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A lot of us are do-it-yourselfers, and prefer to try something ourselves before calling in an expert.

For most of horticulture, that’s a good thing.  Getting one’s hands in the soil, planting, weeding and watering – it’s not only enjoyable, it’s actually therapeutic. Horticultural therapy’s a recognized way to deal with many problems, both physical and psychological.

As long as we’re careful with gardening tools and chemicals, we’re generally safe. I try to avoid using the most potent pesticides unless I have no choice, and that’s rare. There’s only one way to work with chemicals, however, and that’s to make sure you’re applying the right compound on the right target at the right time.

Just because you can buy a product, even an organic product, at a nursery or a home store, don’t assume that it’s harmless to humans, or to the more delicate parts of your landscape. A product designed to control one kind of pest may also be harmful to plants or other creatures.

To save yourself, your pets, your landscape and your neighbors, take a few moments before spraying anything that claims it will kill. Use those few minutes to read the label on the container. I know, the typeface is microscopic, but that’s the only way the company can fit all the necessary information.

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Many of the chemicals we can obtain are pesticides, which can be herbicides, insecticides, fungicides or other products designed to get rid of pests. Herbicides are often called “weed killers”, which is an unfortunate choice. It can kill a desirable plant just as easily as a weed. Fungicides are often listed as “disease controllers”, because fungi cause most plant diseases.

Fortunately, most chemicals of any sort have a label that indicates how problematic the product is. I know, the type on labels can be ridiculously small and tough to read. Even so, it’s worth the effort, because the information can be a lifesaver.

The signal word on any container is a good guide. You may need to look closely to find it, but it will be one of three words – caution, warning or danger.  These indicates how much was needed to kill ½ of the test animals studied. You’ll see the words on the container.

Most products will have the signal word “Caution”. It appears on products that would require more than 500 parts per million to kill half of the test animals. That doesn’t make them completely harmless, though, and they can be moderately irritating to eyes and skin. Some horticultural chemicals are so common that we can forget they’re designed to kill something. If we’re careless, we can hurt ourselves. So exercise caution, even with these.

The next in order of toxicity are products with the word “Warning”.  These take between 50 and 500 parts per million to kill ½ the test animals. That’s alarming enough, but what may be a bigger problem is be the irritation they cause to eyes and skin. If it gets in your eyes, it may take up to 3 weeks for the irritation to heal. Relatively few products have this signal word, but pay attention.

Finally - the signal word “Danger’. Homeowner type products rarely have a danger signal word, but I was able to find it on a disease and insect controller at my local home store.  When you see “Danger”, you’re looking at something that can cause irreversible blindness or skin damage. Now, this word may also be accompanied by a skull and crossbones, if less than 50 parts per million, eaten or inhaled, killed half the test animals. I’m pretty sure this kind of chemical wouldn’t appear on the shelves anywhere you can buy residential products, but with or without the skull and crossbones, these chemicals are dangerous.

It’s really important to pay attention to the signal words, but the rest of the label has information on how you can protect your skin, pets and plants. It can also tell you where and when to apply the product safely. Even those apparently harmless products have labels you really should read. From insecticides to cleaning products, you can get some valuable guidance.                        

For KNPR’s Desert Bloom, this is Dr. Angela O’Callaghan of the University of Nevada Cooperative Extension.


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