Pine root fungus problems can cause severe injury and loss of trees in your home landscape. With a variety of fungal pathogens attacking the root systems of your pines, the best method of protection is to familiarize yourself with what to look for and what do if problems arise to keep your home garden healthy.
Damaged or weakened pines are more likely to experience and suffer from root fungus than healthy, vigorous trees. Grow pines in areas that provide full sunlight. Pines thrive in moist, well-drained soil, according to the Clemson University Extension. Avoid waterlogged soils as they create an ideal environment for fungal germination.
Littleleaf is one type of root fungus that affects pine trees, according to the Clemson University Extension. Caused by the fungus Phytophthora cinnamomi, littleleaf affects all parts of the pine tree. All species of pines are also affected by annosus root rot caused by the fungus Heterobasidion annosum, according to the NC State University Cooperative Extension Service. This fungal problem affects the entire tree, as well, through a slow or rapid process.
Littleleaf symptoms usually appear once the disease has progressed to a serious stage with a display of thinned, damaged foliage, according to the Clemson University Extension. Stunted foliage growth only allows needles to reach half of their potential length and the tree experiences early death. Annosus root rot first shows up on pines through a display of needles that turn a red hue, premature leaf drop that leaves sparse foliage on the tree, and the presence of fungal growths at the base of the tree. The roots decay into string formations and the tree may suddenly collapse or die, according to the NC State University Cooperative Extension Service.
Apply a layer of mulch to the soil surrounding your pine trees. Organic bark is always a beneficial addition as it mirrors nature's production with dropped needles and bark. Mulch is particularly helpful for pines susceptible to root fungus because it provides the moisture retention necessary to pines without a need for wet soil. Additionally, mulch prevents the growth of weeds that attract infestations of many pests that can damage a tree, leaving it vulnerable to root fungus. Make your mulch 2 to 3 inches deep, according to the Clemson University Extension.
For littleleaf root fungus on pines, chemical control is not an option as pines are too large for effective foliar pesticide applications, according to the Clemson University Extension. However, management is possible by selecting a less susceptible pine like loblolly. To heal your tree's cosmetic injury, apply nitrogen-rich fertilizer. For annosus root rot, apply dry granular borax to cuts during pruning to prevent invasion from fungi. Avoid planting highly susceptible species like loblolly and white pine, according to the NC State University Cooperative Extension Service. For both pine root fungus problems, sanitize pruning tools between each cut and from one pine tree to the next to prevent localized and widespread transfer of disease.