Sudden Oak Death (SOD) is a serious exotic disease that is threatening the survival of tanoak and several oak species in California, including coast live oak. Currently SOD is found in 16 coastal counties, from San Luis Obispo to Humboldt counties. SOD spreads from infected California bay laurel leaves to oaks during wet weather. Management options are available but they are only effective if implemented before oaks and tanoaks are infected, so timely detection of the disease on bay laurel is essential! This is where volunteers like you can help can help out and sample suspected bay laurel leaves at this year’s SOD Blitz in SLO County. The purpose of the SOD Blitz is to inform and educate the community about the disease and its effects, get locals involved in detecting the disease, and produce detailed local maps of disease distribution. The maps can then be used to identify those areas where the infestation may be mild enough to justify proactive management.
The SOD Blitz begins with a training session/presentation where information on the disease and its symptoms on both oaks and California bays are presented, as well as how to collect and record samples of bay leaves. Volunteers then collect suspected bay leaves as well as information about trees and locations over the week-end. Collecting is done individually or in groups, and you can collect as many or few samples as you have time available before dropping off samples at the collection locations by noon Monday. All collecting materials will be handed out at the trainings. Suggested survey and collection locations will also be posted at the trainings, although you are welcome to identify your own property or area of interest. The collected samples are placed in bins at designated collections spots by Monday before noon so they can be sent to the Berkeley Lab for processing.
This year, we will expect to have at least 2 free training sessions, one in North County and one in San Luis Obispo, and all materials needed for collecting will be provided.
The 2017 SOD BLITZ
- Thursday May 11 from 1-4 pm at SLO County Department of Agriculture, 2156 Sierra Way, San Luis Obispo, CA (limited to 50 participants, registration is suggested but walk-in are welcome as long as space is available). Those of you that have collected past and want to collect in your areas in 2017, please let us know before the Blitz and we provide an updated map.
- Friday May 12, 6pm to 8pm, SLO County Atascadero Library, Martin Polin Community Room, 6555 Capistrano Ave, Atascadero, CA.
Collecting will take place on Saturday and Sunday, May 13 and 14.
Register for Training: http://ucanr.edu/2017sodblitztraining Additional information will be posted on this website and we will include a reminder in the May newsletter. Contact Lauren for additional information firstname.lastname@example.org, 805-460-6329.
Identifying Invasive Oak Pests and Diseases in San Luis Obispo County workshop
FREE Workshop & DPR CEU’s are applied for
April 20, 2017 at the Atascadero Library, 6555 Capistrano Ave, Atascadero
1:00 pm –1:15 pm Check-In
1:15 pm – 1:30 pm Welcome and Introductions, Lauren Brown, California Native Plant Society, San Luis Obispo County
1:30 pm –2:15 pm Goldspotted Oak Borer: Life Cycle, Identification and Management, Speaker: Kevin Turner and Kim Corella, Cal Fire
2:15 pm – 3:00 pm Identification, Impact and Management of Shot Hole Borer, Speaker: Akif Eskalen, University of California, Riverside
3:00 pm – 3:15 pm Break
3:15 pm – 4:00 pm Sudden Oak Death: Identification and Management, Speaker: Kerri Frangioso, University of California, Davis
4:00 pm – 4:30 pm Questions for speakers
The cover drawing and article for this issue of the OBISPOENSIS was written and drawn by Alice Meyer. She was a very active member (and first Hoover Award Recipient in the 1970 and 80’s. She is the one who named our newsletter, OBISPOENSIS, and served as its editor (and typist) for the many years. She is also responsible for setting up the first successful chapter plant sales as well as recruiting our current Plant Sale Chair. She didn’t restrict herself to CNPS. She was also active in the Morro Bay Audubon to which she submitted a number of articles entitled “MEET A NATIVE PLANT’. Below is one of those articles. It was chosen since milkweeds are so important in the conservation of the Monarch butterfly and is being encouraged as a garden plant. Members of this genus serve as the primary food source for Monarch butterfly larva. While eating the milkweed leaves, the larva incorporate the milkweed toxins into their bodies and its these milkweed toxins that protect the Monarch larva from most predators.
I do need to mention a taxonomic update. In her first paragraph Alice places the milkweeds in the taxonomic family, Asclepiadaceae. This was where it was placed up until the 1990’s. Today the two families of milky sapped species [milkweeds (Asclepias) and dogbanes (Apocynum)] have been combined into the single family, Apocynaceae. Milkweeds are primarily temperate in distribution while the dogbane relatives are primarily tropical. Classical taxonomic work always accepted these two families as very closely related. Modern taxonomic studies (including DNA work) have discover the relationships to be intertwined which required their unification into a single family. A number of these formally separated but closely related families have now been combined.
MEET A NATIVE PLANT Asclepias eriocarpus
Milkweed is a perennial plant of the milkweed family (Asclepidiaceae) family. The species shown is common in the Coast Ranges, Sierra Foothills south to Coastal Southern California from 100 to 2000 ft. The species shown is Asclepias eriocarpa (as-KLEP-i-as aor-ee-CARP-a). Monarch butterflies lay their eggs on this plant. The plants are erect and sturdy from 18-36” tall, with leaves 3-4” long, in whorls of 3 or 4 leaves. These are covered with fine hairs, which make them look and feel like flannel. Stems and leaves contain a milky juice, a form of latex.
The clusters of flowers appear in May at the ends of stems between the leaves. The structure of the flowers is very unusual. The corolla is cut into 5 petals. These are turned down so the hide the calyx. The stamens stalks are joined into a tube and the five ‘hoods’ are attached to the base of the column; this is the ‘crown’ of corona, and in this species the crown is pink or purplish. It is actually the nectary of the flower. The flower and its stem is creamy white. In the center of the flower is a fleshy column or tube formed by the stalks of the stamens, capped by the stigma, hiding the two tubes of styles leading down to the ovaries.
The pollen in each anther-cell is a waxy mass of different anthers and adjacent masses of different anthers are attached to a cleft gland. This resembles tiny saddle-bags, clipped together, and if a bee catches her foot in the cleft she may pull out and fly away with two pollen masses to fertilize another flower. To do this, she must get her foot caught in the cleft of another flower.
The probabilities of a bee catching a foot in the cleft of two different flowers, first to collect the pollen sacs, then to deposit them in another flower is so remote that this is called ‘lottery pollination’. When a flower is pollinated its stem enlarges and the petals fall off. The calyx remains at the base of the downy seed pod which becomes 3 to 4” long and the remains of the hoods hang on to the tip of the pod for time. When the pod is ripe, and dry, it splits lengthwise, revealing neat rows of seeds, each with a parachute of fine hairs attached. As soon as the these hairs are dry, the seeds will fly away on the wind to be dispersed. Flowers that have not been pollinated along with their stems, wither and fall away.
-Alice G. Meyer
Spiny emex (Emex spinosa)
Mark Skinner (email@example.com)
Spiny emex is in the Buckwheat family (Polygonaceae) and is an up and coming invasive species in California’s south coast. It’s from the Mediterranean region of Africa infesting disturbed areas especially coastal areas with sandy soils. Spiny emex spreads rapidly, crowding out native species. It has simple lime green or yellowish bronze leaves which looks like dock (which is relative) or spinach. The plant is usually two to twelve inches in diameter and produces seeds with a hard, prickly casing and spines that project from the corners. It is easy to dig out of the ground with a fork. Older plant with lots of seeds can easily shred plastic bags. Handle gingerly with tough gloves. For large monotypic infestations, Telar is an effective herbicide.
This year we were delighted to hear an excellent presentation by Dr. Glen Holstein, Chapter Botanist for the Sacramento Valley Chapter of CNPS. In his talk, Rediscovering and Conserving California’s Prairie Landscapes, Glen spoke of how California’s grassland landscapes in the Central Valley are actually heavily dominated by native wildﬂower species as opposed to perennial grass species. (more…)