Mt. Tamalpais – from the top to the middle.

Date: 4/25/2019

Location: Mt. Tamalpais

Weather: Sunny, some wind

Site Description: The top-half of Mt. Tamalpais presented many different types of habitats. Two of the most abundant habitats included serpentine outcrops, and vast hills with what appeared to be coastal-looking shrubs and scatters of oak-like trees. The serpentine environments had many different lizards and birds overhead. As we learned in class, these habitats are often too toxic for other plants to live on and only serpentine tolerant and endemic plants can utilize the space as habitat. Throughout the hike, we also passed through sections of forest that contained some douglas firs and oak and tanoak trees.

Species we saw:

  • Mystery Species #1: This star-shaped purple flower had a white cup-like receptacle. It’s erect stem and alternate leaves were pubescent. Its leaves skinny and long, and could be classified as elliptic in shape. It was very short and stout, growing on a sunny, grassy hillside. My initial investigations via cal-flora brought be to 5 different families that I kept switching between. Ultimately, I was honed in on the Campanulaceae, as some of the flowers in this family looked similar to this specimen, varying mostly in stem size, pubescence and leaf shape. In the end, I conclude that this is the common bluecup (Githopsis specularioides). It is an annual herb, native to California.

  • Mystery Species #2: Upon first glance, this species immediately reminded me of the yellow violet that we’ve seen before. Using Calflora, I jumped right to the Viola genus, as the jepson e-manual does not have a key to Violaceae section. and keyed in only on the yellow flowers with lengthy leaves low to the ground. I conclude that this plant is the Viola praemorsa. As for a sub-species, I believe it could be linguifolia, I concluded this due to the “irregular tooth” comment on note 23′. Other characteristics of this flower include: fused, yellow petals that for a cup-like shape (rather than a funnel) and flimsy leaves with irregularly toothed margins. It is a perennial herb native to California. Its leaves look mostly basal, but it does have cauline leaves as well. Leaves have pinnate venation, with some reticulate tertiary venation. The inside of its bottom-most petal has black stripes, which may act as a landing pad for pollinators.

  • One of the species we saw out in the field was Western or Cobweb Thistle (Cirsium occidentale), which is a member of the asteraceae family. It is a perennial herb, native to California (a lot of thistles are not native to california and look very similar to native thistles). When in bloom, it has a pink-to-reddish head inflorescence, it looks very similar to the inflorescences. Its leaves are sharply toothed and the entire plant is covered in many hairs which give it a whitish look. These hairs most-likely aid in giving the plant some ability to avoid desiccation during windy/very sunny days on the mountain.

Summary: The mountain top was absolutely beautiful, and contained many species which we have already seen before. It was a great way to begin reviewing for the upcoming field quiz. The Mt. Tam areas has so many different habitats and plants, it’s really mind-boggling to think about living next to such a diverse/rich area. The top of the mountain especially was full of lizards and snakes ready to soak up the intense sunlight. We also saw some birds that were probably surveying the area for prey.


Additional Species:


Family: Hydrangaceae

Western Fence Lizard

Little spring beauty

Family: Monteaceae

Wide-leafed mule ear

Family: Asteraceae

**Blog posts of previous field trips to come next week, my phone broke and I lost all of my pictures :(**


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