A Boatload Of Bad

Day 315: Since I had to be in Yelm anyway yesterday morning, I threw the 'yak on the top of the car with a mind to going out on Lake St. Clair to remove the small infestation of Jewelweed (Impatiens capensis) which I'd discovered growing on a floating log about a month ago. Little did I realize how the rest of the day was going to progress.

It only took a few minutes to remove eight plants from the log, the tallest of which was about 2', but as I proceeded close to shore en route to the Sundews, I spotted a mound of the nasty stuff about 10' on a side and 6' tall nestled among thick blackberries. There was no way I could access it from the boat, and someone approaching from the heavily wooded land would need to machete a path through the thorns to reach it. Sighing heavily, I realized that I have my work cut out for me for as long as I'm able to paddle unless the rules regarding development along this side of the lake are relaxed. Jewelweed is an aggressive invader. As long as one plant exists on the shore, it will continue to spread to other areas of the lake. Further on, I noted another heavy infestation, this one covering close to 1000 sq. ft. Again, I could not access it from the water.

As I made my way along the shore, I noticed more places where the weed occurred to lesser degrees. For the most part, it was in spots I couldn't reach, but there were a few exceptions. At the location shown above, I was able to get out of the 'yak and stood in thigh-deep water to pull over 100 plants from the log shown just beyond the bow of the kayak. I was wishing I'd remembered to bring a bag, because the plants were covered in ants, and as I continued on my journey, I kept picking ants off myself and the 'yak by the dozen.

I was heartened when a sweep up the far east side of the lake seemed to prove Jewelweed-free, but when I reached the north end of the lobe, I found more of it growing on a piece of dock which had broken free some years ago and was now a "raft" of sorts, similar to the original Sundew Island, free-floating and now lost somewhere among the tangle of weed and wood along the shore. It seemed the Jewelweed had found an enterprising means of transport, rafting to new locations to release its future generations. Not on my watch! I forced the kayak onto the wood-and-styrofoam structure and pulled every Jewelweed within reach. By the time I got back to the car, the bow of the 'yak was packed with roughly 10 pounds of Jewelweed, enough to fill a large garbage bag. Even so, those inaccessible groves of this persistent plant will continue to disperse seed. A catch-phrase comes to mind, as applicable in this scenario as in the one which birthed it: "Still she persisted." Yes, that will serve.

Tussilago Farfara

Day 212: Last summer, the invasive plant species Tussilago farfara was discovered at a roadside pullout in the Park. Several theories suggest how it got there; a seed brought in with a load of purportedly "weed-free" road gravel, carried on someone's car bumper or in a piece of mud stuck to the undercarriage, or simply borne on a summer zephyr in some prior year. It has a seed head which resembles that of the common dandelion, little parachutes just waiting to be lifted away to new homes. In any event, several of us who are skilled in plant identification were authorized to monitor the site and to remove it, all but one specimen which our Plant Ecologist wanted as a test subject for chemical control. I had marked the spot with a rock (my companions in Team Biota are now very familiar with "Crow rocks"), but one thing led to another, and before he could treat it, the snows came. I was given permission to remove the plant manually if the site cleared, but the snow persisted for the remainder of the winter. I figured my rock would have been moved by the plow, but day before yesterday, we stopped at the site to check. The rock was still in place, and right beside it, Tussilago was putting up new growth. I lifted it with the dandelion jigger I'd brought along for the express purpose of vegicide and delivered the corpse to Arnie with the phrase, "I have a present for you." I'm watching you, Tussilago.

Good And Evil

Day 270: In close-up, it's easy to see that these two plants are not the same species, but from a distance of six feet, you might simply think one was a colour variation of the other or a fading specimen. The similarity of the two allowed an invader to go unnoticed for a number of years until it had spread over an area encompassing approximately 600 square feet of Longmire Meadow. It was only through the curiosity of a Park colleague that its true nature came to light. Once we determined that it was not our native Self-heal (Prunella vulgaris ssp. lanceolata, left) and was in fact Carpet Bugle (Ajuga reptans, right), we began working on a plan to eradicate it.

Over the next ten days or so, I pulled together a team of volunteers who assaulted it in a manner not unlike the grid-by-grid excavation system used in archaeological digs, and on Wednesday when they left the site, about 75% of the weed was gone. Yesterday, Plant Ecologist Arnie Peterson took a break from his office duties to help me clear the remainder. A total of 50 man-hours went into the project, contributed by eleven "deveg" team members. Nine full-sized trash-can liner bags filled with Ajuga were taken away from the site.

Ajuga propagates both by seed and by stolon. The site will have to be monitored closely for the next several years to be sure that this invasive species doesn't regenerate and get a toe-hold again.