Box Elder

Asked May 4, 2015, 7:51 PM EDT

Tree shoots all through my yard.How do I get rid off them

Huron County Michigan trees and shrubs

1 Response

Generally, boxelders are a sign of heavy, wet soil, and a high water table. They are one of those healers of disturbed land that get dismissed as "weed trees" by so many. The boxelder is a very opportunistic species. It grows just about anywhere in Michigan and it can out-compete and overgrow many other tree species. If you cut it down without treating with herbicide, it will grow back from the stump or roots.

Boxelder is highly sensitive to 2,4-D and also is susceptible to fire and mechanical damage because of its thin bark.

Hand pulling is one option. However, other than ripping out the box elders, allow them to leaf out this spring and then cut them back to the ground. The leafing out will spend the carbohydrate reserves from last fall, so the trees will be too weak to releaf to any great extent. Whatever does pop up again can be nuked with any of the following methods.

If you just have new seedlings popping up in your lawn, you can spot treat. Isolate the seedling (placing a plastic bottle with the bottom removed over the seedling), and spray through the top, an herbicide which contains an active ingredient such as glyphosate, as in Roundup, Kleen-up, Mirage, etc. or perhaps triclopyr, such as Brush-B-Gon, or 2,4-D found in Crossbow. These are not recommended products, just a number of examples. These foliar sprays can also be used on freshly cut stems of stumps of woody plants. There are many products that have these claims, so always read and follow the label instructions before use, and make sure they claim to do what you want them to do.

Warning: If the seedlings are attached via the root system to the mother tree, then some damage could be expected to that tree.

Spot treatment with fire may be another option. A propane torch with a long wand works well in these situations and care must be used to treat individual trees or small groups of trees. This technique works especially well on seedlings and young saplings, and is generally less labor-intensive than hand-pulling and less expensive than herbicide treatments. Spot burning often only top-kills more mature trees.

To burn invasive plants with a propane torch, you must pass the flame over the plant for less than one second, which is enough time to boil the water in the plant. This will cause the plant to droop immediately and die within a couple hours.

Do not use propane torched on dry vegetation or when windy conditions exist unless you have made adequate preparations to contain a runaway fire.

Be sure to check with your township to see if this type of burning is allowed.


Additional Information:

Boxelder, ash-leaved maple (Acer negundo)

Although this tree is a native, it is often invasive due to its prolific seed production, its shade tolerance and its ability to send up many vigorous resprouts when cut. Cutting can be a tool to remove large, seed-bearing plants, but treatment of the cut stump with an appropriate herbicide is needed to kill the root system. Boxelders are dioecious, meaning the individual plants are either male or female. From about August through much of the winter you can identify the female trees by the clusters of seeds (called keys, samaras or those “winged helicopters”). If you are concerned about controlling the spread of these trees into nearby fields, prairies or open land, you should concentrate your initial efforts on controlling the seed production of the female trees. Either cut or girdle these trees first to stop the spread of seeds. Basal bark spraying is the most cost-effective method to selectively remove boxelder from areas where they are mixed with desirable trees. Individual stems six inches or less in diameter can be sprayed on the stem of the standing plant. Spray from the base of the plant to a height of 12 to 15 inches from the ground. A low pressure backpack sprayer works well for this job. This can be done any time of year, even when snow prevents spraying to the ground line, as long as you can spray the 12 -15 inch band below the first branch (called stem banding). Stems six inches or more in diameter should be girdled or frilled (to expose cambium) and then sprayed. Where fields have been invaded by boxelder, the treatment to eliminate the trees will depend on their size. For small trees less than 2 feet tall, foliar spraying with a broadleaf herbicide will selectively kill the boxelder without harming grasses. Be aware that other broadleaved plants (forbs, shrubs and trees) will also be killed. If the trees are larger, more than 2 feet tall but less than 1½ inches in diameter, a “brush hog” style mower can be used to cut the trees, followed by spraying with a broad-leaf weed killer when the trees resprout from the cut stubs. For large trees (greater than 2 inches in diameter), the trees will need to be hand cut and stump sprayed or basal bark sprayed (6 inches in diameter and less). If you need to do this work once, it’s unlikely you will let it get to that point again.

Removal Recommendations:

Basal bark and cut stump spraying-

Garlon - Using diesel fuel, fuel oil, kerosene or a commercial bark oil diluent, mix a 10% solution of Garlon 4, Element 4 or Tahoe 4 (active ingredient triclopyr). For a four gallon backpack tank this would be 0.4 gallon of Garlon or Tahoe 4 plus 3.6 gallons of diluent. Pathfinder II is triclopyr in a ready-to-use (RTU) form. It can be used for basal bark and cut stump treatment of boxelder.

Crossbow – This is a mixture of triclopyr and 2,4-D. Mix it as a 25% solution with an oil-based diluent for basal bark or cut stump treatment.

2,4-D – This is available under several brand names, sometimes mixed with Dicamba, and is available at most hardware and farm supply and garden stores. Make sure you use the ester formulation for cut stump or basal bark treatment. Keep in mind that you may need to conduct follow-up treatment as this active ingredient is less effective than triclopyr.

Foliar treatments –

Garlon - Use a solution of 2% triclopyr, with water and a surfactant during the growing season. This method will kill all broadleaf plants and non-target plants can be damaged or killed due to drift. This method is most appropriate for a large number of seedling boxelders (i.e. field invasion from fencerow trees).

Crossbow – Mix a 4% solution with water as a foliar spray during the growing season. Watch out for non-target plants.

Mechanical Methods –

Mowing or Cutting – Depends on the size of the trees. See recommendations in the paragraph above.

Girdling – Chainsaws can be used to cut or girdle larger trees. When girdling trees, make two rings, at least one inch deep, and three inches apart, completely encircling the tree. The girdle cuts need to be treated with an appropriate herbicide to kill the root system.

Prescribed Fire – Smaller plants (seedling to 1 inch) can be killed by spring or fall burns, but larger plants usually survive. Fire is best used in fire-adapted communities such as prairies and savannas. Burning should only be done using the advice of an expert consultant and following local ordinances and permit processes!

Overview:

  • Eliminate the large, seed-producing plant first.

  • In smaller areas, young trees can often be dug or pulled out. Larger plants may need to be cut close to the ground as possible. Resprouts, which can be numerous, sometimes must be cut repeatedly for several years during the growing season in order to totally kill the plant. Cutting trees after full-leaf expansion may result in less sprouting than if they are cut while dormant.

  • Most will resprout after being cut unless an herbicide is applied to cut surfaces.

I hope this information was helpful. Feel free to contact us again if you have further questions.