What do I spray for that?
Published 7:43 pm Thursday, January 16, 2020
This time of year, with every passing warm day, a hot topic has been spraying herbicides on home lawns. I fielded this question three times this week. We have many tools that we can “spray,” sort of like saying, “There’s an app for that;” we have “icides” for many of the pests that pester us. We have pesticides, miticides, bactericides, fungicides, herbicides and insecticides — it’s enough to give you a headache-icide! So, what are all of these?
Some are self-explanatory, such as pesticides. This is a generic term that is used to describe any substance or mixture of substances intended for preventing, destroying, repelling or mitigating any pest (EPA definition). This term encompasses all of the above “-icides.”
How do you know what to spray for that? The first step to mitigating a pest problem is to know what you are dealing with through identification. Is it a disease problem in your tomato patch? You need to know: is this a fungal disease, bacterial disease or a viral disease? Of the diseases we deal with in the home garden roughly 80% are fungal. Fifteen percent bacterial, and 5% are viral. You cannot cure diseases, so it is important to use fungicides or bactericides to prevent the disease before occurrence. With viruses in the home garden, just like in humans, there is no cure or prevention for a virus.
Is it an insect or a mite? Many of the insects you find in your garden are not pests, many are beneficial. When we spray a broad-spectrum insecticide, we kill the beneficials, leaving our garden with more issues than when we started! For this reason, we need to make certain which “-icide” we need and for which pest we need it. Broad-spectrum and systemic insecticides will kill all insects in most cases and should be used with great caution. There are chemistries that are less potent, such as insecticidal soaps and horticultural oils that will help us to get rid of the “bad bugs” while protecting the “good bugs.” This is called integrated pest management.
There are pollinators to think about when spraying insecticides, as well. One of every three bites of food we eat requires animal pollination. I don’t know about you, but I like to eat fresh fruits and produce! One thing you can do is read the entire label of a product before you use it. Look for the Bee Icon on the label to ensure the product is safe for bees. Use your insecticides early in the morning or late in the afternoon when bees aren’t flying.
Let’s talk herbicides. There are selective herbicides and non-selective herbicides. Selective means that the product works on some plants and not others. An example would be using a sethoxydim (Poast) product to kill grass around your vegetables. This product will take care of the grass but not harm the vegetable plant. There are other examples that are not selective such as glyphosate (Round-up) that will kill almost everything it touches. It is very important to identify the weed you are trying to kill and make sure the chemical you are using is labeled for the weed and the plant you wish to keep. There are products that will be safe for some grass or vegetables that are harmful to others. Pay very close attention to the Return Entry Interval (REI) and the Preharvest Interval (PHI) on the label to know when it is safe to enter and safe to harvest after a pesticide application. Make sure to read the entire label: the label is the law!
If you have a question about an “-icide” be sure to contact your local N.C. Cooperative Extension Center. There is an N.C. State Pesticide School coming up on Feb. 18-19 at the Beaufort County Community College. Sign up now to get your pesticide license! For those Interested in becoming a Master Gardener, there is going to be an Extension Master Gardener Volunteer training series this spring. Sign up for our information list at go.ncsu.edu/bocoemginterest to receive updates. Call the Extension center today at 252-946-0111 to learn more or visit the Blacklands Area Horticulture page on Facebook!
Gene Fox is the area consumer horticulture agent with the North Carolina Cooperative Extension.