February 7, 2019
Baltimore Canyon: 37.9369° N, 122.5609° W. 650 ft elevation
On February 7th, our botany class visited Baltimore Canyon open space preserve, which is home to many species, such as redwoods, madrones, and bay trees. We arrived in the afternoon, when the air was crisp and the sun provided some much needed warmth as we made our way along the path. We walked along a paved trail for a good while, frequently stopping to smell the roses (or in our case, the California bay tree leaves). Eventually we began to descend down the canyon to observe the redwood trees. After a while, we finally reached flat land and walked along the creek among the redwood trees and even came across a beautiful waterfall.
While on the paved trail, our class came across Coast silk-tassel, or Garrya elliptica, which we found on the edge of the canyon. Garrya elliptica is a native evergreen shrub belonging to the Garryaceae family and is often found in the coastal zones of California. Coast silk-tassel is dioecious – the tree we observed contained staminate catkins, or inflorescences. These inflorescences are long, pendant, and are yellow-gray in appearance. Meanwhile, the leaves are oppositely arranged and are 2-ranked. The leaves themselves are simple, elliptic, and have revolate margins, rolled downwards towards the undersides to give them a wavy appearance. The apex and base of the leaves are acute-round. Additionally, the leaves have pinnate and reticulate venation.
We later found a Mt. Tamalpais manzanita tree, or Arctostaphylos montana, on the edge of the steep canyon. The Mt. Tam manzanita, which belongs to the Ericaceae family (the same family as the madrone tree), thrives in serpentine soils. The Mt. Tam mazanita is a native evergreen shrub that is endemic to California and grows to only about 0.5 – 2 m. Like the madrone tree, the Mt. Tam mazanita has a smooth bark – however, the bark of the Mt. Tam is darker in color, appearing purple-brown. Its leaves are simple, alternate, and 3-ranked. Its leaves are ovate-elliptical in shape and have obtuse apices and bases. The leaves exhibit primary venation with slightly reticulate venation also observed. The margins of the leaves are entire. Its flowers are white and urn-shaped; they are often surrounded by clusters of apple-shaped fruit (hence, “manzanita”).
Lastly, we discovered a few slinkpods, or Scoliopus bigelovii. Slinkpods are perennial herbs that are part of the Liliaceae family and are native to California. They are commonly found in shady, moist areas and prefer the understory of redwood forests. Slinkpods are monocots that grow from rhizomes. Aboveground, slinkpods often have 2 leaves that grow at the base. Its leaves exhibit parallel venation and are mottled. Slinkpods have an umbel inflorescence – its 3 sepals are flat and pale with purple-brown lining while its 3 petals are dark brown and project upwards. Slinkpods are also perfect flowers – the stamens can be found at the base of the sepals while the style, located at the center of the flower, has 3 branches.
