What do you usually find on the roadside? Sand, bottle shards, broken-up pavement, maybe the flattened remains of a porcupine or a Big Mac. Life is hard on the margin, which is why I've admired these striped tan stalks that sprout up every spring on the Oak Point Road here in Maine. Yesterday I decided these sturdy stems deserved more respect. I decided to figure out what they were.
I first tried a Google search, but I didn't know what key words to use. I typed in TAN STALK THIN and, bizarrely enough, got as one of the first results, "Left-hand-assisted laparoscopic resection of hepatocellular carcinoma in an accessory liver." Whoa! Welcome to the wired age! Now I had to do a separate search to find out what an accessory liver was. (An unnecessary lobe that grows off the liver in very rare cases, as far as I can tell. Apparently, if you want to impress the medical crowd at a cocktail party, just boast, "I can resect one of those babies lefthanded!")
I tried more searching. I typed in TAN STALK ROADSIDE and the first result, inexplicably, was the website for the Wellsboro (Pa.) Area Chamber of Commerce. (Turns out Wellsboro—who knew?—is home to the so-called "Pennsylvania Grand Canyon," otherwise known as Pine Creek Gorge.) I tried again. TAN PLANT ROADSIDE took me to a Chinese research paper entitled, "Bioaccumulation and physiological effects of excess lead in a roadside pioneer species Sonchus oleraceus L." (When I looked up Sonchus oleraceus L., it was a yellow-flowered herb called common sowthistle. )
Then I remembered Tom Vining, a plant expert who lives on Mount Desert Island. I e-mailed him a photo of the tan stalk and he quickly got back to me with the news that it was field horsetail. Because its stem contains silica—essentially, sand; no wonder it thrives on roadsides!—field horsetail used to be used to scour pans. It also was made into a diuretic tea, a cough medicine for horses and a clothing dye. Perhaps most amazing, a subsequent Google search revealed that it "can accumulate gold in its tissues, up to 4.5 ounces of gold per ton of fresh plant material." At the current price of more than $1,140 an ounce, that's five grand per ton. Proof again that money doesn't grow on trees—it grows in little tan horsetail stalks.
Bet you look more closely at the plant life the next time you're walking down the road.