Monday, January 04, 2010

With Extreme Prejudice

Even a plant-lover, and I do consider myself such, can be challenged by some species, and the mellowest of us can be pressed into trophy hunting when circumstances are right. Summer is the season for bagging the biggest baddest trophies in our neck of the woods. Each year I've been going after my limit, but of course, you never run out of this bad boy. Its beauties, and I'll grant there are some, are only petal-deep.

The object of my disaffection and prejudice last season, as in years past, is Dalmatian Toadflax (variously Linaria dalmatica, Linaria genistifolia ssp. dalmatica, etc.) The experts say "don't pull it—it just makes it come back stronger," but that never made sense to me. So I started an experiment in my own neighborhood, ruthlessly attacking every sprig I could find while out walking around the block, especially after rain. Pulling weeds is so satisfying when the ground is wet, and you really feel like you're getting results! When it's dry, and stems snap off at ground level, you have to suspect your efforts are futile.

Hypothesis: Control of Dalmatian toadflax can be achieved by repeated, diligent hand-pulling.

Methods: Repeated diligent hand-pulling, wherever, whenever, but especially in the immediate home territory.

Goal: A reduction in the local population, or (at the least) a drastic decline in recruitment of new individuals by seed. If one can only keep them from flowering, that has to help, right?

Results: Bags of garbage, at least the inflorescences of which have to be treated like the hazardous waste they are, and the opportunity to have roadsides free of these yellow snapdragons! And, I truly believe, considerable success in knocking local populations back and preventing their expansion.

Thus the "bagging" of trophies is literal here, and like any good hunter, I felt compelled to document my success—so let's back out a little on the photo above for the traditional shot: June 16, 2009, selections from my daily limit. (No, I resisted the impulse to have my picture taken holding them by the roots...)

That this Eurasian species has taken over most of the United States is documented here, by the USDA Plants database. Grey color indicates its non-native status in the U.S.

In Colorado, I suspect it occurs in many more counties than shown here in the USDA map.

Posted for the current edition of Berry-Go-Round. More on this species and its control a bit later.


Ellen Rathbone said...

OH, NO! Another invasive!?!? Sheesh - it seems like half the plants I purchased for my assorted gardens have turned out to be invasive! You'd think nurseries would know better! I try to keep up with what is invasive and not plant it, but it seems to be a losing battle! I guess I have to yank out my toadflax now, too. >sigh<

Sally said...

Yes, that's the problem, the nurseries have had trouble getting the message. Even with purple loosestrife.

Maybe DT isn't as much of a problem in NYS-- in fact, I only see one county (check the USDA link)...

Michelle said...

..and purple loosestrife is soooo beautiful. I love the plant, I love the color. So, would fireweed be an acceptable substitute for these two invasives, toadflax and purple loosestrife?