Smooth Bouvardia - 2009
By Doug Moore
Recently on the upper Proctor Loop I noticed a flash of motion near a splash of bright color in the woods some yards ahead. A closer look through my binocs revealed the flash as a regal male White-eared Hummingbird. The splash of color was a lovely cluster of orange-red Smooth Bouvardia flowers attracting the hummer in for a quick drink. My first thought was, “White-eared Hummingbird!” My next thought, several stunned seconds later, was, “Hey, cool, this is the first time I’ve ever seen one feeding at native flowers and not at a feeder in someone’s yard!” As the bird zipped off up-canyon, I could not help but be thankful that Madera Canyon has so many wonderful plants, like Smooth Bouvardia, that are not only beautiful, but help attract amazing critters like White-eared Hummingbirds!
Smooth Bouvardia, Bouvardia ternifolia, is truly an elegant plant and one of Madera Canyon’s more common shrubs. On the small side, Bouvardia only grows three feet tall, rarely as wide and is deciduous. Found from 3,000 to 9,000-feet elevation on wooded slopes and canyon bottoms, the plant prefers partial shade. It is particularly abundant along Madera Creek from Proctor to the Mt. Wrightson Picnic Area. In her book, MaderaCanyon Wildflowers, author Joan Lewis lists finding Smooth Bouvardia on all canyon trails.
In spring, the plants sprout bright green, lance-shaped leaves in whorls of three to four. The leaves are up to three inches in length and often covered in soft minute hairs. With the onset of summer, the Bouvardia show really begins! From May to October Smooth Bouvardia erupts into bloom, producing clusters of bright orange-red tubular flowers from stem tips. The upright narrow blossoms are up to 1¼ inches long and flare into four or five tiny lobes. Hummingbirds and butterflies, particularly Cloudless Sulphur and Southern Dog-face, appear to be the primary pollinators attracted to the conspicuous flower clusters.
Smooth Bouvardia is also the sole larval food plant of the Falcon Sphinx Moth, Xylophanes falco. Like many moths, the monsoon-flying adult is handsome, but modest, in shades of gray lined with black and white. The caterpillar on the other hand, is one of the most spectacular insects in Madera Canyon! The two- to three-inch larvae come in two color forms- bright leaf-green or dark gray-green running to black, and sport a flexible horn at the tail. Both forms are stippled in rows of tiny white dots with six large white spots running down each flank and striking false-eyes of black, yellow and turquoise just behind the head. Mature caterpillars descend from the plant to dig down into soft soil to pupate.
Smooth Bouvardia is easy to spot by looking for the unmistakable flower clusters. Look for Falcon Sphinx caterpillars in August and September on partially defoliated plants; the larvae are often conspicuous, but may hide among remaining foliage. Use a bit of caution when looking for Smooth Bouvardia, particularly along streambeds. A preference for partial shade sometimes results in the shrub growing amidst patches of Poison Ivy!
Photo by Doug Moore