How do you rate the risks vs. benefits of mulching with uncomposted or raw wood chips?
Because mulching with raw wood chips (and several other materials) is such a common practice, it is difficult to consider that it might be bad. Disease effects notwithstanding, mulch provides valuable benefits, including moisture retention, weed suppression, and erosion control. Eventually, mulch decomposes to add nutrients, organic matter, and microorganisms to the soil. Research and demonstration projects in California, Florida, Illinois, New Jersey, Ohio and elsewhere have shown positive benefits from raw yard trimmings used as mulch or incorporated directly into the soil (usually with added nitrogen). These projects cover orchard, nursery, vegetable, and forage crops. For instance, avocado trees mulched for several years with freshly chipped yard trimmings have even shown less disease, compared to trees grown without mulch. Nevertheless, several highly regarded plant pathologists strongly recommend against applying raw, uncomposted wood (or straw) as a mulch. Research conducted at
