How to deal with plants invading from parkland?

June 14, 2017 5:58 AM

We live next to some parkland, and we're being invaded by plants--native and non-native aggressive varieties. It's unlikely that the town will address the parkland (where would they stop?), so I'm looking for means to control the invaders. Any means accepted (e.g. Roundup), but my property has a lot of plantings id want to protect.

We've got bishop's weed/ground elder, Virginia creeper, Norway maple saplings (which I just pull out), wild garlic, and not near us, but out in parts of the park, Japanese knotweed and Asiatic bittersweet.

We pull out what we can, when we can, but there's always more.

Are there any longer-term solutions (e.g., gravel border zone, fencing/edging that goes a certain depth below grade), or faster killing methods (glycophosphate, hot water, vinegar, baking soda, fire!). So, it's not necessarily that we don't know how to get rid of today's weeds, but more that our weeds have a lot of reinforcements behind them whose tide we want to stem or slow significantly. I'm not ruling out some wildcatting weed control in the park, though in that case I'd want the least invasive methods. Thanks!

posted by Admiral Haddock to Home & Garden (3 answers total)

Yeah, glyphosate, boiling water, fire. Those are the best weed control methods. Don't use fire without proper training. You don't say where you live but would seem to be eastern USA, and these instructions on controlled burning of prairie will still be some what relevant.

Gravel and fences will not help you keep weeds out of your yard, though they may help you define the area you want to defend. Seeds can literally travel several kilometers, rhizomes are happy to forage out hundreds of meters before surfacing. Frequent mowing will generally keep non-grass weeds down.

In principle, you could stop rhizomatic spread by digging a deep narrow ditch along the entire boundary, but that's a lot of work, and still needs lots of maintenance. And you'd still have seed rain.

You can consider organizing a volunteer day for people to pull invasive exotic species out of the park, but you really shouldn't be killing natives in park land because you don't personally like them.

On this: We pull out what we can, when we can, but there's always more. Yes, this is what maintaining a small selection of species and keeping out all others is like. It always takes a lot of work, pretty much anywhere. It's against the natural order of things.

So here's another approach: If this were my yard, I'd probably ignore the garlic and creeper, and consider those groundcover. Mow high few times a year to keep the woody shrubs down. The bishop's weed is an actual threat to the native flora, so I'd focus my effort on that, via glyphosate and boiling water, applied liberally as needed.

Keep in mind virginia creeper is enjoyed by many. You can use it to make baskets and swings an awnings etc. It has a handful of medicinal uses too. It's a nice plant, and is often intentionally planted as a ground cover and erosion control.
Wild garlic is prized by many as delicious food. Consider harvesting a bunch then giving it away to neighbors. Bishop's weed is edible too. You can eat the young leaves in salad, or pickle them when they get older. This site has lots of good info on edible weeds.
posted by SaltySalticid at 8:48 AM on June 14, 2017 [5 favorites]

I fight a personal battle against Virginia Creeper. I take a squeeze bottle of weed killer and hit the offending leaves every couple weeks. I don't try to eradicate it all at once, just keep up the pressure so the problem gets less over time. It's helpful that the plant I prefer, pachysandra, is not much bothered if I kill a few leaves with overspray.
posted by SemiSalt at 9:43 AM on June 14, 2017

Maybe bamboo barriers will be helpful for any encroachment by roots.
posted by ShooBoo at 10:40 AM on June 14, 2017