Green Horizons

Usually, the most effective and cost efficient method for controlling invasive plants, such as amur honeysuckle, is by foliar application of herbicides directly to the leaves of the plant. And the best time of year for foliar applications is late summer into early fall, when plants are moving energy stored in their stems and leaves down into their roots.

Here are some quick tips to remember when applying herbicides.

First, READ THE LABEL! Make sure that the herbicide you are considering is not only labeled to control the invasive plant in question, but that it is also labeled for the site it will be applied.

Second, buy only what you need and use it all. Some herbicides are expensive and will lose their effectiveness if stored for long periods of time and exposed to extreme heat and cold.

Third, air temperature can be a factor. Herbicides are most effective in temperatures above 60 F (not a problem in late summer, but could be a factor if you were to get an early frost). If possible, avoid hot days when the temperature is above 90 F. Some herbicides will dissipate into the air before they are absorbed by the plant. Incorporating a spreader/sticker into the tank mix will help ensure the herbicide is taken up by the plant quickly.

Fourth, do not apply herbicides if rain is forecast within 24 hours. You will be wasting your time and money. Again, add a spreader/sticker to the tank to ensure rapid uptake.

Lastly, apply herbicides in the morning before the wind picks up. Drift is a big issue with foliar applications. Use caution in winds above 5 mph, and stop spraying entirely if winds exceed 10 mph.