How to kill honeysuckle roots: the steps Ohio State, Kentucky and UC publish

What is the first rule for killing honeysuckle roots?

Do not cut the shrub and leave it. Ohio State University Extension says: “Simply cutting the shrub off at the base will cause prolific sprouting and increase the number of stems.” It says an effective strategy for mature bush honeysuckle will deaden both the above ground part and the root system, which removes the chance of sprouting.

University of Kentucky says the same. Cutting the above-ground part alone is typically ineffective, and any control method must make sure the stumps are killed or removed.

Herbicide steps on this page follow the extension sources. They are not a substitute for the product label. OSU says: “Label recommendations must be followed to maximize the potential for successful control.” Follow the product label for the mix, the amount, protective gear and any limits near water, pets or other plants. Do not use a rate or product that these sources list unless your label allows it.

How do you treat a cut honeysuckle stump?

Cut the shrub close to the ground, then apply herbicide to the cut surface. OSU calls this cut stump treatment and says it works well on bush honeysuckle. University of Kentucky calls it the most common and effective approach for large plants. The steps below follow OSU.

1. Cut the shrub off close to the ground.
2. Choose the herbicide type. OSU separates water-carried products from oil-soluble products, and the choice depends on when you apply.
3. For a water-carried herbicide, apply it to the outer 1/3 of the top of the stump within minutes of making the cut.
4. For an oil-soluble herbicide, you can cut now and treat later. Apply it to the entire top and sides of the stump, but not to the point of excessive runoff, as long as the stumps are dry and not frozen.
5. Apply with a spray bottle, paintbrush, roller or wicking device, as OSU lists.
6. Follow the product label for the product, strength and safety gear.

University of Kentucky stresses timing: allowing the cut surface to dry will reduce herbicide effectiveness. It also says to avoid the method in late winter or early spring before leaf-out, because rising sap reduces the amount the plant takes up. OSU says late summer, early fall or dormant season applications have all been effective, and to avoid the spring sap flow.

This is the method the cut stump treatment glossary entry describes. For the plant itself, see the entry on honeysuckle.

What about foliar and basal spray?

Both are sprays for plants that are standing. OSU describes each and lists which products it recommends in its tables.

OSU warns that spraying plants that are hard to reach can damage or kill valuable non-target plants through drift or overspray. University of Kentucky says basal bark treatment is not recommended where honeysuckle grows among or under native trees, because the products could harm native plants.

How do you kill honeysuckle roots without herbicide?

Two methods appear in the sources: repeated pulling for small plants, and a black plastic cover for cut stumps.

Pull or dig small plants. OSU says pulling or digging of small plants is most effective after a rain, and is fairly easy because the plants are shallow rooted. It says essentially every root must be removed. If you repeat the work often, small shrubs can be eliminated once food reserves are exhausted. OSU says the key is to be vigilant.

Cover the stump. The University of Cincinnati reports that botanist Denis Conover shares a no-chemical method for homeowners. The steps in the article are:

1. Cut the bush and any branch shoots low to the ground.
2. Cover the stump and any exposed branch ends with garden plastic. Black garbage bags also work. Tie the plastic to the stump or secure it to the ground with garden wires.
3. Plant native trees or bushes around the dead stump to discourage honeysuckle from returning.

The article says covering the trunks in plastic, such as black garbage bags, and pinning it to the ground against the wind “effectively kills honeysuckle without chemicals.” It is a news article about one botanist’s work, and it gives no kill time. Read more in the post on the black plastic honeysuckle method.

How long do you need to watch for resprouts?

Watch for at least one year. OSU says: “Monitor treated plants for at least one year to determine if complete control is achieved.” Any plants that resprout or are not completely killed by the first treatment will need a follow-up treatment. University of Kentucky says follow-up visits are also needed to scout for new seedlings spread by birds and for plants missed the first time.

The sprouts that show up are a form of resprouting. The guide on whether a stump will grow back covers regrowth from tree stumps. For a plant that sprouts from the base, UK says to deal with abundant sprouts through foliar herbicide application when the shoots are small, again following the label.

What about grinding the stump?

The sources on this page do not cover grinding a honeysuckle stump, so none of them says it kills the roots. For more on what a grinder does to the roots, see the guide on whether roots die after stump grinding. The pillar on honeysuckle stumps and roots puts all the methods side by side. Ask about it when you request your free estimate.

Next step

Start with the pillar on honeysuckle stumps and roots. Call (513) 587-6772 or send photos for a free estimate.