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When To Apply Brush Killer [And How To]?

It is difficult to remove unwanted trees and vines that randomly grew in your garden. Good thing you heard about brush killers so you can get to the root of the problem and rid your garden of these plants. If you don't know when and how to use these brush killers, you're on the right page. We asked the experts about your concerns and here's their reply. 

The best time for brush killer application would depend if it is a pre-emergent or post-emergent herbicide. Use pre-emergent brush killers in late winter or early spring. Apply them to the soil. Post-emergent herbicides are best used in spring, summer, or fall as long as the plant is in active growth. These are applied to the foliage of the plants or stumps of trees.

Keep on reading to know more about the proper application of brush killers and read some tips on how to prevent an invasion of these unwanted plants later on. We'll also tell you how these chemical herbicides work. Let's get going!

Man spraying pesticide with portable sprayer to kill weeds in the yard, When To Apply Brush Killer [And How To]?


What is the best time of year to use brush killer?

Having unwanted trees and vines growing in your garden can make your property look unsightly. They would look out of place in your well-coordinated space. They also take up nutrition that's meant for your beloved plants. Some are even harmful to you or your plants. That's why you need to get rid of them as soon as possible.

Senior gardener spray herbicides to kill weed in green lawn in garden

Some machines can help you with this task, especially if you're dealing with larger trees. Or you can also do it the hard way by manually cutting or pulling the undesired plants from the place where they sprouted. Either way, it is pretty much a challenging task as you have to make sure that you remove everything from the tip to the roots so that they won't bother you again.

And the thing is, these efforts are oftentimes ineffective because just when you thought you've gotten all the roots out, it would turn out that you didn't catch everything after all.  

Well, you can end your garden woes with the use of a brush killer. These are chemical herbicides that can help you get rid of your problem with these invasive brushwood plants that can be in the form of vines, saplings, conifers, or trees.

Check out this brush killer on Amazon.

But before you get all excited, it's important to know the best time for their application so that you can maximize their effectiveness. The thing is, there are different types of herbicides and the type of herbicide that you use would determine the season when it is best to apply it to the plant.

Types of Herbicides

Herbicides are typically classified into two - selective and non-selective. Non-selective herbicides will kill any plant that they come into contact with. Selective herbicides are only intended to affect certain plants.  Manufacturers provide a detailed list of these plants where their products would be effective.

Selective herbicides are further grouped into two categories. This is crucial in determining the best time for their application. Pre-emergent selective herbicides are intended to kill young plants as soon as they germinate from the seed. This treatment is applied to the soil. This type of herbicide is best applied in the late winter or even early spring when the plants are beginning to develop.

Click this link to find this pre-emergent herbicide on Amazon.

On the other hand, post-emergent herbicides kill plants that have already developed. These are applied to the foliage of the plants and are best used in springtime when the plants are already growing in your yard. But you can also use them during summer and fall or as long as the plant is in its active growth phase.

Find this post-emergent brush killer on Amazon.

There you go. You need to know the type of herbicide that you're using so that you'll be able to apply it at the right time in the brush's stage of development to get the best results. 

How to Apply Brush Killer

Spraying pesticide with portable sprayer to eradicate garden weeds in the lawn

There are different types of brush killers out there. As mentioned earlier, the type of herbicide you use will not only determine the best time of application but also the manner of application.

Pre-emergent herbicides are applied to the soil while post-emergent brush killers are sprayed or brushed on the plant's foliage or tree stump.

Here are the steps to applying a brush killer.

  1. Identify the brush type that's present on your property. This will help you determine the right product to use for its proper treatment.
  2. Inspect where these unwanted plants have sprouted and the extent of their growth. Take note if they are right beside crops or ornamental plants that you're taking care of.
  3. Choose the right product or herbicide that will help you treat the specific brush type that you're dealing with. If the brush is right next to your precious plants, choose a selective kind of herbicide so that it'll only kill those plants that you want to get rid of.
  4. Cut off as much of the tree, shrubs, or vines as you can.
  5. Choose a calm and mild-weather day for your herbicide application. Do not apply brush killer on a windy day to avoid it from spreading elsewhere and rain shouldn't be in the forecast to avoid diluting the herbicide.
  6. Wear gloves and protective clothing.
  7. If you're not using a ready-to-spray formula, prepare the herbicide according to package instructions.
  8. Put your prepared solution in a water sprayer to make it more convenient for you to apply the herbicide to the brush.
  9. Depending on the herbicide type, spray it on the soil or the foliage. Cover as much area as possible. If treating trees, apply the solution on the stump ensuring full coverage.
  10. You can also use a paintbrush to have more control when applying the brush killer to the leaves and stumps of the undesired plants or trees.
  11. Take extra care not to put brush killer on other plants. You can cover them with newspaper or plastic in the meantime.
  12. It's best not to water and limit access to the treated area for at least 4 hours. This will give the soil or plants time to absorb the herbicide.
  13. Reapply after 1 to 2 weeks if needed.

That's it! This will make getting rid of invasive and undesirable brush easier.

How to Prevent Brush Invasion

Dandelions in partially mowed front yard lawn grass

Trust us, you don't want to go through the steps detailed above or if you've already done it, it's an experience that you don't want to repeat. That's why it's best to take the necessary actions to prevent a brush invasion on your property. Here are some tips for you.

  • Use a soil sterilant along your fence lines. This will prevent unwanted plants from your immediate vicinity from growing in your place. 
  • Always monitor your garden or lawn for any sign of unwanted brush. Early detection makes it easier to get rid of these plants while they haven't invaded your property yet.
  • Remove trunks and dig the roots of the undesired plants so that they won't grow again. Fill the space they previously occupied with dirt or soil that's not conducive to plant growth.
  • Prune your plants regularly and always clear your property from garden waste to prevent the regrowth of these woody plants.

These are just some of the preventive measures that you can take to avoid dealing with this kind of problem.  

How does brush killer work?

Spraying herbicide on dandelion

Brush killers are chemical herbicides formulated to kill the unwanted plants on your property. There are different manufacturers of these products and each one may use a different active ingredient.

Brush killers usually contain any or a combination of the following:

  • Triclopyr. This is a selective herbicide that works great on woody plants such as sweetgum and mesquite.
  • Fluazifop. This is another selective herbicide that's often added to other herbicides making it more effective in getting rid of a stubborn brush.
  • 2,4-D. It is usually added to Triclopyr to be more successful in eradicating broadleaf weeds that have invaded your property.
  • Glyphosate. This is a potent non-selective herbicide so be careful with your application.

These types of herbicides are systemic. They are absorbed by the plants and their active ingredients travel throughout the vascular system, killing the plants entirely including their roots so that they will not grow again.

The rate of their effect on the plants would also vary from one product to another. Some promise visible results in a day or two while you have to wait for weeks, especially when treating trees, thicker and more invasive brush.

Final Thoughts

Just remember, the best time to apply pre-emergent herbicide is in late winter or early spring as the plant is about to grow. Apply this type of brush killer to the soil. Use a post-emergent herbicide in springtime as the plants develop and apply it to their foliage for optimum results.

For more resources on how to keep unwanted plants out of your garden, you can visit the following posts:

How To Remove A Holly Tree Stump And Roots

How To Destroy Ground Covers—Without Harming Other Plants!