San Pedro Valley Park: Trout Farm Trail

Date: 2/21

Location: San Pedro Valley Park – Trout Farm Trail; Northern edge of Santa Cruz mountain range


Site Description: Open trail surrounded by very dense forests. Weather was cold with a lot of moisture in the air. Stream running through beginning of the trail and along parts of the trail due to heavy rain earlier in the week. Dominant species at the beginning of the trail include young California redwoods (Sequoia sempervirens), species from the genus Quercus (oaks), and redosier dogwood (Cornus sericea). Further along the trail, we ran into some manzanitas which dominated a large portion of the top of the trail. Their exact species was undecided, but they shared very similar morphological characteristics, both were believed to belong to Arctostaphylos sp.. Along the trail and deading down the trail, one of the most prominent species that we saw many Eucalyptus trees which I will discuss more later in the blog post.


We departed USF around 1:00pm to avoid rainy conditions. Upon arriving to San Pedro Valley, we parked and met at the beginning of the Trout Farm Trail.

The first species we identified was the redosier dogwood, a member of the family Cornaceae. This shrub had opposite node arrangement with pinnately venated leaves. Dogwoods, in general, are found near water and are often planted outside of houses for aesthetic purposes. The leaves were fairly large with an acuminate apex and a pubescent underside. The most noticeable characteristic about the redosier dogwood was its red stems leading up to the leaves and the white umbel inflorescences. Another cool fact about their leaves was that once ripped apart, the hairs on the underside of the leaves kept the separated leaf parts together.

Continuing on, we saw a very familiar species – the Trillium ovatum. We also saw the giant wakerobin (Trillium chloropetalum [pictured above]), which is related to and looks very similar to the trillium ovatum. The major difference is that it is larger, has petals with a pink-ish tint, and weak mottling on its leaves.

An unfamiliar tree that we ran into was the Coast live oak in the genus Quercus and the family Fagaceae. It had many lichens and mosses living on it and its branches create a canopy-like structure that covered a fairly wide area. Shortly after, we ran into a familiar tree: the Arroyo willow. Its catkins were still fairly active with many male plants having pollen that could be flicked loose.

One flower that we saw during our hike was the greater periwinkle (Vinca major). This bisexual flower has 5 purple petals that are fused at the base; the flower’s shape reminds me of a windmill. The sepals of the periwinkle, which are claw-like and green, are vastly different from their petals. It is an invasive species that usually resides in tropical climates. It belongs to the family Apocynaceae, which are known widely to be tropical flowers. Its leaves have opposite nodes, a somewhat chordate base, and contain a white fluid on the inside that is known as a latex.

Near the top of the trail, we ran into a Manzanita forest where two members of the Ericaceae family dominated the rough soil. They have white bell-shaped flowers that occur in cluster-like inflorescences. The inflorescences pictures are fairly young. Their stems are pubescent, but their brittle leaves with slight dentation are glabrous. Their most recognizable characteristic, aside from their flowers, was their peeling bark to reveal red wood underneath. The specimens pictured are most likely an Arctostaphylus sp..

Eucalyptus trees dominated the entire trail. Aside from the manzanita forest near the top of the trail, eucalyptus trees were found almost everywhere throughout the trail. Originating from Africa, these invasive trees grow very fast when given access to large quantities of water. Their sword-like, sickle-shaped leaves are a unique characteristic to adult eucalyptus trees, while young trees exhibit blue-green stems and more traditionally pinnate-shaped leaves. These trees grow very tall and incidentally provide a lot of shade which limits sunlight for other plants and leaves room for understory adapted plants to grow. On our way back to the cars, along the Brooks Creek Trail, we saw many eucalyptus trees-all of which are believed to be blue-gum eucalyptus (Eucalyptus globulus).

Summary – This trip to San Pedro Valley introduced us to some really cool species, as well as a couple of species that we’ve seen on previous field trips. It was great to get a review through recognizing some Trilium’s, Arroyo willows, Sagebrush, etc.. We also saw some familar familes: Asreraceae, Boraginaceae, Fagaceae, and others. One of the more surprising things to me was how dense this forest was. Most of the sites we’ve been to have been pretty open with mostly shrubs acting as the major ‘canopy’. Additionally, I was surprised to see so many invasive species in the area.

-Additional Species-

Yerba Santa

Golden chinquapin

Beaked hazelnut

California buckeye (and acorn)




Date: 12/14/2019

Location: Batteries to Bluffs Trail in the Presidio, San Francisco CA

Coordinates – 37.796835, -122.479460

Site Description: Coastal cliff habitat with many low shrubs and herbs that overlook the ocean. Next to the trail was a rocky, serpentine outcrop where not a lot was growing. Sub-habitats included streams, cliffs, and dense clusters of shrubs. Dominant species included the non-native ice plant (species unidentified), coyote brush (Baccharis pilularis), and other low shrubs like the lupines and lizard’s tail (Saururus cernuus). Tree cover was rare, but occurred in patches rather than 1-2 trees at a time. The plants in this area must have good adaptions to preventing desiccation, as it tends to be a very windy area around this time of the year.

The weather for our trip was mildly cloudy in the beginning with sparse, light and infrequent rain showers. We departed USF around 1:00pm and arrived in the Presidio at about 1:30pm. Parking the vans on the side of the road, we began at the Batteries to Bluffs Trail in the Presidio. This area was historically a military area, where they once planted many Monterey cypress (Cupressus macrocarpa) trees to bring shade/cover to the area. Most of the trees have since been removed and the Batteries to Bluffs trail, with the help of non profits like Presidio Trust, has somewhat returned to the low-shrub, coastal habitat that it was once believed to be.

One of the first plants that we saw on the trail was the coffee berry (Frangula californica). At first glance, this shrub looked a lot like what would traditionally be known as holly with rich green leaves and small red berries. Similar to holly, coffee berry has dentition on the margins of its leaves, though they appear to be way less extreme. Coffee berry appears in the family Rhamnaceae, within this family flowers often have structures in parts of 5. On the coffee berry, these flowers appear to be a light yellow-ish color. These plants can either grow in the understory of other plants or they can grow out in the open. When grown in the understory, coffee berry tends to have larger leaves to compensate for its placement. If it grows out in the open, it must face the harsh elements that come along with surviving on the coast. As with any coastal plant, this plant faces the threat of desiccation from strong winds. Additionally, sometimes their leaves might appear to be reddish in color-this is because they’re younger leaves that will eventually be predated on by hungry animals. Filling younger leaves with chloroplast comes at a great energetic cost that sometimes does not seem to be beneficial if the leaf is going to get eaten anyway. 

(Left: Yellow lupin; Right: Beach blue lupin)

Continuing along the trail, we saw two species of lupin: Yellow lupin (Lupinus arboreus) and beach blue lupin (Lupinus chamissonis). Although these shrubs looked quite similar from afar, they proved to be different upon closer inspection. Beach blue lupin appeared to be a darker blue-ish green color while the yellow lupin was a more ‘true-green’ color. Both plants had flower-shaped leaves that were palmately compound. These plants fall under the family: Fabaceae. The yellow lupin will give rise to yellow flowers while the beach blue lupin will give rise to purple flowers. Across the Golden Gate Bridge, however, Lupinus arboreus may appear to be purple as well.

One of the more common families that we found throughout the Batteries and Bluffs trail was the Rosaecae family. Flowers from this family sometimes have thorns, but more commonly they have white flowers. Here are some of the species that we observed along the way:

(Pictured below, middle: California Blackberry)

  1. Oso Berry (Oemleria cerasiformis)
  2. California Blackberry (Rubus ursinus)
  3. Coast Strawberry (Fragaria chiloensis)

I haven’t thought much about it before, but it seems that a number of plants in the Rosaceae family are edible. I am excited to learn during the progression of the semester the different families some of my favorite fruits and vegetables belong to.




One tree that we ran into during our hike, which I have mentioned previously, was the Monterey cypress (Cupressus macrocarpa). This tree, that looks very similar to a pine tree, used to be prevalent in the Presidio, however it is not native and halts many other plants from growing due to the large shadow that it casts. It has since been removed in many areas of the Presidio by restoration efforts. This gymnosperm has pressed needle-like leaves against a stem and belongs to the family Cupressaceae. The tree pictures above is a female, as it contains many round cones which Dr. Paul described as looking like a ‘mini-globe’.

Another type of tree that we saw was the arroyo willow (Salix lasiolepis), a diecious and deciduous tree-shrub. This tree is in the family Salicaceae and its bark is responsible for the production of salicylic acid. Its leaves normally appear in alternate positions and are simple, lanceolate leaves with a whitish underside. The leaves have fallen off for now, but will start to come back again after winter is over. The specimen pictured to the left is a male with blooming catkins. These reproductive structures have many anthers on them for spreading pollen, which is most likely distributed by wind to the female trees.


Summary – This trip was a wonderful way to familiarize ourselves with a lot of the shrub-life found in California. I hadn’t realized it until the end, but in many of my other field classes we had seen a lot of the plants that we saw in the Presidio. Coyote bush specifically was one of the ones that dominated the landscapes of the California planes and mountains that we visited. This field trip was a great way to expose ourselves to some new plants and recall some that we found on our Baltimore Canyon trip. I will definitely be returning to this site to study for the field exam.

(Additional Species)

–To be posted later–

Baltimore Canyon Trip

Date: February 7th, 2019

Location: Baltimore Canyon in Kentfield, CA

Time of year: Early spring/late winter

Objective: Observe and identify plant species living in the Baltimore Canyon/Marin County area

Our group departed from USF around 12:00pm, heading North across the Golden Gate Bridge and into Marin County. The weather conditions for the day were cloudy and cold; although it rained earlier that morning, the rain was fairly infrequent and did not persist during our trip. The average temperature throughout the day was somewhere in the 50s. Our drive consisted of many winds and turns as we headed up some residential streets into a public hiking area. After parking our vehicles, we began our trek through the wooded hiking area. Our approximate location is shown in the iPhone screenshot below.


I was too overwhelmed, with being surrounded by what seemed like millions of trees, to record the particular trail we took, but I can imagine that most (if not some) of the plant-life we observed can be found in other parts of the Baltimore Canyon area as well. Along our hike, Professor Paul identified many species and families, none of which we had specifically discussed yet in class but his goal was to give us a general overview of how the rest of our field trips would work. Up to this point, the only relevant thing we had discussed in class was basic plant morphology and identification.

On our way to our descent into the canyon, we identified the following:

Common name: California bay

Family: Lauraceae

Genus+Species: Umbellularia californica

Description: This common bay area plant is a basal dicot with perfect yellow flowers. Their leaves are simple with entire margins. They do produce fruit called bay nuts, which closely resemble avocados. Funny enough, these trees are in the same family as avocados.

Common name: Tanoak

Family: Fagaceae

Genus+Species: Notholithocarpus densiflorus

Description: This plant has really cool leaves that not only have distinctive dentate margins, but they also have dense hairlike structures underneath their leaves that give the leaves their bluish color (thus we would also classify this leaf as pubescent). Many species of oak are currently suffering from sudden oak death. This illness has caused the dying off of many oak plants (which can be seen behind the alive tanoak plant pictures), but luckily oaks are abundant and should not become extinct due to this issue.

Common Name: Big Leafed Maple (fallen leaf)

Description: Big leafed maples are deciduous. Their leaves have palmate venation, and their distinct shape is also seen in the Canadian flag!

Common Name: Scott's Broom

Description: Although this species may look pretty, it is actually highly invasive. It is named Scott's broom because its leaves and stems closely resemble the bristles of a broom.

After observing many different plants, both native and non-native to the Bay area, we headed down into the canyon to take a look at some of the amazing redwood trees (Sequoia sempervirens). Along the way, we spotted a gorgeous way flower called the Western wakerobin (trillium ovatum).

Common Name: Western wakerobin or Western trillium

Family: Melanthiaceae

Genus+Species: Trillium ovatum

Description: This perfect flower is a perennial herb with three leaves, a single stalk, three green sepals, and three petals. As is common with features that occur in threes, this plant is a monocot. It has six long, yellow anthers around the inner whorl and three stigma and an ovary that are positioned in space superior to the male reproductive system. Therefore, this plant has a superior ovary reproductive orientation.

After making our way through the canyon, we began our hike uphill and back to our vans where we headed back to USF around 4:30pm.