Nature at UCSB Series: Discovering the Lemonade Berry

Illustration by Diane Kim

Kai Labson

Contributing Writer

Along Lagoon Road at the eastern edge of campus, just over the cliffside fence, is a cluster of a particular shrubby bush: the lemonade berry. With its flat, waxy leaves and small reddish-gray berry clusters, this indigenous plant, known as Rhus integrifolia, is a common sight to UC Santa Barbara (UCSB) beachgoers. However, they may not be aware of the berry’s tart, lemonade-like taste and the plant’s importance in holding the beachside cliffs together.

Common and native to only Southern California chaparral and coastal sage scrub biomes, the lemonade berry flourishes in areas below 900 meters, particularly in canyons and around coastal areas. Although this plant can grow upright up to heights of up to 30 feet tall on mountainous slopes, the plants that we have on campus tend to be flatter and sprawling. Instead, near coasts, this evergreen shrub grows differently in response to sandy soil. 

With relatively small and thick leaves, the lemonade berry is adapted to drought and can easily tolerate full sunlight all day. The berry is small, red, tart, and sticky, similar in size to a pomegranate seed, and grows in clusters at the end of branches. Each seed comes from one flower, which is whitish-pink and appears from December to May. 

While this species doesn’t have anything to do with lemonade, it is indeed edible and delicious — but with a catch. The sour juice can be sucked, but the actual pulp of the berry upsets the stomachs of those who eat it. The scientific name of the plant, Rhus integrifolia, illustrates its familial relation to Pacific poison oak, formerly known as Rhus diversiloba. Like its cousin, contact with the oils of the sweetly-named lemonade berry can lead to skin irritation and itchiness, so care should be taken when collecting any berries.

Native peoples indigenous to California, such as the Ivilyuqaletaam (Cahuilla) and the Kumeyaay, incorporated the lemonade berry into their diet, using it for a variety of purposes. Along with eating the fruits raw, they made a beverage by soaking the berries in water, and ground dried berries into a flour. Additionally, the seeds could also be brewed as tea or ground into water for a medicinal drink that was said to help with fevers.

Another important role that this plant plays is erosion reduction. The beach cliffsides that it inhabits at UCSB are crumbling; often, rocks that were recently part of the cliff face can be heard tumbling down by beachgoers down below. Rhus integrifolia’s affinity for coastal areas, its extensive root system, and its sprawling growth makes it an excellent tool for holding hillsides together and slowing further decay caused by both landscapers and mother nature. 

While iceplant is a more recognizable cliffside plant on campus and throughout California that serves a similar stabilizing role, it is non-native and strangles local wildlife. Native lemonade berry plants not only prevent erosion, but also provide a valuable food source for small mammals and birds such as the bushtit. Thus, planting the lemonade berry bush is the better choice out of the two. 

The lemonade berry grows delicious fruit on its branches while serving important roles in its local ecosystems. The next time you notice this plant on campus, make sure that you appreciate what it does for all of us.