Eastern Redbud: Early Flowers Mark the Beginning of Spring
By T'ai Roulston, Curator
The eastern redbud (Cercis canadensis) is well loved, commonly planted, and native to most of the eastern United States. It has few detractors, mainly contrarians that denigrate anything common and literalists who find the buds and flowers not sufficiently red to earn the name. Aside from these minor blemishes, it is a plant to behold, propagate and appreciate, from both an aesthetic and an ecological viewpoint.
As a wild plant, it is home in open woodlands, especially the edge where forest yields to field or roadside, lots of light but not too dry. As a small tree, it goes unnoticed until just before bloom, when the rose-pink flowers burst from clustered buds along the stems. Their sprays of color stand out even more when the backdrop is leafless trunks of oaks and maples, a wispy pink before a wall of gray. As much as we appreciate it, we are not their biggest fans. The eastern redbud is a key floral resource for many of our bees.
When the redbud blooms, in March or April depending on the spring, bumble bee queens have just emerged from a hole they dug last fall and seek to start a colony. At first, they feed themselves on nectar and pollen and then they search the ground for an abandoned mouse nest or some other hidden cavity to rear their young. When that is found, they collect nectar and pollen to feed their first workers, which they alone must rear for several weeks. It is a dangerous time to be a bumble bee queen. They must leave their nest to forage, leaving no protection for their developing offspring. They themselves are large and plump, a tempting morsel for a hungry bird, so each time they leave the nest they risk their own life and that of their offspring. So at that time of year, finding plants with lots of flowers rich with pollen and nectar is key: the more flowers in the landscape, the less time they and their offspring are exposed.