Mt. Tamalpais (Ridgecrest, CA)

Date: March 14, 2019

Location: Ridgecrest Blvd. on Mt. Tamalpais, CA

Coordinates: 35.633862, -117.679367

Site Description: During this trip we stopped at a few different sites that exhibited very different habitat. While there were areas with hills with low-to-ground species, there were also tall forests with many douglas firs (Pseudotsuga menziesii) and other trees from the family pinaceae. We also stopped by a natural grassland with adjacent serpentine soils. The trees in these areas were more limited to the Quercus genus of the fagaceae family.

*I had to pull images from the internet because my phone broke and I couldn’t recover any of the photos*

Species we saw:


1) Bermuda Buttercup (Oxalis pes-caprae): This native invasive perennial herb is NOT apart of the Ranunculaceae family and is actually apart of the family Oxalidaceae. As an invasive species, its distribution across San Francisco is huge and during the spring it can be seen everywhere. Its flowers are radially symmetrical and it has trifoliate clover-like leaves near the base of the stem. Its four to five petals are fused and form a funnel-like shape. It has bright orange stamens on the insides of its flower funnels. One fun fact about this flower is that its leaves and stem are high vitamin c and taste like sour-apple candy.


2) Ground iris (Iris macrosiphon): This iris, which is common found in the understory and has a gorgeous, showy white flower, is a member of the Iridaceae family. It is a perennial herb native and endemic to California. It has an erect stem bearing a classic iris flower in parts of 3. It has characteristic monocot grass-like leaves with parallel venation. Its stigmas look like extra petals on top of the real petals. The petals themselves are very large and delicate, with many veins running throughout it. The sepals are similar in coloration to the petals, but differ in shape. It has a bold yellow stripe down the middle of it, which I’ve noticed seems to be present in a lot of irises. Its morphological features truly put into perspective how energetically costly this flower must be to make.


3) Cleaver (Galium aparine): As is characteristic of the Rubiaceae family, this family that has leaves that occur in whorls along the length of the stem. The stem and leaves are pubescent, causing the leaf to be sticky to the touch. It’s leaves are oblong with rounded apexes. The whorls occur in 7-8 leaves and it has tiny, white, five-petaled flowers at the terminal end of the stem. This plant is also commonly known as bedstraw because back in the day people used to make mattresses out of it.

Summary: On this trip, we had the chance to see many different ecosystems in the Mt. Tam region. We saw rocky outcrops, oak nulls, tall forests with bare-to-moderate understory, and coastal shrub habitats. In addition to reviewing old species, we ran into quite a few new species in many different habitats. I am always amazed by how much biodiversity California supports.

Other species we saw:

Poison hemlock

Coyote brush

California poppy

Amole/Soap plant

Geraniums sp.

California Barberry

Leave a Reply

Your email address will not be published. Required fields are marked *