During years of gardening and farming, I used wood chips only sparingly to mulch around the occasional shrub, not wanting to pay for them. Recently, however, I’ve become a proponent of wood chips and now use large quantities of them in numerous ways. Here are five reasons why you should use more wood chips on your farm this year.
1. Wood Chips Are a Potentially Free Resource
One of the open secrets in the small-farm community is that wood chips are free in endless abundance. The most reliable suppliers are tree removal companies and or your local utility, both of whom chip enormous quantities of trees and are almost always open to new places to dump them. In my experience, many companies are eager to unload several truckloads of chips throughout the season, so if you need only a small quantity of chips, it might take you a while longer to find a supplier.
2. Wood Chips Are Effective Mulch
Although there are numerous ways to use wood chips on your farm, their must common application is as mulch in garden walkways. I use approximately two to three inches of wood chips to mulch the walkways between my beds and have found that this depth suppresses weeds for an entire season. Although straw, hay and leaves are also popular mulches, I find that they tend to break down quickly and need to be reapplied before the end of the season.
3. Wood Chips Have Ecological Benefits
Beyond their effectiveness as a mulch, wood chips can also bring ecological benefits to your farm. Wood chips can foster the growth of mycorrhizal fungi, for instance, which can spread into the soil of neighboring beds. Some mycorrhizal fungi can form mutually beneficial relationships with crops, while others can help to improve the overall health of the soil ecosystem. Thanks in part to frequent tillage, most growing areas tend to have more bacterial than fungal life, so encouraging a greater fungal presence in the soil can be helpful.
4. They Can Help Manage Water
As an additional ecological benefit, wood chips can absorb more water than other commonly used mulches. This absorptive capacity can help to minimize the runoff through your walkways; runoff, over time, can erode the sides of your growing areas.
5. You Can Use Them Flexibly
Finally, perhaps the largest benefit of using wood chips on your farm is their flexibility to be used in a variety of ways, including as a substrate for mushroom cultivation, as a mulch around the base of trees or shrubs or as a cover to temporarily control erosion. Different kinds of wood chips are appropriate for each of these uses, however, so do some additional research to make sure you’re using the right type for the job.
Also, be aware of certain things before you start using wood chips on your farm. As many growers already know, because wood chips contain a large amount of carbon, a substantial amount of nitrogen is needed to break them down. That nitrogen is therefore unavailable to plants that might otherwise use it. For this reason I don’t recommend directly mulching your vegetable crops with wood chips or mixing wood chips into your growing area.
You should also take care to not source wood chips that have come from allelopathic trees, which contain compounds that inhibit the growth of neighboring plants. Wood chips from such trees can still release some allelopathic compounds, which can have an herbicidal effect in the soil. Black walnut is one common allelopathic species in the U.S., but do some research to see whether other types of allelopathic trees are grown in your area that might make it into wood chips.
Despite the need to be careful in their application, wood chips are a free resource that can be used in numerous ways and can provide substantial ecological benefits to your farm.
