Nature Spaces

Mimosa (Albizia julibrissin) or Silk Tree is blooming along roadsides, forest margins, and streams. Their fragrant, pompom-like flowers make them easy to spot in late May and June. Mimosa is native to China and has been widely planted as an ornamental. Unfortunately, it readily escapes yards and invades natural habitats far away from where they were planted. For instance, I photographed this Mimosa at a land conservation park in my area.

Mimosa is listed as an invasive tree in several southeastern states (SC, GA, KY, VA, and TN are a few examples). Much of its spread is into sunny disturbed areas, woodland edges, streambanks, and rights-of-way. Once established, Mimosa re-sprouts from its roots, making it difficult to eradicate. The fruits and seeds are dispersed by the wind and also float on water, sending seeds from neighborhoods into street gutters and down storm drains where Mimosa then spreads downstream. Unfortunately, Mimosa has become a common, and sometimes dominant, tree in many woodland edges and streambanks across the Piedmont. Because most native insect are specialists of native plants, the more Mimosa spreads, the less habitat there is for our native insects. You will occasionally find caterpillars feeding on Mimosa, but they’re often mimosa webworms (Homadaula anisocentra), which are also introduced from China.

While the Mimosa flowers do provide nectar for a short time for some pollinating insects and ruby-throated hummingbirds, there are many native plants that fulfill this role without causing degradation to our southeastern woodlands (our native wildlife survived here long before mimosas were introduced). As with other introduced plants from China and elsewhere, Mimosa has little benefit to our natural food webs as few caterpillars consume the leaves. This means that natural areas invaded by Mimosa have less food available for songbirds and other wildlife native adapted to the southeastern United States. Mimosas simply contribute to a “food desert” for our native wildlife.

Rudbeckia maxima (Giant/Swamp Coneflower) is in full bloom. This striking perennial wildflower is only native to East Texas and a bit of each adjoining state. My patch out front came from seed collected from a patch behind my parents which came from a patch in their previous perennial border which came from a patch in an older perennial border which came from a single plant a friend of my Grandmother Emanis' shared with her years ago which grew behind this very house. It's a great garden perennial but more popular in Europe and the Northeast than where it's native.