Weed Deeds: The Quest To Map River Invasives

Out here in Big Sky Country, it's not about 2-weight rods and casting to hot-dog sized brookies in streams no wider than your bathtub.

It's driftboats on rivers as wide as an interstate, but out here there aren't so many roads, either.

That's just part of what makes this place so great, and as Chris Fleck, an outfitter in Columbus, guides the day's occupants down the Yellowstone River, the water's washing away their worries.

"It's not always about how many fish you catch or how big the fish are," says Fleck. "It's about the total experience."

But we all know that small fish aren't the ones that stories are made of.

A rainbow trout that would test 2X tippet smashes an ant in an easy lie along the bank, and nobody casts to it.

Another mile downstream and nobody's made a single cast, in fact.

For that matter, nobody bothered bringing rods.

"Today we're not fishing, we're hunting," says Fleck.

But they don't have guns or bows aboard the boat either.

Armed only with a GPS, they're mapping weeds that threaten not just the landscape, but the streams that cut through it.

In another boat on the Yellowstone River is Kerry Fee, Executive Director of the Park County Environmental Council. He used to be the president of his Trout Unlimited chapter.

"Whenever I'm on the river, to tell you the truth, I'd rather be weed mapping than fishing," he says. "It's an easy day on the river. You've got your GPS in one hand and a beer in the other. You see a weed and push a button on your GPS."

And you're making a difference.

When we talk about invasive species, we're usually talking about the stuff that lives in the water.

These guys have recognized that what's happening up on the banks matters just as much as what's happening down in the streams.

In other words, plants are not just plants.

"Noxious weeds are a dominant species," says Fee. "They'll take over the good stuff. The stuff we do want growing. For Montana, it's really important because people rely on wheat and hay. In this area, it's a rural area, and if you have noxious weeds in your hay you can't feed it to your livestock. So it's very important to ranchers to have healthy fields. They want to sell a clean crop of hay – no knapweed or thistle in their product. It's the same with wheat. Can you imagine some noxious weed in your cereal?"

Point. But you might wonder – what's that got to do with fishing?

"Noxious weeds are a dominant plant – they can overtake streamside shade trees and bushes that help keep the river cool," explains Fee.

When rivers warm even a little bit during the low flows of summer, it can be doomsday for trout. It takes the right kinds of trees and bushes on the bank to provide cover for fish, too.

Once noxious weeds overtake a bank, especially knapweed, they shove out the grasses that have protected the banks for thousands of years. When the grass is gone, the bank erodes. That causes problems all the way down to spawning success, because the loose soil fills in spawning gravel and smothers fish eggs.

"Noxious weeds could be choking off the right kind of vegetation that provides ideal habitat for insects that are on the rivers or other types of things as well," points out Fleck.

For the trout guys, it's all about the bugs.

Whereas the battleground is the boat ramp for invaders like milfoil and zebra mussels, the river itself is the way noxious weeds spread.

"Maybe you get a high water year like last year," describes Fleck. "The river bank collapses and washes in the river. It carries a bunch of knapweed or thistle downstream and they re-establish. You have to eradicate them at the river's edge."

The first step in the fight is finding out where the weeds are so they can be eradicated or controlled, and anglers are giving their time to make the maps. 

So what's lost in setting down the fishing rod for a day to help with projects like these?

"Nothing," says Fleck. "It was fun and people who participated and felt a sense of accomplishment. You feel like you're doing something to help the river system."

"You're enjoying a day and hearing the river under the boat," says Fee. "You're going to see eagles and osprey, deer and ducks with their babies. Give it about an hour and you feel the tension run out from between your shoulders. It sweeps you away. That's why we have tourists coming to this part of Montana from all around the world. It's one of the treasures of the United States and the world. It does its thing to you."

The riparian weed mapping project is part of the good work that the people at the Invasive Species Action Network are doing. If you haven't already, take their Clean Angler Pledge.

"I do a lot of work for the Yellowstone – it's a love of mine," says Fee. "And when I look at it out of the corner of my eye, it says thanks."