woodland invasives/restoration/elimination

5 years ago

last modified: 5 years ago

Hi. We bought a house with woodlands that had been neglected and overgrown with invasives. It's like an invasive horror movie: buckthorn, bittersweet, garlic mustard, dame's rocket. My number one target right now is the super invasive Herb Robert, stinky bob, geraniumrobertianum because it is invading spots of the woods where natives now have a foothold (lots of ferns, some doll's eye baneberries, partridge berries, false Solomon's seal, etc).

(I still plan to go after the stands of garlic mustard, loosestrife, bittersweet, dame's rocket as they emerge but the woodland is my first priority since I feel I can save it. Also the garlic mustard I'll prob go after with chemicals whereas the geranium is still intermingled in some areas w good native plants.)

I have been pulling these stinky plants since last summer and have used these freak warm days to do some weeding. I have read that I should not plant natives till I get rid of the geranium--but also that it takes years to do so.

My idea is to get rid of as much geranium as I can, plant woodland grasses appropriate for the zone and ecosystem and keep after the geranium. I know these plants are allelopathic and that all of my plantings won't make it, but I figure even if I spent $100 on seeds and 100 clumps of woodland grasses come up and get a foothold that's cheaper than buying plants. I'm hoping the grasses can kind of choke out emerging geranium.

Any thoughts from anyone who has attempted woodland restoration?

THanks!!

* I am planting silky rye and some other A type germinating woodland grasses native to our area. :)

** I also planted some viburnums where I yanked/poisoned buckthorn. Most of the rest of the understory is chokeberry and native dogwood.

Featured Answer

Anon Ymous

5 years ago

I'm in the middle of a similar project in the PNW. Removal of invasives on about 2 acres followed by native replantings. The method and timing of all this took a bit of research with some assistance from state/county resources.

This is my basic approach:

1. Identify which invasives were "highest" priority for removal immediately and come up with a plan for when and how to remove them. I have a lot of invasives so I'm actually phasing this work out over several years and tackling my lowest priority invasives in later years. Garlic Mustard would probably be higher priority than the Herb Robert in your case. You would need to research what herbicide is most effective with Garlic Mustard and what time of year it should be applied. You might also need to research how to time herbicide application around rain or pollinator seasons (or even time of day if doing foliar spraying). Check if your county has a noxious weed specialist you can email - I found mine very helpful and they were able to confirm my plan made sense and point me to resources. The more I researched eradication of different invasives the more I realized how incorrect most of the advice is on herbicide use and control methods. And not every landscaping company would be an expert in every invasive either, especially if it's quite new in the area.

2. Get a list together of native plants that work well together and check if your county has a "Conservation District" plant sale. In my area they only let you pick them up once a year, which happens to be the time of year that they can be most successfully replanted (around the rainy season).

3. Monitor regrowth in following years and manually pull or spot treat.

Thanks for restoring your woodland!

Sort by:Oldest

Comments (6)

PRO
beesneeds
5 years ago
How much area are you working with?
gardengal48 (PNW Z8/9)
5 years ago
Geranium robertianum is considered to have a circumpolar distribution. So certainly could be considered a native, At any rate, it was introduced to this continent so long ago and has naturalized so thoroughly it is now just considered by most authorities as a native wildflower or weed.

It grows rampantly in my area virtually year round. It appears anywhere - planting beds, the lawn, gravel driveways, etc. It is also throughout the surrounding native greenbelt. I would say any allelopathic tendencies are slight - it does not appear to have ANY impact on either native species in the greenbelt or in a cultivated setting.

I just pull it out when I encounter it, usually doing an early spring sweep to get rid of any that overwinters before they flower and set seed. Has a very shallow, fibrous root system so easy to pull. But then I haven't attempted eradication from a large wooded area. Maybe an herbicide is advised :-)
Related Professionals
Elkton Landscape Architects & Landscape Designers · Webster Landscape Architects & Landscape Designers · Baton Rouge Landscape Contractors · Green Bay Landscape Contractors · Mobile Landscape Architects & Landscape Designers · Madison Landscape Architects & Landscape Designers · Wausau Landscape Architects & Landscape Designers · Bend Landscape Architects & Landscape Designers · Kenosha Landscape Contractors · San Jose Landscape Contractors · Leamington Landscape Contractors · Tallahassee Accessory Dwelling Units · Colorado Springs Accessory Dwelling Units · Eau Claire Architects & Building Designers · Odessa Architects & Building Designers
Meghan (southern VT, 5b)
Original Author
5 years ago
last modified: 5 years ago
Thanks for your thoughts.

I have read that it is widely distributed, but it is considered problematic. I am not an expert in allelopathy by any means but it definitely chokes out everything around it in my woods and is known to create monocultures in woodlands. Where it has taken a hold there are no ferns.

But yes, it is easy to pull especially when the ground is moist. I'm hoping that if I can get enough of it out my seeds will stand a fighting chance. :)

Just fyi for anyone else who comes across this in a search:

From Oregon.gov: Weedy geranium populations have expanded exponentially in the Pacific Northwest in the last twenty years. Today herb Robert is becoming one of the most common woodland invaders in Western Oregon. An annual weed with a high reproductive potential, it has barely begun to infest all potential acreage available to it. Regionally, the species has been dispersed mainly by human activities into many watersheds. Locally, it is spreading by water movement, wildlife, recreationalists, gardeners, and land disturbance activities. It can encroach up to 250 plants per meter square, pushing out native flora ...

https://www.kingcounty.gov/services/environment/animals-and-plants/noxious-weeds/weed-identification/herb-robert.aspx

Invasiveness Rank: 67 The invasiveness rank is calculated based on a species’ ecological impacts, biological attributes, distribution, and response to control measures. The ranks are scaled from 0 to 100, with 0 representing a plant that poses no threat to native ecosystems and 100 representing a plant that poses a major threat to native ecosystems. - Alaska
Meghan (southern VT, 5b)
Original Author
5 years ago
last modified: 5 years ago
I'm talking about maybe an acre? I can pull it, more wondering about the chances of my seedlings to take hold before I can deplete the seed store. Thanks!!
Jay 6a Chicago
5 years ago
I'm not really restoring a woodland, but I started a garden in a wooded area that had been mowed for years. Some of the species that I've planted are Elymus histrix, Scrophularia, Penstemon digitalis, Podophyllum peltatum, Laportea canadensis, Rudbeckia triloba, Goldenseal, Pilea pumila, Symphoricarpos orbiculatus, and Ribes missouriensis. The Bottlebrush grass has seeded around nicely.