You can remove tree stumps by digging the stump out or grinding it down, but these are labor-intensive tasks and may not kill the stump’s roots, which may then re-sprout. Stump-killing products contain herbicides that kill the stump’s roots and prevent regrowth. Although these products do not remove the stump, they are useful on stumps that are too close to structures, fences or other landscape features for mechanical removal.
1. Active Ingredients
Many of the stump-killing products available to homeowners are ready to use and can be applied directly to the stump without mixing or dilution. Some require dilution with water before application, but the rates vary from one product to the next. Common active ingredients include 2, 4-D, dicamba, glyphosate, imazapyr, picloram, and triclopyr. However, herbicides that contain 2, 4-D, dicamba, imazapyr or picloram as the active ingredient are non-selective herbicides that may harm nearby vegetation. Products that contain picloram are usually only available to professionals because of its potential to contaminate groundwater. Products containing triclopyr or glyphosate as the active ingredients are typically the safest and most effective herbicides available to homeowners.
Cut the stump as close to the grounds as possible and make sure the surface is level to prevent the herbicide from running off. On large stumps, herbicides should be applied inside the bark, where the living tissue is located. This will carry the herbicide’s active ingredient to the roots. In general, fall applications of glyphosate or triclopyr herbicides are most effective because the tree stumps are moving carbohydrates and proteins to their root systems at this time and will carry the herbicide as well. Both triclopyr and glyphosate must be applied to freshly cut surfaces. Drill two or three 1/2-inch deep holes into the bark of the stump to serve as reservoirs for the herbicide. Apply a ready-to-use herbicide containing triclopyr or glyphosate to these holes with a paint brush or a rag to avoid spray drift to surrounding vegetation. Repeat applications may be required if suckers or sprouts appear after application.
When using any stump-killing product, always wear a long-sleeve shirt, long pants, closed toe shoes, and nitrile or latex gloves. Wear safety glasses and any other protective equipment recommended on the product label. Read the product label instructions to determine first aid instructions and storage and disposal requirements. The label will also list hazards that make the product unsuitable in certain situations. Always read and follow the label instructions to ensure the product is intended for cut-stump application.
4. Dealing with Dead Stumps
It can take several years for a dead tree stump to decompose, but you can speed up the decomposition process using a rotting agent, such as potassium nitrate. Other stump-removal products may contain alkalis or sulfating agents that break down lignin, or enzymes that weaken the plant’s cell walls. General nitrogen fertilizers can also accelerate decay of wood stumps. Stump decay accelerator products are typically available in granular form. Drill several holes into the dead stump and pour the accelerator into the holes. Fill with water and leave the product to work. The stump will still take several months to decompose. A faster stump removal option is to rent a stump grinder to grind the stump down to soil level or hire a professional to remove the dead stump.
- Backyard Gardener: Killing Woody Stumps
- University of Arizona Cooperative Extension: Cut Stump Application of Herbicide to Manage Woody Vegetation
- University of Florida Extension: Herbicides to Kill Invasive Trees in Home Landscapes
- This Old House: Removing Tree Stumps
- Colorado State University Extension: Stump Removal
- Acorn Tree and Stump Services: Stump Removal Methods
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