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My black swallow wort journey

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Hi everyone, 

As I gear up for another summer of battling black swallow wort, I thought I'd share what I've tried so far. Last year I was able to control isolated patches of swallow wort by using Round Up poison ivy killer (contains small amounts of triclopyr) by spraying each plant until dripping. I was using 8 ounces of the concentrate in my 1.33 gallon battery sprayer with a bit (maybe 2 oz, I didnt measure) of 80/20 surfactant from tractor supply. That works well for individual plants. 

Now, I'm back to tackling my giant monoculture. I obtained some used billboards and put them down mid May. I tried sailing grommets with 4 inch landscaping pins, but that didn't hold. I needed something heavier. I've moved to rocks and milk jugs, which I need more of. The billboards seem to be suppressing growth, but I think being that they're white, they're still letting too much light through. I'm going to get more and double up with two layers. The portions of the photos that show no growth is due to the billboard being blown into a tangle from last winter.20180519_173019.thumb.jpg.4cf3c9b4ecfd9c7e1485f7185d1f236b.jpg

I just wanted to share since I know many of us are struggling to get this terrible invader under control. 






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  • 8 months later...

I thought I'd update my progress from last fall. The billboards worked wonderfully, helping me to reduce the square footage of monoculture needing to be sprayed. I did spray some of the swallow wort with 2% Garlon 4 Ultra. I mixed 7.7 oz of Garlon 4 filling it to the 3 gallon mark with water. I did add two ounces of Duo Stick Select surfactant to the 3 gallons. I sprayed with a Solo backpack sprayer with a semi-fine droplet until the plant was dripping. The first photo is a progression of covered plants in the foreground, sprayed in the middle, and not sprayed at the top of the photo. The second photo is from under the black billboard on September 23rd (about 3.5 months of smothering). The third photo is my upgraded stakes. Typical landscape stakes were not strong enough. I had to upgrade to heavy duty metal tent stakes (https://www.amazon.com/IUME-Strength-Unbreakable-Inflexible-Gardening/dp/B07B3M6P5P) and plain grommets #4 from Sailmaker's Supply .


Under the billboard.jpg

Upgrade the stakes.jpg

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