I have a veggie patch that is about 50 feet from a stand of sumac. The runners from the sumac have reached my veggie patch and is starting to invade, so what do you guys think would be the best solution for halting or atleast slowing them for this season? I think the best solution long term would be to move the garden, or to allow pigs to root out all of the sumac but it's too late for that this year since my garden is all planted. Any short term permaculture solutions?
I'd push my spade into the ground on the edge of the garden towards the sumac trees. Cut off the roots. If they're too deep for your spade, there's a much longer edging tool that must be 18 inches long. If like me you hit hardpan clay then you may need to make two passes. After loosening the soil on the first pass in may go deeper on the second pass.
I assume this isn't poison sumac since you mention letting pigs root it out. I'm a fan of sumac tea, so would enjoy having them around. That said, the least invasive means is probably to chop down and cut the root, then pull the entire sucker/runner out. If you don't feel like doing this every year, I can only think of two solutions. One is putting the effort to move your entire garden. The other is to create a solid barrier.
Sumac roots aren't very strong and aren't able to break up rocks or other solid barriers. I've heard of people sinking metal plates in their garden borders to stop them. I wonder if pouring a deep cement edging would work. Something that runs that entire side of the garden and keeps out the roots year after year. Bonus, it will stop some burrowing animals on that side as well.
Once you've run a spade down the edge of your garden you could repeat this some distance from the garden. You say the stand of trees is 50 feet from the garden. Run a line 25 feet from the garden. If you find roots you can't cut with your spade, dig those up enough to cut with an axe. I have a maul that has a sledge on one end and a rough edge on the other. It's not that sharp so it doesn't bother me to chop into roots and earth. I wouldn't do that with my axe or my "Chopper 2"
In my yard roots are seldom deep enough to not get cut with a spade. I've seen Wild Cherry go 4 feet into clay. The one was maybe 3 feet in diameter and it took me hours of digging with a John Deere 450 High Lift to dig it out. That's an exception, especially for Wild Cherries which are considered shallow rooted. But 25 feet from your sumac I'd guess you'll find mostly feeder roots which won't stand up to a spade with 150 or 200 pounds standing on it.
If you're determined to keep everything as it is, you might consider a woodchip trench to the depth of the sumac root zone, or a little deeper.
If you inoculated the woodchips with a fungal slurry and compost extract, or even just kept it damp all year round, it would act as a soil life bioreactor, enhancing the soil-building and plant-nurturing capabilities of your soil. You would likely need to dig it out every season or two to trim the invading sumac, but most, if not all, of those chips would likely be soil after a season. Rinse and repeat, and you not only have a root barrier and swale, if properly located, you also have a soil generator.
A human being should be able to change a diaper, plan an invasion, butcher a hog, conn a ship, design a building, write a sonnet, balance accounts, build a wall, set a bone, comfort the dying, take orders, give orders, cooperate, act alone, solve equations, analyze a new problem, pitch manure, program a computer, cook a tasty meal, fight efficiently, die gallantly. Specialization is for insects.
-Robert A. Heinlein
I realize your situation is different, as you have a functioning garden in the sumac danger zone, but in my yard, I simply mow over the sumac that pops up in the grass where I don't want full plants. It does come back, but since I'm cutting the lawn every ten days or so anyway, it's not a problem to just mow over the sprouts again.
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