Proper identification of poison ivy (Rhus radicans) is essential for outdoorsy types if they wish to avoid coming down with the itchy rash that it causes. Elsewhere I have assembled poison ivy pictures as a visual aid for your identification work; it certainly makes sense to consult those pictures first, so that you'll have a good idea of what this weed looks like before you even come close to it! But thanks to a product named, "Ivy Alert," it is no longer necessary to rely on pictures alone.
Identification of Poison Ivy: Science to the Rescue
The Ivy Alert product comes in the form of a kit (small enough to carry in a large pocket). The key component of the kit is a sensing patch that detects urushiol, the oil in Rhus radicans responsible for the rash. According to the makers of Ivy Alert, the product generates "a color change to black in response to physical contact with urushiol. This color change is the result of a simple, reliable chemical reaction between the urushiol and the product's reagents and solutions." So instead of relying on eyesight alone, a chemical reaction helps you with the identification of poison ivy!
Now I'm no chemist, myself, so let's break down, as simply as possible, how this product is used.
Identification of Poison Ivy With Sensing Patches
- The sensing patches are sticky on one side; you get 15 of them in the kit, and you peel them off a cardboard backing.
- The product's directions show a patch being applied to a shoe; but for purposes of the identification of poison ivy, you could apply a patch to just about any object (not your skin, though!).
- Also in the kit is a little bottle of "surfactant solution," plus some swabs. Sprinkle some of the solution on the sensing patch you're trying out, to activate it.
- After you suspect the sensing patch has made physical contact with Rhus radicans, it's time to put your suspicions to the test. Apply a drop of the solution to a swab, and rub the swab on the test patch.
- If you then observe the formation of a black residue on the patch and/or on the swab, it means that you have, indeed, encountered urushiol. Immediately wash any skin area that you may have inadvertently brought into contact with the weed (directly or indirectly), as well as tainted shoes, clothing, garden tools, etc. (they can harbor urushiol).
Identification of Poison Ivy: Is It Foolproof With the Patch?
In a word, no. Just because your patch doesn't "test positive," that doesn't mean you haven't come into contact with Rhus radicans. Neither I nor the manufacturer is advising you to start rolling around carefree in a weedy area, just because your test didn't show traces of urushiol!
For my own tests, I applied the patch not to my shoe, but to a long pole -- I'm no fool! For those curious about the product's effectiveness for the identification of poison ivy, this is how I recommend you use Ivy Alert. There's no sense in taking unnecessary chances, so keep your distance from those weeds!
In my own first attempt at the identification of poison ivy through this product, the patch failed me: I knew the weed in question was Rhus radicans, but I did not achieve a positive test result. So I tried it again. This time, I applied more surfactant solution to the patch than the directions call for; I also rubbed the patch more vigorously against the weed. The result: a positive test!
Identification of Poison Ivy With the Patch: Bottom Line
The Ivy Alert patch is marketed as a product that you can wear on your shoe, for instance, to alert yourself to "unexpected exposure" to urushiol. Upon receiving a positive test, you would rush inside immediately to wash off any urushiol that may have landed on your skin. And, in fact, many folks may wish to use the product in just this way.
However, I'm more interested in another angle: namely, that the product could also be useful as a learning tool for novices in the identification of poison ivy. If you haven't already, obtain a basic idea of what the weed looks like through my pictures, then test out your newly found knowledge using Ivy Alert. Thereafter, with your eye schooled in what Rhus radicans looks like, you should be able to avoid it -- as long as you stay alert.
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