On Sunday's GardenLine show, I cautioned that although you may think your lawn has more weeds than anyone else, you can't double, triple or quadruple your dose of broadleaf weed control. If you add that much herbicide, you'll likely cause inordinate yellowing or maybe even kill the grass.
That, coupled with a recommendation I made about using glyphosate-based herbicides like Roundup by Scotts as weed or grass killers, sparked a couple of nasty comments in my email. Two listeners jumped all over me with accusations of conspiring to help glyphosate maker Monsanto "poison the world" and "kill baby farm animals" with "chemically poisonous weed killers."
So I guess it's time to slide out my soap box and do a little historical pontificating on the subject, especially for those who have been swayed by blogs and online rants about how bad Roundup is for the environment. Or how evil Monsanto and Scotts are. All I ask is that you read everything here before you accuse me of being in bed with those two companies.
First, I believe Roundup may be the most successful, most widely used, and most profitable garden chemical ever. Millions nationwide use it every year to control weeds, and it has been thoroughly tested by government regulatory agencies and found to be safe when used as directed. BUT ... I repeat ... WHEN USED AS DIRECTED!
You don't always hear me recommend Roundup, because I also like several other glyphosate-based herbicides marketed by other companies. Hi-Yield Killzall, Bonide KleenUp and Martin's Eraser are examples. Still, many folks who consider themselves environmentalists revile Roundup and its equivalents.
One reason is that glyphosate manufacturer Monsanto is the worldwide leader in developing genetically modified crops such as corn, wheat, soybeans and alfalfa that can sprayed with Roundup without killing the crops. I, too, have a distaste for genetically modified crops, but not because I'm afraid we'll all become Soylent Green by eating them. I just think there's a real danger their engineered genes may wind up in other plants, creating superweeds that nothing will kill. And I'm also put off by stories of Monsanto trespassing on private property to search for Roundup Ready crops that farmers haven't paid for.
So how does Scotts figure into all this? Well, Monsanto has licensed Scotts to sell Roundup for home use in the U.S. Scotts doesn't market Roundup to farmers — Monsanto still supplies the farm industry, which sprays tons of the stuff over Roundup Ready fields. Some studies suggest that such widespread spraying can harm fish and amphibians, but label directions specifically warn against using Roundup near or on water with the statement, "Do not apply directly to water, to areas where surface water is present, or to intertidal areas below the high water mark." I think that's pretty clear.
I've also read online posts that claim Roundup causes miscarriages in farm animals. The charge goes pretty much like this: Cow has miscarriage. New microorganism found in field where cow has miscarriage. Field where miscarriage occurred was treated with Roundup. Conclusion: Roundup responsible for microorganism that caused miscarriage. I think that might be a little bit of a stretch.
Look, I'm not interested in defending Monsanto. My mission has been and always will be to comment and advise on anything that can help home gardeners. But do you really think that killing weeds and grass in the cracks of our driveways is poisoning the earth?
I also find laughable the notion that people are evil if they choose to use "chemicals" to control pests or weeds in a responsible manner. Organic fertilizers are chemicals too, you know. Just sayin'. I don't spray chemical controls on my landscape or gardens unless I absolutely have to. If you listen to GardenLine, you already know that I apply nothing but organic lawn foods where the kids and the animals play. (Sounds like a song in there somewhere.) But I also use all manner of herbicides to control weeds, grass and brush, following the label instructions precisely. And I always use surfactants because a herbicide mixed with the predominantly hard water we all enjoy in Southeast Texas will not stick to leaf surfaces and can cause phytotoxic burning to the grass below.
So, circling back to the original point above — if you think your weed or brush problem is so bad you have to add more herbicide than the label calls for, DON'T! Such misuse, over-use and abuse of chemicals can cause problems that could eventually lead to having them banned forever.
Here are the top 10 rules for herbicide use in southeast Texas.