Posts Tagged herbicides for controlling invasive plants
A good friend of mine and her significant other recently purchased and moved into a lovely new home in an adjacent county. They invited me out earlier this week to help them understand what’s growing on their 3-acre patch of Piedmont. I confess, I was a bit envious.
Their home backs onto state park land that protects a scenic river. This land has been covered in Piedmont forest for probably about 100 years now. Most likely before that it was farms and forests, and the forests were certainly regularly logged. That’s pretty much the story of land use for all of the southeastern Piedmont.
Unlike my home, which is on an increasingly busy road (a country by-way when we first moved here), theirs is quite a ways from the nearest main thoroughfare, accessed via a maze of well-established roads filled with nothing but mostly older houses. Frequent speed bumps likely discourage any non-residents from using these roads.
The result? My friend’s new home environment is noticeably quieter than mine. And the vegetation growing on her land and the adjoining protected forest made me long for my childhood days, when all the forests around here looked like that one — mostly anyway.
Her home sits atop a Piedmont ridge. Steep slopes on two sides fall down toward intermittent drainage ways that feed the river below. Large white oaks dominate the landscape; this year’s crop of acorns littered the ground. Mixed among the oaks were tulip poplars, red maples, sweet gums, sourwoods, dogwoods, redbuds, elms, viburnums, and a few mature loblolly pines — in short, all the native species I expect in such an environment.
But in addition to this mix of obviously healthy native plants, what struck me most was what wasn’t there: invasive non-native plants. I only saw two species, and both are likely still controllable if my friends take aggressive action immediately: Japanese Stiltgrass, and Privet.
Just for comparison, in my five-acre yard, I’m fighting those two species and:
We started battling a new invader this year: Oriental Bittersweet. As is true of most of our most pernicious invaders, this non-native vine was planted in the southeastern US for the ornamental value of its abundant, colorful berries. Alas, these berries are beloved by birds. They have “deposited” the seeds all over our southeastern forests. I was horrified when I visited the North Carolina mountains a year or so ago and discovered this invasive vine was snarling vast acreages of once lovely mountain forest.
This evil vine established a beachhead on my property beneath a native dogwood adjacent to my busy road. This mature dogwood produces abundant crimson berries every autumn, and I am certain that birds dining on the dogwood berries excreted the Oriental Bittersweet seeds that took root beneath the tree. It disguised itself among a bed of poison ivy that I was ignoring, which is how it became well-established. Wonder Spouse sprayed it with herbicide last spring, which knocked it back considerably. But it’s still there, biding its time until I forget about it. But I am determined that this latest invader will not gain permanent residence on our land.
I’m also watching for what is likely the inevitable incursion of kudzu. It dominates the property directly across the street from me. It would have crossed the road to my land years ago if the state didn’t mow it off the road every growing season. I can feel it plotting its invasion, perhaps via the drainage pipes beneath the bridge on my road that permits access for the creek that adjoins our property.
I know I’m not the only Piedmont homeowner battling invasive non-native plants. My blog has recently been visited by a number of viewers searching for information on controlling invasive plants. I have reluctantly concluded that unless your invader is just establishing itself in your yard, trying to pull it up manually will not control it. Herbicides seem to be the only option that will work in most cases. In my yard, deer will nibble on English Ivy in the dead of winter, but they never touch the Japanese Stiltgrass. I’ve read that even goats — known for happily devouring ivy, kudzu, and most any other plant in their paths — will not eat Japanese Stiltgrass.
Japanese Stiltgrass is creeping up the slopes of my friend’s new yard, working its way up from the intermittent drainage way below. That’s its favorite mode of transportation — water, which is why my floodplain is so plagued by it. I’ve resisted herbicides for fear of what they will do to my abundant frogs and salamanders, and the few fish still inhabiting my creek. But the literature states that the key is to use herbicides that do not contain an ingredient called a surfactant, because this is what causes the poison to stick to wildlife and hurt it. This link suggests herbicides that will kill this grass and are supposed to be safe in wetlands.
Wonder Spouse and I are planning on trying this weapon against our increasing infestation of Japanese Stiltgrass. I felt better about trying this weapon after talking with the curator of the Habitat Gardens at the NC Botanical Garden. She told me that she’s using it in her yard to battle this invader. She said the secret is to apply the herbicide consistently for five years — the amount of time the seeds of this grass remain viable in the soil.
I hate using herbicides, but there is no way Wonder Spouse and I can manually remove the invaders fast enough to prevent their spread on my land. I’m going to encourage my friend to begin using them now to prevent her from having my kind of problems. Right now, her land — the property that afflicted me with temporary forest envy — is about 20 years behind mine in invasive plant incursions. It’s been protected by the large stretch of contiguous forest it adjoins and its distance from major roads. But they must remove all the privet hedges planted by the previous owner immediately. And they must start applying wetland-safe herbicides to their Japanese Stiltgrass now — before their yard starts looking like mine.
For those of you wondering why I am so passionate on this issue, I refer you to my previous posts on this topic here and here and here. I truly believe that this is a battle we cannot afford to lose, folks.