The mission of the California Native Plant Society is to increase understanding and appreciation of California’s native plants and to conserve them and their natural habitats through education, science, advocacy, horticulture and land stewardship.

Dedicated to the preservation of California's native plants

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CNPS-SLO Fights for a Better Froom Ranch Specific Plan

CNPS-SLO Fights for a Better Froom Ranch Specific Plan

Beginning in 2015, an LA-based investment group, in partnership with a prominent local landowner and local planning firm, began the process of seeking to develop a large residential project in the City of San Luis Obispo at the corner of Los Osos Valley Road and Calle Joaquin. The project, known as the Froom Ranch Specific Plan (FRSP)

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Welcome to the New Year from our New Chapter President

Welcome to the new year! As your new President, I look forward to an active and fun-filled year working towards our mission of increasing our understanding and appreciation of California’s native plants and to conserve them in their native habitats…

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The Passing of the Presidential Torch

The Passing of the Presidential Torch

Our chapter owes a great deal of gratitude to Bill Waycott for his excellent leadership, and to Diana, his wonderful wife, for her contributions as well. Bill will be staying on the Board as Field Trips Chair, and therefore we will not lose his wisdom. The torch now passes to Melissa Mooney,

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CNPS-SLO “Botanist Development” Workshops in 2020

April 18: Rare Plant Communities in Coastal San Luis Obispo County
May 16: Field Plant Identification in the Field
Fall (Date TBA): Ethnobotany of SLO County

Registration will open about 2 months before each Workshop and will be announced to CNPS-SLO Members via the Newsletter, E-mail and Facebook

2019 Community Award Recipient: ALPS

2019 Community Award Recipient: ALPS

We are pleased to honor the Atascadero Land Preservation Society (ALPS) with our CNPSSLO Community Award. President Mike Orvis and Vice President John Goers accepted the award at our 2020 Banquet.

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Garden weeds

January is by far the best time for weed control in the garden. Nights are cool and the seedling weeds are small and easy to hoe under. Here are a couple of tips for weeding: First, wait two or three days after a rain event to weed, as wet soil is hard to hoe or hand pull weeds from. The soil will fall off pulled weeds easier when the soil is drier; Second, go after the largest weeds first, as these are usually the grasses which set seeds first.

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What do you think about the Obispoensis newsletter going digital only?

Obispoensis is currently available in three formats: Printed and mailed to our members who have not declined, Email, and PDF via the website. 

Newsletter editor David Chipping: 

A lot of chapters are moving to electronic only. and I would like to do the same. Here are reasons for your consideration:
  1) Content is not limited to, or controlled by, page numbering in multiples of 4……any size can be sent;
  2) Color, not B&W;
  3) Obispoensis will be searchable;
  4) It saves trees and energy, and also our costs;
  5) Room for special editions on focused issues with no additional costs or overhead;
  6) People can print their own hard copy if needed.
You would receive an e-mail giving you a link for downloading the latest edition. In the event that a person had absolutely no way to

Download and Print the new CNPS-SLO Planting Guide
thumbnail SLO Planting guide


Try Eating The Weeds

Ethnobotany Notes Great, now you have planted your native plants, and maybe some vegetables. There are also some wonderful edibles that will come up as soon as it rains which you did not...

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Event Calendar

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August 25
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Volunteer at the Hoover Herbarium

Where is the Hoover Herbarium located?

The Hoover Herbarium is located on Cal Poly SLO campus on the 3rd floor of the Fisher Science Building (33) in rooms 352 and 359. Questions: email Jenn Yost at

What do volunteers do?

During the volunteer sessions at the Hoover Herbarium, people can take part in any number of activities.  One of our primary responsibilities is mounting new specimens.  This involves taking dried and pressed plants and glueing them to paper.  When we mount plants, we do it in such a way that those specimens will last for hundreds of years.  Each specimen is a physical record of what plants occurred where and when.  Without this valuable information we wouldn’t know when a species goes extinct, expands or contracts its range, or where species occur.  After mounting, the specimens are databased and geo-referenced.  Then they are filed into the main collection. We have over 80,000 specimens at the Hoover Herbarium.  We are also working on a SLO Voucher Collection, which will contain one representative specimen for each species in the county.  Volunteers look through our specimens and pick the one that should be added to the Voucher Collection.  Additionally, we are actively working on our moss and lichen collections.  Volunteers can choose what aspects of the work they would like to participate in.  Anyone and everyone is welcome. Questions: email Jenn Yost at

What days/hours do you need volunteers?

Hoover Herbarium volunteers sessions are Monday 3-5 pm and Friday 9 – 1. Questions: email Jenn Yost at

Where do I park?

Parking permits are required on campus Monday through Thursday, 7:00 am through 10:00 pm; and Friday, 7:00 am through 5:00 pm. You can either buy a $6 day pass, a $4 3-hr pass, park in a metered space, ride the bus, or park off campus and walk in. Questions: email Jenn Yost at 


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Fiscalini Ranch, January, 2019. Cambria, California. Marlin Harms.

Hypogymnia sp., Tube Lichen. Marlin Harms.

Phaeolus schweinitzii, Dyer’s Polypore.
Marlin Harms.

Mycena purpureofusca, Cone-dwelling Mycena. On cone of Monterey Pine, Pinus radiata. Marlin Harms.

Coastal Lichens on Rock–Caloplaca & Acarospora. 
Marlin Harms

Gymnopilus spectabilis, Laughing Gym, After Showers. Marlin Harms.