The mimosa tree originated in China and was brought to the United States in the 18th century. Its fuzzy, pink flowers and feathery, green foliage make it a striking and unusual ornamental. The plant spreads rapidly through seeds that grow from split-open pods and is considered an invasive plant, according to Florida's Center for Aquatic and Invasive Plants. Frequent attempts to cut it down can prove unsuccessful, as it will often spring up again from the root system.
Dig up smaller mimosa trees with a shovel. This practice is often called grubbing. To do this, insert your shovel into the ground in a circle around the mimosa to carve the root ball from the surrounding soil. Then scoop up the tree, roots and all. Shake the trunk to dislodge dirt from the roots and replace the loose dirt into the hole left by the tree.
Apply a systemic herbicide such as glysophate or triclopyr to intermediate-sized trees to kill them. To do this, purchase an herbicide that comes with a spray applicator and spray the entire tree including trunk, limbs and foliage. Do not apply on a windy day because the spray can drift onto surrounding vegetation.
Girdle trees that are too large to be sprayed. To do this, cut a groove into the trunk surrounding the tree approximately 6 inches above the ground with a hatchet. This groove should cut through the bark and into the trunk itself. This prevents water and nutrients from reaching the tree, slowly choking it.
Cut down larger trees at ground level with a chain saw when they start to flower. Do not cut them when they have produced seed pods because the seeds will scatter and produce more mimosas.
Apply a systemic herbicide to the cut stump to kill the roots of the tree. It may take several applications of systemic herbicide to completely kill the tree.
Continue to cut down suckers from the trunk until the mimosa roots have completely died.