The Mimosa tree, or Silk Tree (Albizia julibrissin), is a species native to Asia, widely introduced for its delicate, pink, powder-puff flowers. Despite its ornamental appeal, this fast-growing tree is now considered an invasive species across much of the United States. Its tendency to produce copious seed pods and its vigorous habit of resprouting from the roots create significant maintenance issues. Successfully removing and preventing the return of a Mimosa requires mechanical cutting combined with targeted systemic herbicide application to neutralize the aggressive root system.
Preparing for Initial Removal
Permanent Mimosa tree removal begins with the physical reduction of the above-ground biomass. Before starting, wear appropriate personal protective equipment, including safety glasses, heavy gloves, and sturdy footwear. The optimal time for this mechanical removal is late summer or early fall, coinciding with maximum nutrient translocation down to the roots. Cutting the tree then ensures the subsequent herbicide treatment is drawn deeply into the root system. The trunk should be cut as close to the ground as possible to create a low, level stump for easy treatment. Felling the tree without chemical follow-up will stimulate the roots to produce multiple vigorous sprouts, worsening the problem.
Systemic Herbicide Application Methods
Killing a Mimosa tree requires systemic herbicides like triclopyr or concentrated glyphosate, which travel through the plant’s vascular system down into the roots. These chemicals must be applied directly to the living tissue to be effective. Always consult and follow the manufacturer’s directions regarding safety, dilution, and application rates before handling any chemical product.
Cut-Stump Treatment
The cut-stump method is the most reliable technique for a freshly felled Mimosa tree. It involves immediately applying a concentrated herbicide solution to the stump’s newly exposed surface. Application must occur within minutes of the cut, ideally within five to fifteen minutes, before the tree seals the wound. The herbicide should be applied only to the cambium layer, the narrow, light-colored ring of living tissue just inside the bark. Use a 20% to 50% concentration of glyphosate or a 50% solution of triclopyr. Painting the solution onto the outer ring ensures the chemical is absorbed by the phloem, which transports the herbicide to the roots.
Frill or Girdling Method
For larger trees where immediate felling is impractical, the frill or “hack-and-squirt” method allows for standing treatment. This technique involves using a hatchet to make a series of downward-angled, overlapping cuts (frills) completely around the circumference of the trunk near the base. The cuts must penetrate the bark and the cambium layer to reach the sapwood. Concentrated herbicide, such as triclopyr or glyphosate, is then squirted or painted directly into each frill. Apply approximately one milliliter of undiluted herbicide into each cut, spacing the cuts about one inch apart. This allows the herbicide to enter the sap stream and be distributed throughout the tree, leading to the demise of the root system.
Basal Bark Treatment
The basal bark treatment is suitable for smaller trees or saplings with smooth, thin bark, typically those less than six inches in diameter. This technique utilizes an oil-soluble formulation of triclopyr, often diluted in a penetrating oil or diesel fuel, at a 20% to 30% concentration. This solution penetrates the outer bark without requiring any cuts. The mixture is sprayed or painted completely around the entire circumference of the lower twelve to eighteen inches of the trunk, ensuring the bark is thoroughly saturated to the point of runoff. This application is best performed in the fall or winter when the bark is driest and absorption is more effective. Treat the entire area down to the soil line for effective translocation.
Managing Suckers and Seedlings
The Mimosa tree is notorious for producing suckers from the surviving root system and abundant seedlings from its long-lasting seed bank. Even after the main trunk is treated, follow-up maintenance is mandatory for several growing seasons to achieve complete eradication. Suckers should not be removed by mowing or simple cutting, as this encourages the remaining root fragments to produce more shoots. Instead, treat each sucker individually using a spot application of concentrated herbicide directly onto the foliage or a freshly cut stem. Hand-pulling is the most effective way to remove new seedlings. Seedlings are easiest to pull after rainfall when the soil is loose, but ensure the entire root is extracted to prevent resprouting.