Goat’s Head Must Die

Our war with with invasive weeds remains a noble one

By Rob Breeding

My household is at war. Last fall we discovered a bumper crop of goat’s head weeds lurking under tall grass in the backyard of the home my buddy recently purchased. The discovery came the hard way, when we stepped barefoot on spiked seed pods we’d inadvertently tracked into the house.

Goat’s head seed pods are a bit larger than BBs, and spiked like a morning star, which is a particularly nasty medieval weapon. Imagine a sledge hammer armed with long, sharp spikes. The pods cure hard in the fall, and when you walk on them, the spikes jam into the soles of your footwear and you track them everywhere.

It’s a rather ingenious method of reproduction. The nasty little plants, also known as puncture vine, spread quickly if an infestation is ignored.

Apparently, that was the approach of the former homeowners, who must not have enjoyed frolicking barefoot in the yard. This spring we cleared grass from the infested flower bed, then implemented a multi-pronged attack.

Round one involved a generous application of a herbicide named after a small Montana ranching community north of Billings. Like many folks, I’m not thrilled with the use of herbicides around the house, but I’m also not a chemophobe. There are thousands of land mines in the backyard, any one of which could render my bird dog Doll lame if she puts a foot wrong.

We had to act.

We soon learned that initial Roundup assault wouldn’t be enough. The young plants mostly withered and died, but it rained, then warmed up, and hundreds of new goat’s head sprouts emerged. That’s when I decided it was time to get a better look. With careful hand and knee placement, I leaned close to the bed.

What I’d thought was soil was actually a layer of duff made up mostly of thorny pods. We could pour Roundup on that bed from here to eternity and not make a dent in future weed crops.

The next step involved hardware and flames. Fun! We took a weed torch to the flowerbed, wiping out all those baby goat’s head plants, and burning a fair share of seeds in the duff.

Our battle is far from over, however. The next time it rains I expect another wave of green out in the flowerbed. We’re considering more chemicals, another round of burning, and possibly covering the bed with black plastic to stifle future goat’s head growth. We may have to utilize all three, implemented over another summer or two, to finally gain the upper hand.

There are a variety of weeds with similar seed pods referred to as goat’s head. The one we’re fighting, a low-growing, vine-like plant with opposed green leaves and tiny yellow flowers, made its way to the West from southern Europe and central Asia. That part of the world seems to be a hotbed for particularly noxious weeds. When I first moved to Montana to live in the Bitterroot I admired the hillsides, which were blanketed with lovely purple flowers. I soon learned the purple flowers bloomed on spotted knapweed, one of a number of invasive Eurasian weeds taking over the valley.

That was back in the early 1990s, and many folks feared the spread of invasive weeds would eventually crowd out native plants and reduce the land’s carrying capacity for wildlife and cattle. Fortunately, those fears haven’t been fully realized. Elk numbers in the Bitterroot are near record levels despite the spread of weeds and the reintroduction of wolves.

Which isn’t to say we ought not worry about invasive weeds. Knapweed didn’t turn the Bitterroot into a wasteland, and goat’s head hasn’t yet done the same in our backyard, but those Eurasian invaders harbor the potential for evil deeds. Our war with them remains a noble one.