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You can look, but you better not touch

2021 07 31 hawke poison.ivyBy David Hawke -- One of the telling characteristics of an active outdoors person is their ability to cope with, or not, poison ivy. Yep, by the start of summer there are usually a great number of weekend warriors, ardent birders, dirt-under-the-fingernails gardeners and sundry other woodsy types that are scratching and suffering due to this most interesting plant.

          Poison ivy has always been a bane of mine although some people “never get it” (oh, how I envy them). My first case manifested itself when I was about 10, as my family was visiting the great CNE in Toronto. Fresh from a weekend camping experience, Dad and Mom took us to see the other side of life: a visit to Toronto (even in 1965 the “big smoke” was a world apart from quaint little ol’ Orillia).

          After a few hours of walking the midway, my right foot was crazy itchy and when the shoe and sock were removed a massive cluster of hard clear blisters was found around all my toes. Poison ivy! How cruel that nature had waited until I was surrounded by the height of artificial entertainment before revealing such a hard fact about nature and “care free” camping. So began my battles with PI.

          There are several growth forms in which this plant may appear, most common being an ankle-high version of three leaves hidden amongst the grasses. However, it can easily be found as knee-high foliage growing thickly in sunny, sandy areas; and, currently spreading northwards from the southern parts of Ontario, it can also be vine-like, climbing tree trunks to better swipe at passing hikers (I recently found a good colony of climbing poison ivy along the Black River Road).

Whether robust or thinly scattered, the tell-tale identifier is the stalked centre leaflet; other three-leaved plants have either no stalks or all three leaflets are stalked. On poison ivy the two side leaflets are close to the stem (officially called a petiole).

          The leaves themselves are quite variable, ranging from smooth edged to quite lobed, almost oak-like in shape. Note that the true poison oak is found far away from here, on the west side of the Rocky Mountains. There are plants growing locally that sure look like oak leaves, but are really just our friend PI trying to disguise itself.

The grief-causing oil (called urushiol) is found within the sap, and the sap of course is found in the leaves, stems, roots, flowers and fruit. Knowing this does little to ease your mind when you are wading knee-deep through a huge patch of poison ivy. Apparently, so I am told, you are supposed to wash your clothes, including your boots, immediately after coming in contact with this robust little plant. Don't use alcohol wipes as that just spreads the oil… stick with good old water and soap.

Note that the oil-laced sap has to penetrate the skin's surface and bind with protein before dermatitis (that would be “skin rash” for us plain spoken folks) can set in. This takes about 10 to 15 minutes to happen and once set, it cannot be washed off. I guess that shoots a hole in my definition of "immediately after," which seems to contain the passing of at least several hours and perhaps a sunset and a sunrise.

Depending on your skin texture and pH, the area of infliction and your susceptibility, the rash may continue to appear in new places over several days. This usually is attributed to the initial contamination, not the spreading of the original blister.

My last batch of rashes started to appear on my right hand, then my forehead, followed by the left hand, then small spots on my legs around the knees. This makes sense as my right hand was in the dirt with the roots, I then took off my sunglasses to wipe my brow and smeared the oil on my temple, all the while kneeling on the ground with my thin pants. Which reminds me, I should wash those pants before wearing them again.

The blisters are hard, hot and filled with fluid, so filled that the skin is being pulled apart in layers. Ouch. And herein lies a very good tip about treating poison ivy rash: do not break and drain the blisters, even with a sterilized pin; this creates a wound and the last thing your skin needs to deal with right now is a wound, it’s plenty busy already fighting off the effects of urushiol.

The rash itself is not transferrable, only the urushiol from the plant can create new blisters. Therefore, I’m not contagious and doesn’t that make you feel better already?

Cures to the rash range widely from “medically proven” (hydrocortisone) to “you gotta be kidding” (crushed leaves of jewelweed). However, realize that you are not actually curing the rash, just limiting the itchiness to a tolerable level. You are into this for two weeks, so tough it out.

So, what’s the best way to relieve the rash? Javex, gasoline or turpentine have been tried by desperate people (and yes, there have been times when I was considered a desperate person) and those methods DO NOT WORK. Best bet is time, tolerance and a conversation with the pharmacist or doctor. The very best way of beating poison ivy is simply wash up properly immediately after contact… oh, if only I could follow my own sage advice.

          And now some more news to make you hate climate change: poison ivy has proven to respond well to high levels of carbon dioxide in the air! Like all green plants that perform photosynthesis, poison ivy requires the carbon from the air and then releases the oxygen back out again. The carbon stays inside the plant as it grows and will be released when the plant dies and rots, just like it's supposed to do.

          But… what if the plants were to have extra carbon dioxide available to it, as well as stronger sunlight and warmer and more humid air? Scientists at Duke University in North Carolina were the first to release the bad news… climate change is like putting poison ivy on steroids! It grows faster, stronger, higher and has a more allergenic form of the urushiol oil.

          As with all things natural, everything is related to everything else. Driving a low-emission car will slow the growth of poison ivy. Who knew? Just a thought.

So, remember, "leaves of three -- let it be" and you will easily avoid trilliums and wild strawberries, and possibly a few poison ivy plants. You should learn to recognize this plant in all four seasons, as it can be quite a plentiful nuisance around cottages, farms, trails and beaches.

Dave’s Notebook: Hello on a chilly summer's morn. Not quite frost but definitely sweater weather! Cool fronts like this encourage the long distant migrators, like shorebirds, to start gathering for southern flights; Argentina is a long way off so they usually start leaving in August.

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© 2021 David J. Hawke

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