Asian longhorned tick. Photo by Center for Disease Control. By Caroline DurhamWarmer weather is just…
Some accounts say mimosa trees were introduced to the United States by French Botanist Andre Michaux in 1787. From his nursery in Charleston, South Carolina, Michaux shipped North American plants to France and imported species from around the world. Michaux brought mimosa seeds back to his nursery from Persia. However, the mimosa tree is native to central China, Japan, and southern Korea. Unlike the favored cocktail drink, the vigorous growing mimosa (Albizia julibrissin) is an ecological threat to native species.
Impacts of Mimosa
After gaining fame as an ornamental plant in 1807, this silk tree quickly overran and choked out native plants and prevented the regeneration of native species. Two hundred years later, mimosa is found across the United States and is a fixture of the Southern landscape. Its double compound leaves, with many leaflets, almost resemble a fern or honey locust. In the summer, the mimosa blooms, revealing the distinctive silky pom-pom-like pink flowers that are omnipresent, rippling in the breeze. The small tree can reach up to 40 feet and is found in disturbed soils along roadsides, forest edges, vacant lots, and riparian zones. It flowers abundantly in full sun and well-drained soils, although it does tolerate partial shade, drought, wind, and salt. Despite its beauty, mimosa is an invasive species that proliferates in many soil types. It multiplies much quicker than native plants, thereby inhibiting their growth with shade from its umbrella-like crown. It is a prolific spreader, producing long brown seed pods which prevail throughout winter. As a member of the Fabaceae family, mimosa is a legume and can fix nitrogen. While this is favorable for the mimosa, its leaf litter creates an excess of nitrogen, inhibiting the growth of native plant species, some of which provide a food source for animals.Removing mimosa
Mimosa is a prolific seed disperser. Each flower creates a seed pod of up to 12 seeds that can remain viable for years. Like most weeds, your best bet at controlling mimosa seedlings is to catch them in their earliest stage. Saplings will often sprout around the parent plant in the early summer. Mimosa also spreads by suckering and will quickly resprout if cut. Still, seeds can disperse over long distances if near running water. Additionally, the seeds contain a toxin that can harm animals when ingested. Small plants can be easily pulled, especially after a rain while the soil is still moist and will quickly release the sprout. When it comes to an established tree, the U.S. Forest Service recommends cutting it down as an initial control measure. Applying an herbicide to a freshly cut mimosa stump is the only way to kill the tree and prevent it from resprouting. When herbicide use is impracticable, girdling can be effective on more giant trees.Controlling Mimosa growth
Like kudzu, mimosa is a staple ingredient in Traditional Chinese medicine. Its earliest use was as an antidepressant in 200 AD. The flower was dried and used in tea to "harmonize the heart and will and make one happy and worry-free." I made the tea by following the ancient traditional Chinese medicine method. While the tea does not taste appealing, it's remarkable to note that the traditional medicinal use of mimosa persists in its native range. The bark from the tree functioned as an analgesic in healing bruises and fractured bones. Thankfully, mimosa is a short-lived plant as it is highly susceptible to fusarium wilt and has fragile wood. If you can't beat them, eat them! Fighting invasives by eating them is a fun countermeasure with sometimes tasty benefits. At the very least, you can enjoy some gastronomic experiences that could help curb invasives like mimosa trees. If you're so inspired, you can make a simple tea from the tussle of flowers, a recipe inspired by ancient Chinese medicine. The pink flowers can be picked and steeped in hot water for tea accentuating the flower's sweet gardenia and citrusy smell. You can also use the flowers to place on top of cocktails and cakes as a bright decorative pink pom-pom. Picking the flowers is necessary for preventing seed production, as the seeds are prolific and remain viable for 5-10 years.