Plant Profile: Grindelia (Gum Plant)

Summer in San Francisco is in full swing. While the sun shines and the fog rolls in, there’s no better time to take a walk up on Mt. Sutro and enjoy the native flora. A pretty sight right now is one of our summertime favorites, Grindelia also known as San Francisco Gum Plant. Its bright yellow blossoms look like little daisies and you can see them now up at Rotary Meadow or on the hillside above the Mt. Sutro Native Plant Nursery.

Grindelia (gumweed, gum plant) is a genus of plants native to the Americas belonging to the Asteraceae/Compositae family (commonly known as the aster, daisy or sunflower family). It’s a perennial herb that blooms from July to September. With well over sixty different species, identification can be difficult due to overlapping characteristics and their readiness to hybridize with each other.

There are three species currently growing on Mt. Sutro: Grindelia hirsutula var. maritima (San Francisco Gum Plant), Grindelia hirsutula, andGrindelia stricta. Grindelia hirsutula var. maritima is the rarest of our gumplants, meaning it’s rare throughout its range, endangered in a portion of its range, and endemic to California. The San Francisco Gum Plant grows in sandy or serpentine slopes, and grows to one and one-half feet tall. Other places where this plant can be found are on Twin Peaks, up above the Laguna Honda Reservoir, and in several locations in the Presidio.

The Miwok reportedly made an infusion of pulverized Grindelia leaves and applied it to sores. The Pomo were known to use it as a sedative, antispasmodic, and expectorant. Gum plant was also used to treat poison oak, and even as a tea substitute.

Grindelia species are tough, dependable and fast-growing, long-blooming plants perfect for a drought-tolerant garden. These plants provide cheerful summer color and quality food for pollinators (e.g. bees, butterflies, and birds) when other native plants are dormant. They’re good on hillsides for erosion control, and tolerate sandy, salty, rocky, and clay soils. They’re also deer-resistant.

Come visit Mt. Sutro soon to see these hardy locals and spend a morning or afternoon walking through our lovely trail system. Better yet, join us on any Wednesday morning from 9:30-12:30 at the Sutro Stewards' native plant nursery to help with planting and propagation or to purchase native plants for your garden. See the Nursery page for more information.

References:

1) Grindelia Hirsutula. Wikipedia, June 2016. https://en.wikipedia.org/wiki/Grindelia_hirsutula

2) The Gumplants (Grindelias), Michael Wood; Yerba Buena Chapter of the California Native Plant Society (CNPS); September 1996. http://www.cnps-yerbabuena.org/experience/focus_on_rarities.html?ju...

3) San Francisco Gumplant (Grindelia hirsutula var. maritima). The Presidio of San Francisco website. https://www.nps.gov/prsf/learn/nature/san-francisco-gumplant.htm

4) Grindelia hirsutula var. maritima. California Native Plant Society Rare and Endangered Plant Inventory. February 7, 2012. http://www.rareplants.cnps.org/detail/876.html

5) Great Design Plant: California Grindelia Species for Beneficial Insects. Debbie Ballentine, August 23, 2015; www.houzz.com