Mulching the landscape is a recommended practice to moderate soil temperature and moisture and prevent weeds. Wood chips created by tree trimming companies can be an inexpensive way to mulch around trees and shrubs in the landscape. Homeowners have some concerns about the effect green wood chips may have on their landscape plants.
Will using fresh wood chips as mulch deplete nitrogen from the soil? Microorganisms found in the soil break down organic matter using nitrogen from the soil. Wood chips are very low in nitrogen so more is pulled from the soil to break down the wood chips making the nitrogen less available for the desired plants. However, when used only on the surface as a mulch, this is not a concern. It is not recommended to incorporate fresh wood chips into the soil. Recognize the difference between mulch and compost.
Will wood chips from a diseased tree spread the disease into my landscape? The short answer is “it could.” However, if handled properly, the wood chips can be safely used in the landscape. If it is known that the wood chips are from a diseased tree, allow them time to dry out completely before spreading in the landscape. To be safe, avoid spreading the mulch around trees of the same species where the wood chips originated.
Will using wood chips near my home encourage termites? This can be a concern if the wood chips are mulched right up to the foundation of the house. Termites are light and heat sensitive and will not bother the chips themselves if they are 3 inches deep or less. Therefore, keep the depth of the mulch less than three-inches near the house and other buildings. Also, leave a bare area several inches wide next to the house so that any termite activity is noticeable.
Cynthia Domenghini, Extension Agent
