and totally hide the calyx. [Caly = calyx or sepals and stegia = Greek meaning to hide]. Macrostegia refers to the fact that the hiding bracts are large (macro).

In Convolvulus, the tiny scale-like bracts arise from near the middle of the flower stalk.

by Dirk Walters, illustrations by Bonnie Walters | Dirk and Bonnie Walters are long-time CNPS-SLO members, contributors, and board/committee participants. In addition to his work at Cal Poly, Dirk is the current CNPS-SLO Historian.
Fremontodendron californicum

Fremontodendron californicum

Flannel Bush

This month’s cover drawing by Bonnie Walters is a repeat of flannel bush, Fremontodendron californicum. It was last used on the Obispoensis cover back in 1991. Does anybody remember it?

Fremontodendron classification

It is being reused now due to a request Bonnie received to use some of her drawings for a project associated with “Learning among the Oaks” program. Of course, this required us to go back into our archives to find it. Also, it was obvious to us that the write-up that accompanied the earlier cover was clearly out of date. Back then the article stated that flannel bush was “a member of the moderately large (65 general and 1000 species) and predominantly tropical family, Sterculiaceae. The most famous member of this family by far is cacao, Theobroma cacao, the plant from which from which chocolate is made.”

Today we have to accept the conclusion that flannel bushes are part of the large (266 genera & 4025 species), cosmopolitan (but still favoring warmer regions of the earth) Malvaceae. This family is most often called the cotton, hibiscus or mallow, and obviously chocolate family. The most obvious characteristic shared by flannel bush and the rest of the Malvaceae is the fusion of their stamen filaments into a tube that completely surrounds and thus hides the ovary and style base. One other note, the beautiful yellow perianth elements found on flannel bushes are sepals not petals; Fremontodendron does not have petals. This is because there is only one whorl of perianth and when that happens, botanists almost always define them as sepals.

Back in 1991, it was noted that Fremontodendron in California had only two species – F. mexicanum and F. californicum. In 2013 we have to acknowledge that there are now three recognized species. A new species with a very restricted range (found only in Yuba & Nevada Counties) has been separated from F. californicum. This new species is F. decumbens or the Pine Hill flannel bush.

Growth Habit

Unlike the other species which are erect, small trees or large shrubs, Pine Hill flannel bush grows flat on the ground. The new Jepson Manual indicates that this species is “morphologically, genetically” distinct (i.e. looks different and doesn’t cross with) from the other species.

Use in the Garden

As one might guess because of its large flowers, flannel bushes ought to be sought after as horticultural plants. The problem is that they are considered hard to grow. They require well drained soils with little summer water. If one tries to plant them in clay, such as found around San Luis Obispo, one internet reference recommended digging a large hole (three feet across and deep) and filling it with sand before planting. This will keep the soil in contact with the root crown from prolonged contact with moist soil. Summer watering (after establishment) and/or moist soil in contact with the root crown will kill it in a couple of years.

The pure species in cultivation is mostly F. mexicanum as it has the largest flowers. However, this species is restricted to extreme Southern California and adjacent Mexico. Because of this, gardeners have created hybrids and selections that combine the environmental latitude of F. californicum with the large flowers of F. mexicanum, thus making the hybrids much more garden friendly.

Gardeners on the internet stress that flannel bushes are large plants and don’t fit well into small suburban settings. They also noted that the pubescence (hairs) that shed from the twigs can be very irritating. Therefore, it might be best to plant it where people do not congregate.

Fremontodendron in the Wild

F. californica is found in desert washes and on dry, well drained foothill slopes. It is particularly common in the high desert and southern Sierra foothills where it prefers locations soil surfaces are habitually dry yet have available water from relatively shallow water tables. This is because their root crowns are particularly susceptible to various pathogenic fungi that live near the surface. It is these soil pathogens that make it difficult to maintain in cultivation.

Viewing Flannel Bush in SLO County

It can be found in our county in scattered colonies along the crest of the Santa Lucia Mountains and on a few of the higher peaks in the interior. The most accessible stand is just east of the forest service road to the Sergeant Cypress Grove on West Cuesta Ridge. Most of our plants have smaller, three-lobed leaves instead of the more common five-lobed leaves characteristic of the species. Because of this Dr. Robert Hoover named our local plants, F. californicum var. obispoense. I also think I remember Dr. Robert Rodin, a plant anatomist and morphologist, telling me that the flannel bushes on West Cuesta Ridge also had one less chromosome than the rest of the species. If this is true, it would further strengthen the separation of our plants into a distinct variety.

A Local Hybrid

I have one last note. A member of our chapter enters the story of producing a much more water-tolerant Fremontodendron garden. This cross, between Fremontodendron californicum and the tropical monkey’s hand tree (or Chiranthodendron pentadactylon) was being propagated for eventual release into the trade at Rancho Santa Ana by then Rancho graduate student and later SLO County Chapter member Austin Griffiths. At least one of these inter generic hybrid plants was planted on the Cal Poly campus. I do not know if it is still living there.

by Dirk Walters, illustrations by Bonnie Walters | Dirk and Bonnie Walters are long-time CNPS-SLO members, contributors, and board/committee participants. In addition to his work at Cal Poly, Dirk is the current CNPS-SLO Historian.
Asparagus asparagoides

Asparagus asparagoides

Asparagus Fern or Bridal Creeper

This month’s plant is a South Africa native that has become naturalized in Southern California where there has the potential to become an extremely troubling weed species. It is already considered so in some localities in Southern California, New Zealand and Australia. It had become a major infestation in the oak grove near Lupine Point in the Los Osos Elfin Forest until it was successfully removed after much effort.

The problem with its eradication is obvious from looking at the cluster of corms that form just under ground. If left to multiply, this corm mat forms an extensive, impenetrable mat just below the soil surface that prevents other plant roots from getting to the nutrients they require. A second problem with the corm cluster is that if one just goes out and attempts to pull them up or cut them down, the corms just send up new shoots. One would have to repeat the removal process until the corms have been starved to death. That would be a long arduous process.

The fast and extensive stem and leaf growth is also a problem. It allows the asparagus fern to cover existing plants so well that sunlight can’t get to them.

I asked Bonnie to draw the plant with flower buds only because plants currently available to us are at that stage. I suspect that, if deadlines weren’t a consideration, a plant with fully open flowers might have been found since its blooming period is from December through April. But more importantly, this species’ vegetative state is so distinctive that the smallish, nondescript flowers are often overlooked anyway.

A word of warning, written descriptions of this plant in many books are totally deceptive. First, what looks like leaves are in fact flattened stems, which botanists often term cladodes. Unfortunately I also ran across several other technical terms for them.

How does one know they are “flattened stems” and not what they actually look like – “leaves.” All vascular plants have the same leaf-stem morphology. First the stem is divided into alternating nodes where the leaves are attached and internodes where there are no leaves. The exterior nodal structure includes the leaf and a bud found in the upper angle between the leaf base and the stem. When the bud germinates it produces a new stem which then can produce more leaves. This means that a given portion of stem produces a leaf only once or leaves are produced only during the first year of that particular stem’s life.

Remember, buds produce new stems only. So a reexamination of Bonnie’s drawing shows the green flattened stems (cladodes) arising from the angle of a small grayish scale. That scale is all there is to the true leaf. Using flattened stems for leaves is considered an adaptation to drought conditions.

As an example of how confusing this can be, look at the identification keys in the New Jepson Manual. The keys from group to family to genus to species all assume that you know that the leaves are those tiny, insignificant, hardly visible scales under the things that everyone but a botanists would assume where leaves but aren’t.

Bonnie has drawn a couple of flower buds coming from the axil of leaf whose bud grew into the cladode. Examine the node again very carefully. You will note that there are actually three scales visible. The largest one is the leaf and the two smaller ones just visible are the bracts (leaves associated with flowers) whose buds germinated to produce the flowers. Botanists consider flowers to be highly modified leafy branches. Why they think this must be the subject for another time. Oh yes, that means this plant must produce 3 leaves and buds per node. Two of them only develop when that node produces flowers, otherwise they would be invisible.

The plant has a number of common names as might be expected of a plant used by humans. Its primary use is in floral arranging. Its thin stem and abundant dark green cladodes together give it a kind of filmy or ferny appearance which explains the “asparagus fern” name.

Its long use in bridal bouquets explains its African bridal creeper, bridal-veil creeper, or merely bridal creeper names. Other names that I’ve seen include Gnarboola, Smilax or Smilax asparagus. The last two names should be forgotten as they indicate it is related to the genus, Smilax, which it is not. I assume Gnarboola is its name in its native Southern Africa. The genus, Asparagus, belongs to a group of monocots that produce flowers with a perianth of six sterile elements that are more commonly called sepals and petals.

This genus’ flowers have 3 greenish-white sepals and 3 identical greenish white petals. When sepals and petals are identical except for position (sepals are always the outer whorl and petals interior to the sepals) botanists use the term “tepals.” There is a large assembly of tepal plants including the lilies, amaryllis, tulips, onions, and garden asparagus. The list could go on and on. The problem with this group is that all their flowers are built on the same plan and whenever this happens taxonomist often can’t agree on family or even ordinal boundaries. For example, a search on my library and internet finds this genus placed in the lily family (Liliaceae – order Liliales) or the Asparagus family (Asparagaceae – Asparagales). Added to this the current distinction between these orders has to do with different DNA sequences and unique chemical constituents found in their seed coats, neither of which are hardly field characters. For the record, the new Jepson Manual puts this plant in the Asparagales and the Asparagaceae.

by Dirk Walters, illustrations by Bonnie Walters | Dirk and Bonnie Walters are long-time CNPS-SLO members, contributors, and board/committee participants. In addition to his work at Cal Poly, Dirk is the current CNPS-SLO Historian.
Amanita phalloides

Amanita phalloides

Why is the Death Cap mushroom so deadly?

On New Year’s Day I visited a favorite, and normally productive, chanterelle patch outside San Luis Obispo to discover an enormous fruiting of the dangerously toxic death cap mushroom (Amanita phalloides).

My culinary disappointment was tempered by my growing fascination with the question, “Why are mushrooms deadly poisonous?” Proximally, the answer is direct: because they contain a peptide, alpha-amanitin, which halts RNA transcription in the cell nucleus. In broader context, the question should be rephrased, “What ecological advantage and evolutionary fitness does the presence of this toxin contribute?”

Amanita phalloides is a newcomer to California. It is known to be a native of Europe, and its first verified collection in California dates to 1938. Anecdotally, its introduction is ascribed to an accidental arrival on the roots of cork oak trees. It is now known from Southern California to British Columbia. A similar introduction (on the roots of Italian chestnuts?) affects the East Coast.

Death cap is an ectomycorrhizal symbiont. This means it forms connections on the root-tips of forest trees; in California, its typical (but not exclusive) partner is coast live oak. Unlike many symbionts which are highly host specific, death cap is promiscuous in its associations as it spreads worldwide. It is now present in South Africa, Australia and most other similar climes.

Ectomycorrhizal (EC) fungi collect major nutrients, nitrogen and phosphorous, and exchange these with the host tree for sugars. Delicate hyphal strands extend outward from the root tip mass into the surrounding soil and mulch. EC also allows efficient active transfer of macronutrients, micronutrients, and soil water to the tree. The chronic phosphorous limitation in serpentine soils makes the EC symbiosis especially important for local forest types on this soil. Studies in Norway discovered up to 50% of a birch tree’s sugar is exchanged at the root tips with EC symbionts.

Death Cap - Amanita phalloides

Death Cap – Amanita phalloides

Other studies describe how a mushroom, Laccaria bicolor, lures springtail insects (Folsoma candida) into traps, consumes them, and transfers the nitrogen obtained to its host tree.

Trees form non-exclusive associations with many fungi. Studies at Pt. Reyes show more than 15 taxa of EC fungi present at the root tips of coast live oak from a single grove. Most of the live oak symbionts are not deadly or even dangerous, and include the sought after chanterelles.

It is an entirely open research question as to whether the recent invasion of Amanita phalloides into the California oak forest is supplanting native fungi. Studies (in Bishop pine) have shown that EC fungi partition their habitat niches very precisely, allowing multiple fungi to coexist in close proximity. I have visited the particular chanterelle patch since the 1970’s without noticing the Aman5.0ita, so the 2012 fruiting might possibly represent a replacement of one symbiont for another, or just be a fortuitous fruiting of an established co-dominant.

The “competitive exclusion principle” argues that if these organisms are competing within the same precise niche, the most successful will replace all others. The deadly toxin of Amanita’s is alpha-amanitin. This is a heat-stable cyclic peptide that interferes with the transcription function of RNA in the nucleus of cells of virtually all organisms.

Humans, dogs, rabbits, and guinea pigs are equally poisoned. The toxic crisis is caused by irreversible liver or kidney damage, as the molecule concentrates in those organs. More expansively: organisms other than bacteria are affected by alpha-amanitin. Insects, worms, flowering plants, and even viroids (infectious single strands of RNA) that cause “mad cow” and disease in plants cannot replicate when treated with amanitin.

Amanitin is a large, very stable molecule (C39H54N10O14S) so it represents a significant metabolic cost to the fungus to create. Several, widely unrelated, taxa of gilled mushrooms possess amanitin toxin, so its synthesis has been separately evolved several times in fungi –supporting the assumption this represents an important competitive innovation for the species. Fortunately, amanitin is too large to cross the blood/brain barrier, so even victims with irreversible liver and kidney damage due to mushroom poisoning are not affected mentally.

An evolutionary entomologist working in New York State, John Jaenike, has discovered four species of mushroom flies in the genus Drosophila that lay eggs in the gills of fruiting Amanita phalloides. The fruit fly taxa are related to ones that inhabit rotting skunk cabbage, but in New England have recently transferred to the recently introduced Amanita fruitings.

Jaenike discovered that Amanita phalloides is toxic to the damaging parasitic nematodes Howardula that reproduce in the stomach of fruit flies. The toxicity of the death cap to the parasitic nematodes results in much greater egglaying (fecundity) by the fruit flies. The fruit flies are affected by the toxic amanitin, especially the males, but the poison is more than offset by the increase in reproduction.

Janike also discovered that most other insects using mushrooms as egg laying sites (craneflies and forest gnats) shun use of the Amanita (due to its toxicity).

Fruiting mushrooms are a scarce and erratically scattered resource for reproduction and larval feeding. Fruiting mushrooms are fully and completely consumed by mushroom gnat larvae, and Jaenike postulates fierce competition for insect breeding sites. Jaenike has published several papers describing the Amanita-Drosophila-Howardula food web. Mushroom flies secured a niche free of competition by exchanging an evolved tolerance to sub-lethal poisoning for escape from nematode parasitism. The increased fitness leads to greater egg-laying ability, and has provided the evolutionary inertia for this recent adaptation.

Nematodes are significant pests of commercial mushroom production, epidemic infestation can result in the loss of the growing beds. The oyster mushroom, Pleurotus osteraceus, traps and consumes nematodes in noose-like knots of hyphal tissue.

So why are Amanita so poisonous? It is an unlikely deterrence to vertebrate predation of the fruiting caps, as the effect is slow-acting (36-72 hours before the toxic crisis in humans) and the toxin is not concentrated in the cap. Evidence supports the hypothesis that the fitness obtained from synthesizing the toxin is secured within the hyphal network. Perhaps toxic Amanita obtain nitrogen from poisoned nematodes, or protect themselves (and their symbiont hosts) from plant parasitic nematode predation.

Perhaps the toxin suppresses the growth of competing fungal webs. It seems clear the toxic effect of death cap is intrinsic to its invasive success worldwide.

John Chesnut | Rare Plant Coordinator and Education Committee at CNPS-SLO, John teaches horticulture at Cal Poly

Sources:

Jaenike, J., “Parasite Pressure and the Evolution of Amanitin Tolerance in Drosophila,” Evolution,Vol. 39, No. 6 (Nov., 1985), pp. 1295-1301. Jaenike, J. and T J. C. Anderson, “Dynamics of Host-Parasite Interactions: The Drosophila-Howardula System,” Oikos Vol. 64, No. 3 (Sep., 1992), pp. 533-540. http://web.uvic.ca/~stevep/pdfs/AmNat_02.pdf

Pringle, Anne, and Else Vellinga, “Last chance to know? Using literature to explore the biogeography and invasion biology of the death cap mushroom Amanita phalloides.” http://www.msi.harvard.edu/downloads/teacherworkshop/Readings/Ben_Papers%20_TWS/Pringle%20and%20Vellinga%202006.pdf

Pringle, Anne, Rachel I. Adams, Hugh B. Cross, and Thomas D. Bruns, “The ectomycorrhizal fungus Amanita phalloides was introduced and is expanding its range on the west coast of North America,” Molecular Ecology (2009). http://arnarb.harvard.edu/faculty/pringle/pubs/Pringle_MolEcol_2009.pdf

Wolfe, Benjamin E., Franck Richard, Hugh B. Cross, and Anne Pringle, “Distribution and abundance of the introduced ectomycorrhizal fungus Amanita phalloides in North America,” New Phytologist (2009). http://www.oeb.harvard.edu/faculty/pringle/documents/Wolfe_Ap_Distribution.pdf

Wieland, Theodor and H. Faulstich. Amatoxins, Phallotoxins, Phallolysin, and Antamanide: The biologically Active Components of Poisonous Amanita Mushrooms. http://informahealthcare.com/doi/pdf/10.3109/10409237809149870

Horton, Thomas R., and Thomas D. Bruns, “The molecular revolution in ectomycorrhizal ecology: peeking into the black-box,” Molecular Ecology (2001)10, 1855–1871. http://www.cnr.berkeley.edu/brunslab/papers/

Quercus douglasii

Quercus douglasii

Blue Oak

Bonnie’s drawing on this cover of the Obispoensis includes an acorn, a couple of leaves and a two individual blue oak (Quercus douglasii) trees from Shell Creek.

This species of oak is extremely common in a vertical band through the center of our Chapter area. It is most common east of the Santa Lucia crest and west to the San Juan River drainage. It occurs only occasionally near the coast where it is replaced by the coast live oak (Q. agrifolia). In the Carrizo Plain area the Tucker oak (Q. john-tuckeri) replaces it.

Unique coloring

I suspect all of us who know the tree know it as blue oak. Its common name refers to its bluish green deciduous leaves and/or its pale gray bark. Other names I’ve found include iron oak, mountain white oak, or mountain oak. The light blue/gray color is particularly evident when compared to evergreen oaks such as liveoaks (Quercus agrifolia, interior live oak (Q. wislizeni) and gold cup oak (Q. chrysolepsis), all of which live within or near the blue oak range. But remember, both leaves and bark are quite variable in color based on where the tree grows.

Leaves and bark are lighter (i.e., more gray or blue when the tree grows in open groves on sunny south and west facing slopes and darker and greener where moisture is present such as north and east facing slopes).

Blue oaks prefer well drained soils so they tend to be found on foothill slopes surrounding California’s Central Valley. Yes, blue oak is endemic to California, which means that it is found naturally only within the political boundaries of California.

A great deal is known about the ecology of the blue oak. So much that it is difficult to chose what to emphasize in a general piece such as this. When I did a web search of Quercus douglasii a fantastic tell-all forest service website headed the list. The web address of this site is http://www.fs.fed.us/database/feis/plants/tree/quedou/all.html. One thing I will mention about the web site is that the small amount of stuff I knew already I noted was correct. This leads me to conclude that the vast amount of detail I didn’t know is also true.

Ground cover

One item worth mentioning is the ground cover of herbs Bonnie has drawn around the base of the oak trees. The species found in this area within the drip line of the tree’s canopy are quite different in composition and abundance from the species outside the drip line. Several hypotheses have been proposed for this phenomenon. First, the deep roots of the oak bring up nutrients from deep in the soil where they are below the reach of the shallower-rooted herbs. Because the leaves are a “leaky” system, some of the water soluble nutrients get deposited on the surface of the leaves where they are washed off and drop to the soil under the tree. It has also been noted that during the hot parts of the day, cattle seek shade under the trees. While there, they deposit undigested or unabsorbed nutrients under the tree. Either way, it is hypothesized that there is higher nutrient availability under the tree’s canopy than outside it.

Blue Oak and California native ethno-botany

I will make just a quick note on native California peoples use of the blue oak acorns. All writers discussing California native ethno-botany acknowledge that acorns of this species and most other oak species were gathered and used. In a list of acorns used by the Native Californians that I found on the internet, blue oak tops the list. Essentially all references refer to it as producing the “sweetest” acorn. I assume that means it has the best flavor, which should mean it has the lowest tannin content. Tannins are complex chemicals that are not only bitter tasting, but also interfere with digestion by creating blockages in the digestive tract.

Since tannins are water soluble, they are removed by leaching. Native Californians usually leached acorn meal by placing it in a basket and then placing the basket in running water. I’ve heard people ask where they found the water for all the required leaching. Today, if one wants to eat acorns, one must use treated tap water. That would prove to be quite expensive. One must remember that pre-European Native California populations were relatively small and scattered. There was no Mexican- or European-style field agriculture (except within the Colorado River Valley) in California.

There was habitat manipulation as was discussed by our recent banquet speaker, Kat Anderson, but the smaller population and low impact vegetation manipulation would mean that most streams would flow longer into the dry season and be less polluted than we no find them today. They could simply have been able to put their acorn meal filled baskets into any nearby water course with no ill effect.

by Dirk Walters, illustrations by Bonnie Walters | Dirk and Bonnie Walters are long-time CNPS-SLO members, contributors, and board/committee participants. In addition to his work at Cal Poly, Dirk is the current CNPS-SLO Historian.
Polypodium californicum

Polypodium californicum

Common Polypody or California Polypody

Bonnie’s drawing this time represents a fern recently found in the Los Osos Elfin Forest. The fern is the common or California polypody (Polypodium californicum). It was found by Al Normadin while scouting for his recently led trip in the Elfin Forest. It is a quite common and widespread fern on the Central Coast, where it is commonly found growing along edges or out of cracks in rocks. It is especially common on north facing slopes.

However, I was surprised to find it reported from the Elfin Forest. This is because ferns generally require consistently available soil moisture. Since the Elfin Forest Reserve’s sandy soils tend to lose their moisture and it doesn’t rain for over six months, one would not expect to find many fern species here. I suspect these particular ferns are able to do so because they occur in shade near or under the pygmy oak over-story where the oaks provide shade and extra moisture. The extra moisture comes from the ability of the pygmy oaks to condense water on their leaves and twigs from the common coastal fogs. This fog drip can add over 20 inches of extra water to that which falls from the clouds.

Even the extra moisture from fog drip might not be enough to support California polypody were it not for this particular fern‘s ability to go into an extended period of dormancy. That is, the living green leaves simply die back to the under ground stem (rhizome) and decompose during the dry months. Therefore this fern actually totally disappears from view during the rainless months of the year.

This disappearance probably explains how it could be present, yet not recorded in a species list. Then when moisture returns to the soil, the buds on the rhizome produce one to several new leaves. A note about all of our native ferns, the only visible vegetative structures one can observe without digging are the leaves. Stems and roots are all below ground. California polypody appears quickly after the first rains of autumn.

Bonnie’s main drawing actually shows two non-seed producing plants. The larger one, as stated above, is the common or California polypody or Polypodium californicum. The smaller, but more numerous is some kind of moss. I have no idea what kind. Mosses and their closely related liverworts and hornworts are usually neglected in nature books.

Neither mosses nor ferns produce seeds. Seeds are complex multi-cellular reproductive structures that consist of at least three parts. These include the outer, protective seed coat whose cells contain DNA that is identical to the mother plant, a food supply (endosperm) often consisting of cells controlled by 2/3 mother and 1/3 father DNA, and an embryo whose DNA is one-half from each parent.

Seeds allow land plants to disperse over a land environment. Mosses and ferns do not produce seeds, yet they too are land plants. So by what devise do they disperse over land? They use spores.

Spores are simple, unicellular structures that are enclosed in a thick wall. Like seeds, spores usually are capable of a period of dormancy before they can germinate and grow. In the true plants (Kingdom Plantae, which includes mosses, ferns and seed plants) all spores contain a single set of chromosomes (haploid). In all true plants, spores are always produced in a capsule-like structure called a sporangium, each of whose cells contains two sets of chromosomes (diploid). Since the cells of the sporangium are diploid and the spores produced inside are haploid, something special must happen to at least some of the cells inside the sporangium. This special type of cell division occuring when a single diploid cell (spore mother cells) divides its chromosome number in half producing four haploid spores is meiosis. All sexual organisms do this process some time in their life cycle.

The stalked sporangia in common polypody are produced in clusters on the underside of leaves. These clusters are termed sori (plural) or sorus (singular). Bonnie has drawn a portion of the underside of a leaf lobe showing several sori. A typical, single, tiny, stalked fern open sporangium is also shown.

When these haploid spores germinate, they do not produce the fern plant one sees growing in nature. They produce a tiny, barely visible to the naked eye, haploid plant known as a gametophyte. This little plant, (not shown) produces the sex organs that produce either the sperm or the eggs. These gametophytes live on the soil surface where periodically there is moisture enough to create a film of water over soil and plants. The sperm then swims through this film of water to the egg. The fertilized egg grows into the typical visible fern plant that Bonnie has drawn.

Each cluster (sorus) contains a few score of sporangia. Let’s say 60 sporangia. Each sporangium produces approximately 60 spores so a single sorus would be expected to produce 60 x 60 = 3,600 spores. Each leave produces about 20 sori, so the number of spores produced per leaf would be 72,000. Each individual fern plant produces at least 10 leaves so the number of spores per plant is now 720,000. But the California polypody is a perennial and it produces spores almost every wet year of its life. If we are conservative and say a given fern individual encounters only five wet years during it life, then during that individual’s five-year life, it will produce 3,600,000 spores.

How many of these spores must be successful in order to produce a stable population of fern plants? The answer is only two! What happens to the individuals that could have been produced from the other 3,599,998 spores? They die. If 3 or more are successful, the ferns population increases, if only one or none then the fern population decreases.

by Dirk Walters, illustrations by Bonnie Walters | Dirk and Bonnie Walters are long-time CNPS-SLO members, contributors, and board/committee participants. In addition to his work at Cal Poly, Dirk is the current CNPS-SLO Historian.