Responsible Pesticide Use Benefits Everyone
Author: Michele McCawley, Consumer Products Marketing Manager, PBI/Gordon
As more and more of us share concern about taking care of our planet, questions arise as to how best to balance environmental responsibility and pest management. If all pesticide use were to cease today, we would not be prepared to check the rapid spread of harmful insects and noxious weeds that threaten our land and the people, native plants and animals it supports. In this article, we will share common characteristics and uses of some of the most common weed and insect controls. We’ll also share several tips on how to be the best and most responsible user of these products so that you can enjoy a pest free summer.
The world’s most commonly used herbicide is glyphosate, best known as Roundup, Pronto Big N’ Tuf, KillzAll, Honcho and more. Glyphosate is a non-selective herbicide, which means it kills all vegetation. It has very little toxicity to people and animals and when it comes in contact with the soil, it either becomes inactive or breaks down and disappears. Glyphosate, when used as the label directs, can be used for all kinds of projects including lawn, pasture and food plot renovation, vegetation control around outbuildings and fence lines, weeds growing up in patios, driveways and sidewalks, even for controlling weeds on the shorelines and in ponds and lakes. The biggest problem associated with glyphosate use is accidentally spraying it on things you don’t want to kill. To prevent costly mistakes, avoid spraying on windy days and near desirable vegetation such as ornamentals, flowers and vegetables. When spraying in plant beds, be careful to avoid contact with desirable plants. Also, don’t use in lawns unless you want to renovate and reseed as it kills the grass and will leave you with dead brown patches.
2,4-D is the most well researched and tested homeowner herbicide in use today. Years of scientific research has shown it to be an effective, economical weed control. Although sometimes used alone, it most often is purchased in combination with other herbicide ingredients and sold under brands such as Weed-Be-Gon and Trimec Lawn Weed Killer. It is broken down by microbes in the soil, usually in less than one week and is a “selective” herbicide, meaning it controls certain plants; in this case, broadleaf weeds like dandelions, plantains and clover in lawns. These products do not harm most grass, making them ideal for lawn weed control. When spraying a product containing 2,4-D, allow the lawn to dry before allowing anyone back on the treated grass. Do not spray flowers or vegetables because although it will not kill grasses, it can damage or destroy flowers, vegetable, ornamentals and other plantings.
MSMA is unique in that it controls some grassy weeds without harming lawn grasses. It is often found in crabgrass and nutsedge herbicide products to control both broadleaf and “grassy weeds”. MSMA does a very effective job on many unwanted grasses and sedges but it should be handled with care. Be sure to read and follow the label directions.
A newer active ingredient, quinclorac is becoming today’s preferred choice for crabgrass and other grassy weeds such as foxtail.
Permethrin? Pyrethrum? What’s the difference? Organic gardeners often use pyrethrum insecticides, which are derived from certain chrysanthemums. Pyrethrum breaks down quickly in the sun.
Permethrin is of the pyrethroid family that includes bifenthrin, deltamenthrin and others. It is a synthetic form of natural pyrethrum – however unlike pyrethrum it is more stable in sunlight, therefore it stays in the soil a bit longer. Permethrin is commonly used on humans and animals and can be found in a large number of products from head lice treatments to flea collars. A word of caution about permethrin – kittens and cats are sensitive to permethrin, so if you need flea and tick control for your favorite feline you should discuss your needs with the local veterinarian first. But if you need insect control in a garden or lawn, permethrin is a very good, broad-spectrum insecticide.
Imidacloprid, available in Merit and Grub No More, has a very low toxicity for humans and pets. It is highly selective and only targets certain insects. It does, however, control two rapidly-spreading and very destructive pests: the Japanese beetle and the emerald ash borer. Breakdown in the soil takes a few months and, since it is commonly used for grub and termite control, this is preferred. Imidacloprid can also be used to provide systemic season-long protection for trees and shrubs against a number of insects. When imidacloprid is used in lawns, care should be taken to control flowering weeds such as dandelions and clover as some studies suggest that this ingredient may harm bees.
Although the main compounds in fertilizers (nitrogen, phosphorus and potassium) are essential for healthy plant growth, it is sometimes difficult for a property owner to know what the soil needs. The best way to insure proper fertilizer use is to have your soil tested first to determine what nutrients are required. Then choose your fertilizer according to your needs. Take care to avoid fertilizer runoff in lakes and streams where it can raise nitrate levels.
Below are ten common errors people make when using pesticides and fertilizers.
- 1. Wrong time to apply
Post-emergent herbicides need to be applied when weeds are young and actively growing. This can be spring, fall or the coolest part of summer, a day or two after a rain is best.
- 2. Too many applications
Herbicides can take several days to a few weeks to get complete results. Even though the plant is dying, there may not be any visible signs, so property owners may feel the application didn’t work and may spray again. Give any herbicide at least 3-4 weeks for full results, although many will work much faster.
- 3. Wrong tool for the job
Unfortunately, choosing the wrong product can cost someone an entire lawn, beloved trees or ornamental plantings. Make sure you do your homework and read the labels thoroughly. Don’t use a non-selective herbicide if you only want to kill broadleaf weeds and not grass. Avoid using “all-in-one” products unless you need to satisfy all those needs. On the flip side, if you have difficult to control weeds like violets and creeping charlie, make sure you choose an herbicide that will address those weeds adequately. When using insecticides, do not use in any area not specifically indicated on the label. Many manufacturers provide detailed websites and customer service help lines. Take advantage of those tools whenever possible.
- 4. Mixing your own home brews
I’m borrowing this one from the Texas Farm Bureau because it’s a great piece of advice. If products don’t have explicit tank mix instructions on the label, don’t combine them. Besides making a really big mess in your tank, you could damage your lawn. Some products go together, some do not.
- 5. Unlabeled or unclean tanks
Basically, clean, well-labeled tanks prevent accidental lawn damage. A little bit of glyphosate left over can accidentally turn your garden insecticide in to a plant killer. Separate sprayers should be used for your lawn and ornamentals to prevent accidental damage.
- 6. Not calibrating your sprayer
Take the time to know what volume your sprayer puts out and at what speed you should travel when you spray. This will help avoid putting down too much or too little of a pesticide or fertilizer. Use a calibration guide such as the ones on the PBI/Gordon website. For hand held sprayers, for tank sprayers.
- 7. Improper spreader settings
When spreading granular products, make sure you have checked your spreader and adjusted it to the proper setting. This will avoid getting halfway through the lawn and running out of product. You also want to be sure that you shut your spreader off at the end of a run so that you don’t double apply product and get a big green spot in one area of your grass. Finally, if you get granules on sidewalks, drives, curbs or in the street, sweep or blow the granules back on the grass to prevent pesticides from washing down into the drains and storm sewers.
- 8. If a little is good… A lot is NOT better
Please read the labels and follow the directions. Do not intentionally put out more than what the label indicates. In many cases you are only wasting the product because it is at its maximum efficiency at the labeled rate. Increasing the rate can actually reduce your control and usually causes plant damage. Adding more product than indicated on the label is against the law.
- 9. Improper watering
Many insecticides and fertilizers need to be watered in for best results but watering in the wrong amount or at the wrong time may make herbicides ineffective. Make sure you check the watering instructions on your particular label and follow the directions for best results.
- 10. Using products in combination when you didn’t mean to
You grabbed a bag of fertilizer and then you sprayed your yard for weeds and insects – not realizing that the granules already had herbicide on them. This is a classic over-application mistake. Again, please read and follow the label directions. Keeping track of your purchases and keeping them organized will help prevent any duplication of effort.
The best way to promote a better environment is to use what tools we have in the way they are intended. Do be a good neighbor and regardless of your method, be sure your property is clean and free from hazardous pests. If you have any questions about how to safely and effectively control weeds, insects or plant diseases, contact your local or county extension office for help.