Last week I tweeted about a Canada Goose apparently eating smartweed in the Wetlands. I also mentioned that not many creatures will eat the pungent weed. Other then a few caterpillars, the Smartweed Caterpillar (Acronicta oblinita) and the Tobacco budworm (Heliothis virescens), I personally haven’t witnessed much in the way of smartweed consumption among our fauna (there seems to be a caterpillar adapted to eating just about every plant in existence).
There’s little doubt that many creatures use smartweed for cover, shelter or for a substrate on which to build upon (like a spider web).
But what is smartweed and why wouldn’t animals eat it? Smartweed is a plant that belongs to a group of plants in the genus Polygonum. There are many different kinds of smartweed, some grow in wet areas, some in drier habitats, but they all have one characteristic in common that gives them the collective name of smartweed, they all have an acrid, or peppery, taste to the leaves.
Some smartweeds are more peppery than others, if you eat the leaves of the hot ones it’ll make you “smart.” No, I don’t mean that it’ll make you more intelligent, or turn you into a smart aleck, if you aren’t already one. In this sense of the word “smart,” it means hurt, it’ll make your mouth smart, or hurt.
Being curious, I did a quick search on the internet “what eats smartweed,” and came up with a brief list of smartweed consumers. Here’s the list as compiled by the Fairfax County Public School System in Virginia:
Mallard, Canada Goose, Wood Duck, Northern Bobwhite, Wild Turkey, Red-winged Blackbird, Brown-headed Cowbird, Northern Cardinal, Dark-eyed Junco, sparrows, Mourning Dove, Eastern Chipmunk, and White-footed Mouse.
I don’t know how the Fairfax County Public School System came up with the animals on the list, whether by observation or simply copying the list from another source, but it sounds reasonable. Did you notice who was second on the list? That’s right, Canada Goose.
The animals in the above list eat the seeds though, not the leaves. White-tailed Deer, Eastern Cottontail, and Muskrat are said to eat the plant itself. I can see why the deer made that list. If deer can eat the milkweed in my yard they can eat anything, but of the rabbit and muskrat, I’m not entirely convinced.
We have smartweed growing in our Wetlands (goose photo above) and I’ve seen nothing other than the goose eating it, although the goose may be browsing on something beneath the water that I can’t see and not eating the smartweed at all.
Ranger Kristin and I planted about a dozen pickerelweed plants in amongst the smartweed in the Wetlands last winter (2011-2012). During the spring, I kept an eye on the pickerelweed as it grew larger each day. Just as its big, somewhat heart-shaped leaves opened, the plants began to dissappear. There was nothing but gnarled stems and a few leaf fragments left among the smartweed each morning as I inspected the plants. The smartweed, however, was left untouched.
The only creature that I can imagine eating the pickerel weed is a muskrat. Muskrats are more likely seen in wetlands with cattail. We don’t have cattail in our wetland. Over the years, though, during two separate springs, I noticed a few cattail volunteers sprouting up. Like the pickerelweed they too soon disappeared, only a few leaf fragments left behind as evidence that they had once occupied space in our wetland. They were most certainly done in by a muskrat.
I’ve seen muskrats in the Wetlands on occassion. But, they do most of their browsing in the dark, when all of we people are away doing other things. If the disappearance of the plants is not enough evidence of their presence then a glimpse of one every now and then is absolute proof. Why don’t I see evidence of them eating the smartweed?
I briefly entertained the thought that our Red Swamp Crayfish ate the pickerelweed, and maybe they did, but it looked to me from the fragments left behind that it was a muskrat what did ’em in. As much as I’d like to, I can’t blame this on the crayfish. I have seen the crayfish, who are known to eat just about anything, browsing on whatever was growing on the smartweed (like algae) but have never actually seen them cut into the plant itself. If they don’t eat it, it must be bad.
However, and this is a big however considering what you’ve just read about smartweed, if you do a search on the internet you will find recipes for human consumption of the plant. Depending on the variety of smartweed, you can use the leaves, roots and seeds for everything from seasoning for salads to purees. Personally, I like this particular use for at least one variety of smartweed as described in Edible Wild Plants: Eastern/Central North America from the Peterson Field Guides series, “The tiny bulblets, stripped from the flowerheads, make a pleasant nutty nibble.”
Greg Dodge is a professional naturalist as well as a writer, videographer and producer of natural history DVDs. His images have been used in various TV productions, museum displays, and corporate videos. Above all, he has a fascination and passion for all things natural.
He can be found Tuesday thru Saturday in Explore the Wild, Catch the Wind, or on the Dinosaur Trail. Ask him what’s new in the wild!