Bay Nature magazineSpring 2019

Ask the Naturalist

Why Do Flowers Exist?

March 25, 2019

Why are there flowers? How long have they been around, and where can I see the best spring display in the Bay Area? –Hunter, Sebastopol

Good question, Hunter. Philosophical and religious considerations aside, the primary “purpose” of all organisms, whether they are plants, animals, fungi, bacteria, or viruses, is to grow and reproduce. The number of descendants that remain to carry on the lineage when the parent dies determines success or failure. The bottom line is progeny.

The world was not always such a colorful place as it is now. As long as 245 million years ago, the gymnosperms (plants with exposed seeds, such as ginkgos, cycads, redwoods, pines and their long-extinct relatives) were the dominant plant form, accompanied by mosses, ferns, and liverworts. The landscape was full of various shades of green…and that was about it. Sure, there were interesting dinosaurs and giant insects, but something was definitely lacking.

Beginning about 120 million years ago, the flowering plants (angiosperms, whose seeds develop within a protective ovary), with their brilliant yellows, blues, violets, reds and oranges, burst upon the scene, according to the fossil record. (But recent research suggests angiosperms may have originated much longer ago.) Their bright petals, scent-producing cells, nectar glands, and protein-rich pollen grains have evolved to entice animals to them and to inadvertently act as pollen vectors. The animals in turn specialized in feeding on flowers. Bees, flies, moths, wasps, butterflies, hummingbirds, and even bats changed with the evolving flower structures. Many plants and animals now depend on one another for survival. This evolutionary dance has resulted in an explosion of color and smell in our world.

Gymnosperms, especially conifers, are still common and very successful but have been outpaced by the angiosperms, which have spread to every conceivable corner of the earth. Flowering plants now make up over 90 percent of plant species. If success is measured by offspring, then we are truly living in the Age of Dandelions.

Contra Costa goldfields (Lasthenia conjugens) in Solano County. (Photo by Stephen Edwards)

The Bay Area is blessed with many wonderful places to see wildflowers. In Napa County just outside Calistoga is the Oat Hill Mine Trail. This old wagon road is steep, connecting with trails to Mount Saint Helena in Robert Louis Stevenson State Park, but the floristic reward is great—lupines, larkspurs, and many other species plus sweeping vistas. One of my favorite mid-April hikes is Chimney Rock at the westernmost tip of the Point Reyes Peninsula. Pussy ears, a lily that lives up to its name, are a favorite there, along with lots of Douglas irises and goldfields. Just south of San Francisco, San Bruno Mountain offers several unique plants and insects. Mitchell Canyon on the northeast lower side of Mount Diablo has fantastic displays of mariposa lilies. Edgewood Park in Redwood City is a small refuge with an abundant display of native flowers, including many adapted to the park’s rocky serpentine grasslands. Among these flowers are a few serpentine endemics—plants that can only grow on serpentine soil. Henry Coe State Park south of San Jose is HUGE!! But the rangers recommend Manzanita Point Road for the best display. Hiking here anytime is great, but the chance to see the gorgeous wildflowers of spring is dessert.

About the Author

Send your questions to Rosa-based naturalist Michael Ellis leads nature trips throughout the world with Footloose Forays (