Will Grazon Kill Trees?

Grazon is one of the widely used herbicides for woody and hard-to-kill weed removal. There are a few versions of this herbicide available in the market. But how effective is Grazon at killing trees and what is the correct method of using it? Let’s take a look.

Grazon is a commonly used weed controller and it is effective on a wide range of species. However, it won’t be able to kill small to medium-sized trees. Its effectiveness caps out at plants up to 10-13 feet tall. Grazon Extra should be sprayed on the foliage of the targeted species for it to be fully absorbed and effective.

grazon can kill trees?

What is Grazon?

Grazon is a systemic herbicide developed by Corteva Agriscience for controlling the growth of hard to kill noxious and woody weeds. Grazon majorly comprises three chemicals: Triclopyr, Picloram, and Aminopyralid.

The updated version of Grazon is known as Grazon Extra which was previously known as Grazon P & D. The usual method for delivery is foliar spraying and it covers a very wide range of weeds without affecting the pasture grasses.

Grazon Extra works through targeting both the foliage and the roots which result in rapid browning of leaves, stems and ultimately lead to the root system completely dying.

Some of the weeds on which Grazon Extra is commonly used are Blackberry, Capeweed, Docks, Eucalypt regrowth, Fireweed, Prickly Pear among others.

Can Grazon Be Used To Kill Trees?

Although Grazon Extra is really effective on small woody weeds and plants, it will not be able to kill any small or medium-sized trees. It is not considered to be a very strong herbicide and even excessive use of Grazon Extra will only lead to the browning of some leaves and branches but it won’t be able to kill any large trees.

The usual height of plants on which Grazon is recommended caps out at 10-13feet.

How To Correctly Use Grazon?

Before using Grazon Extra make sure to take all the safety precautions such as wearing full-sleeved cotton shirt, long pants, protective gloves, and mask. You should also wear a washable hat to protect your hair from coming in contact with the herbicide.

For most species of weeds, 350-500ml of Grazon Extra in 100 L of water should be enough. But make sure to read the label of the herbicide before making the solution. The company’s website also provides information regarding the concentration needed for handling different species.

Use clean water for the mixing process for best results. Hard or overly alkaline water can reduce the effectiveness of the herbicide. While mixing, fill the tank halfway with water and then add the herbicide before adding more water.

If you need to add some other wetting or penetration agent for some particular weed population, add them once the tank is filled with the water solution. The water-Grazon solution can be used for up to 7 days once prepared, although it is recommended to use it as soon as possible.

How to Apply Grazon

Grazon Extra should be applied through the Foliar Spray method. As it is systemic in nature, it will be absorbed by the leaves and the stems and carried all the way to the roots to kill the plants.

You will need a portable sprayer for covering the foliage of the leaves with the herbicide solution. For large-scale use, you will need a more robust pump to get the job done.

Make sure that the plant or the weed is not covered with water. This will lead to a reduced absorption rate. Also, be wary of the weather, even if the wind is mild, then the herbicide can get carried away. Also if you think it is going to rain in the next two hours, then hold off the spraying process.

While spraying the herbicide, cover the entire foliage of the weeds till the point of run-off. You should be able to see the herbicide dripping from the leaves. Treat the stems and the roots as well if they are visible.

One acre of blackberry, for example, can end up taking 1000-1500L of solution to get completely covered. This amount can change slightly depending on the species you are dealing with.

What Are The Health Hazards of Using Grazon?

Grazon Extra is classed as a poison, upon contact it can cause eye and skin irritation. And it can be especially dangerous in concentrated form.

If the herbicide comes in contact with your skin or eyes, run the affected area under cold running water for 15 minutes and contact a physician immediately.

What Are The Environmental Effects Of Using Grazon?

A lot of fruit trees, grapevines, and legumes are susceptible to Grazon Extra. Be very careful while spraying the herbicide near wanted and desirable plants. Try to use the wind to your advantage to direct the spray in the opposite direction.

The effects of Grazon can stay in the soil for up to 6 months, keep this in mind while planting any new vegetation or using the soil or existing vegetation for any mulch or manure. Animals should not be allowed to munch over the applied area for at least a couple of months.

More reading: Will roundup kill trees?


Grazon Extra is an excellent growth controller for woody and noxious hard to kill weeds but it is not effective for killing bigger trees. The herbicide is only effective on weeds and plants up to 10-13 feet tall. You can use Grazon Extra by spraying the solution over the foliage and the stems of the plants.

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