Yes, I know it sounds crazy, but we have a lot of trees that need mulch around them so they thrive this summer. The mulch is a great example of function stacking (a permaculture term). Function stacking means to accomplish multiple functions with one element . The element in this case is the woodchips that we are putting around the trees.
After being in the ground for 3 weeks, the trees look like this
Bare soil is not desireable because
- erosion when there is no root structure and plants above ground to help keep the soil in place
- lack of roots and organic activity feeding the organisms in the soil and keep the soil robust
- encourages “weeds” and grasses that will colonize the bare soil and compete with the tree and will need to be mechanically removed
Mulch Materials
Which materials used for mulch are really driven by econonmics and availability. The most available materials that are local to the farm are:
a. hay – we have pulled hay from our fields and purchased from our neighbors. Hay is easily available in round bales in our local area. As the hay breaks down it adds nutrients to the soil while providing helping to regulate moisture under the soil. This is especially important in the summer. Moist soil is much easier for the tree roots to penetrate which allows for a faster growing and healthier tree. Hay has 2 downsides. One downside is that it composts fairly quickly (which addes nutrients and organic matter to the soil) and this quick composting means we have to reapply it sooner than woodchips. One thing to consider is that hay is easy to move and apply. Much easier than woodchips when it comes to moving and applying it. The other downside is that it has to be fairly thick (thickness of the applied layer) to create enough shade to suppress grass weeds and grass. We use hay around our garlic beds very successfully. We’ve also had good success using hay around young trees as a much
Important note: Many hay fields are sprayed with a broadleaf herbicide to suppress weeds. This chemical application is so common that many farmers don’t mention that these chemicals were sprayed on the hay. Before using any hay in your garden or around plants on your farm, triple check with the farmer managing the field that they sprayed no chemicals on the field. The broadleaf herbicides can be transferred to your garden or farm via the hay and kill your crops.
b. wood chips – Our wood chip piles is about 4 months old (i.e. the trees were chipped at a another location and brought to the farm). It takes a pile of unturned wood chips around a year to compost. This means that they woodchips we just put around the trees are not anywhere near fully composted. As the wood chips compost they will have effects on the soil. The first effect is that they will raise the ph and they will deplete nitrogen from the soil at the interface layer between the wood chips and the soil. Because our farm soil ph is fairly low the effect of the ph going up slightly isn’t a problem. The nitrogen depletion (as the chips compost) isn’t a big deal either because the tree roots are 6 inches to 2 feet from that depleted layer. However, it is important to consider these two items if you used wood chips in your garden. We use a lot of wood chips very successfully in our garden at home.
Most of the time your supply of wood chips is a local company cutting trees for homeowners or clearing power lines. I keep an eye out for arborists working in the area. When I see a tree cutting crew, I usually stop and let them know I would really like to take their chips on our farm. Often we can get them for free. In some locations, you can use www.chipdrop.com and get free wood chips. It is important to note that if you get compost from a municipal or county source that it can contain broadleaf herbicides from grass clippings (where homeowners spray their yards). So be very careful with the source of your compost.
The wood chips do a great job retaining moisture under the wood chips. Over time they will add nitrogen and organic matter to the soil. The composting process for wood chips takes a while so the wood chips we are applying now should stay in place throughout the summer. The wood chips also help suppress weeds and grasses that would otherwise compete with the tree as it is getting established. If you want to suppress weeds and grass with wood chips they need to be a minimum of 8 inches thick.
c. comfrey – when we plant a tree or bush we generally plant comfrey root cuttings as well. The comfrey grows through the hay or woodchips and acts a living mulch (helping regulate moisture at the base of the tree or bush) with also add orgranic matter in the fall when the plant dies back in the fall. We usually use comfrey as a companion to wood chips or hay. The comfrey does even more function stacking as a medicinal plant and as a root that we can dig up and sell as a starter plant to homesteads and other farms that want to establish comfrey on their farms.
Notes about comfrey – when you purchase comfrey you want to purchase sterile comfrey like the Bokcing #4 Russian comfrey. This of comfrey spreads underground and is very manageable. Varieties of comfrey that aren’t sterile can spread by seeds and become invasive on your property, showing up places that you don’t want it. It is also important to note that comfrey doesn’t thrive in some areas. It is a great plant but it just won’t do well in some areas. Another great source of comfrey cuttings is Perma Pastures Farm in WNC. All of our comfrey plants originally came from them in the form of cuttings that we planted.
Equipment Needed
We have a lot of trees to mulch, so the tractor is a game changer. In your garden, a hand cart is often a great solution.
Next Steps
We still have more trees to mulch, but we are about 1/2 way through. We also have trees I hope to cut this winter. So lots to do.
In March we hope to plant
– jujube trees
– quince trees
– pomegranete trees
– goumi berry bushes (nitrogen fixer)
Other planned activities
– cut trees shading the fruit trees in field #2
– extend the anti-deer fences in field #2 and the cushaw patch to accomodate the new fruit trees as a they grow and allow for room to mow around them
– mulch the latest trees
– put up a trellis for the goji berries we planted in November
– amend the soil in the garlic beds
– extend the water lines in the food forest and field 2 to allow first year irrigation of the fruit trees and bushes
Thanks for coming along the for the ride with us!