Planning a Food Forest? Don't Go Scorched Earth!
I’ve recently been engaged in discussions with a couple of folks planning food forest systems… and there’s one question that keeps coming up.
“Should I clear out everything before I plant?”
If you’re planting into an existing forest, I’d argue that it’s almost easier than starting with a bare field.
“But how can that be, Davy G? All that chopping! All those horrible invasive weed trees! All the shade! Heavens… give me a lawn any day!”
I know. Starting with a bunch of huge oaks or towering poplars is daunting… but there are benefits to starting with an established and mature ecosystem.
“Like what? My chainsaw budget is already outrageous… and all I’ve done is carve a manatee mailbox with it!”
Yes, yes… I’m getting to it. Stop interrupting!
A forest is more than trees. It’s a huge web of interactions. Birds, mammals, reptiles and insects fill a healthy piece of woodland… and things are even more complicated beneath the surface. In the trees’ “rhizosphere,” i.e., where the roots live, there’s an amazing diversity of microscopic activity going on. The complexity of a forest microecology is far beyond that of a simple lawn… and you’re going to want to keep those interactions going for optimum success in your project.
Here are a few tips.
1. Make The Pests Work For YouIf you have fast-growing foliage, dense thickets or invasive species on your plot, you can often use many of them to your advantage. Let’s take a look at one common example. One of the trees of the southeast that I get plenty of complaints about is this deceptively beautiful invasive:
That’s a mimosa tree, also called a silk tree, known properly as Albizia julibrissin. It often grows in disturbed areas along roadsides, as an understory tree on forest edges, and right in the middle of your landscaping where you don’t want it. The tree is a prolific seeder and grows very rapidly. It will come back from the ground if you chop it down so killing it can be tough.
That said… why kill it? Unless you’re a native plant purist and can’t stand to have your property defiled by an invader, there are some great uses for this tree.
First of all, it’s a nitrogen-fixer. If you plant a fruit tree next to a mimosa tree, then chop the mimosa branches as they reach above the fruit tree, your fruit tree will do better than if it was planted alone. Every time you cut back a nitrogen-fixing tree, nitrogen is released as the root mass declines in response to the loss of canopy.
Secondly, you can use the chopped branches as mulch around the base of your fruit tree… which leads me to my next point.
2. Harvest the Biomass
If you have a forest, you have a lot of resources. One mistake I see people making all the time: they cut down trees and shrubs, then burn them to clear the ground.
Don’t do that! You’re literally sending your soil fertility up in smoke. If you plant wanted species, then chop and drop the unwanted species to feed them, you’re saving on mulch and soil amendments as well as feeding the all-important soil microecology.
At this point, I must confess: when I first bought my current property, I needed to clear some oaks to make way for my garden. Once they were felled, I was overwhelmed with the amount of debris so I burned it. The next year, I really got into the idea of hugelkultur beds and feeding rotten wood to my food forest.
I kicked myself over that one.
BUT – it’s never too late to repent. Even if you simply set aside logs and let them gracefully rot away into the ground, you’ll be adding greatly to the soil beneath.