Blue and yellow are UC Berkeley colors and a perfect match. But in nature it ain’t necessarily so. The blue here is one of the ceanothus varieties, a native California species. The yellow is acacia, a native of Australia, where it has spread over almost as many acres of the continent as eucalyptus. Park management put this acacia in the ground some years after the ceanothus. Acacia grows very fast and can spread invasively. This makes it ideal for freeway medians and other applications that call for a fast, tough border restrained by pavement. Putting acacia in a park next to native plants was a thoughtless move. This acacia has penned in the ceanothus on both sides and has overarched it. If unchecked, it will drive the ceanothus into the ground and kill it. Similar conflicts can be seen elsewhere between acacia and other native plants.
At the time I took this photo, the ceanothus was buzzing with bees and other bugs that do pollinator duty. (Here’s an example: “Sweet Blue.”) Not a single bug of any kind bothered with the profusion of bright yellow acacia blossoms. Acacia do attract some species of Lycaenidae butterflies (the hairstreaks or gossamer-wings), but these are rarely seen locally, with only one observation in Cesar Chavez Park recorded in iNaturalist, in 2019. Ceanothus, by contrast, attracts a wide range of pollinators. One garden site advises, “A shrub in full bloom is a fascinating mass of bees, hover flies and many more pollinators. Some of our earliest butterflies to emerge also feast on Ceanothus.” Another site lists ceanothus as among the plants that “attract the most variety of pollinators.”
Native plants and the bugs they attract are a vital resource for birds. Most birds, with the singular local exception of the House Finch, feed bugs to their babies for the protein. Seeds alone won’t do it. Native plants mean life for baby birds. In a recent New York Times op-ed, nature writer Margaret Renkl points out that planting just a fraction of each American garden with native plants would mean a massive improvement:
20 million acres of ecosystem that is healthier for other creatures, healthier for human beings, healthier for the planet. With only the smallest effort and expense, we could restore to springtime its most urgent purpose: to bring new life into the world.
What is true for our gardens is true also for our parks. A brave band of native plant gardeners organized as DAWN (Design Associates Working with Nature) seized this truth and acted on it in the early 1980s, planting natives such as this ceanothus and many more on the western slope of the park. Their pioneering work is in danger of being forgotten. We of the Chavez Park Conservancy have worked to raise the profile of the DAWN project and to preserve its achievements. Last year we won a $5,000 grant from the UC Berkeley Chancellor’s Fund for a study of the native plant communities in the Native Plant Area. The Berkeley Parks Department can signal its commitment to native plants by giving the green light for this study to proceed. Here are five recent letters in support. It isn’t complicated. It’s a matter of saving the blue.Letter-of-Support-Cesar-Chavez-Plant-Study-2021-04-06