Animal And Plant Toxins

Substances to avoid!

Organisms, and we fall in that category, tend to have evolved biochemical methods to discourage efforts by other creatures to interact with or exploit them. Humans don’t have spines loaded with toxins, skin containing gastric irritants, or fangs dripping with neurotoxins. What we have are large brains and intermittent reasoning powers.

We tend to avoid plants with threatening spines, a wise decision! Many of those spines are a mild threat. Thicket-forming plants like roses and raspberries tend not to have poisoned thorns. Part of such plants’ reproductive strategy depends upon mobile creatures such as mammals or birds eating their tempting fruits and later pooping out seed-laden turds in new environments.

Other plant species just want you to stay away. They have evolved nasty deterrents, irritating or inflammatory chemicals which their thorns will convey into even the most minor skin puncture.

Here is an anecdotal example from my Missouri years. Honey locust (Gleditsia triacanthos) is an invasive thorny tree in the Midwest. The species will move in and occupy un-mowed areas, competing with Black Walnuts and Green Ash. Honey Locusts have dense wood which makes good firewood, but those thorns! After some years I made it a habit to double-girdle big Honey Locusts with a chain-saw when I was out cutting firewood. Three years later the bark and thorns would be gone and I’d cut them down and cut them up.

I had noticed that Honey Locust thorn punctures tended to get infected. The thorn-wounds took a long time to heal.

Once, when my kids were young, I hitched a wagon to the tractor and set off across a field to cut firewood in a bottomland area where I had girdled several Honey Locusts. Unbeknownst to me my six-year-old daughter Adrian had followed me. She was barefoot. While I was cutting rounds from a bare Honey Locust trunk I heard a shriek, followed by crying. I shut the saw off and saw Adrian limping towards me.

“Dad, I have a thorn in my foot!”

I looked at her foot and pulled a thorn from it, but the very tip of the thorn didn’t come out. I hoisted Adrian onto the tractor seat and headed for home with just a partial wagon-load of firewood.

Adrian’s thorn-injury became swollen and infected. We took her to a local doctor.

The gray-headed doctor examined Adrian’s foot. He said:

“Hmm… evidently there is still a bit of that thorn in there. It’s a bad infection, but, really, I hate to cut into a patient’s foot. Surgical cuts in the bottom of a foot are tricky to heal. I’d recommend that you just keep an eye on her foot. The infection will come to a head and burst. Look at the pus which comes out and I imagine you will find the tip of the thorn.”

We borrowed a crutch from a friend and poor little Adrian used it for a week or so. Her foot swelled, and one afternoon the infection had ripened, and it just burst. I did see the evil thorn-tip in the pus we cleaned up.

I’m glad that is too dry around here for Honey Locusts to grow! We have other thorny plants, though, all of which seem to have some sort of toxin coating their thorns. Agaves have wicked brown thorns on the tips of their succulent leaves. And then there are the insects! This time of year there are tiny gnats which are small enough to fly right through a screened window. The tiny bites take weeks to heal completely.

Out here in the valley I don’t see many scorpions, stinging creatures which are quite common in Bisbee. I encounter rattlesnakes now and again. They tend to give fair warning before they actually strike. I don’t provoke or shoot them.

The other night I opened the west window which is just above my bed. It was a warm night and I was hoping to catch a bit of the breeze from the mountains. I was appalled to see this:

I was amazed. Who or what had burst through my screen? My cat, some years ago, had enjoyed climbing on that screen in an effort to get my attention, but she now lingers around the front door if she wants in. It occurred to me that whatever had breached my screen security might be lurking under my bed! No wonder that I’d been getting an unusual number of inexplicable night-time insect bites! I need to fix that screen before I am bled dry…