Black pine trees are susceptible to a variety of fungus problems that cause damage as severe as significant cosmetic damage and death of plant parts. Familiarize yourself with different types of fungal infections that display greatly varying signals of infection. When you notice symptoms, know what to do for continued health of your home landscape trees.
Vigorous black pines are more likely to avoid disease problems and are more capable of fighting them off as opposed to stressed or injured trees. Grow black pines in locations that offer full sun exposure for optimal health and growth. Black pines thrive in well-drained, acid soil and have good tolerance to salt spray, reports the Clemson University Extension.
Cenangium canker is a fungus infection of black pine trees caused by the fungi Cenangium ferruginosum and C. atropurpureum, according to the Cornell University Plant Disease Diagnostic Clinic. This fungus usually affects shaded branches on the lower levels of the black pine tree. Another black pine fungus problem is brown spot, caused by the fungus Mycosphaerella dearnessii, according to the NC State University Cooperative Extension Service. This problem affects black pine foliage.
Cenangium canker on black pines result in benefits as well as damage. Needles become brown and often fall from the tree. However, the tree is benefited by fungal growth that kills lower branches considered "non-functional," according to the Cornell University Plant Disease Diagnostic Clinic. Additionally, it speeds the decomposition of fallen plant parts that return to the soil, bringing nutrients with them. However, the fruiting bodies that occur on lower plant surfaces are a sign of a tree that may experience diminished health if the tree is already in a poor state. Brown spot on black pines results in striped brown spots with yellow borders on needles that undergo complete discoloration from yellow to brown. The diseased needles typically drop early, sometimes contributing to severe defoliation, according to the University of Wisconsin Extension.
Natural control is the only available management method for cenangium canker, as there are no effective chemical controls. Remove and destroy affected plant parts. Sanitize pruning shears between each cut and from one black pine to the next as a means of preventing the transfer of fungus. For brown spot, plant disease-free black pines and only prune during dry conditions, advises the University of Wisconsin Extension.
While there are no chemical control methods available for cenangium canker, there are effective options for brown spot on black pines. Apply a chemical fungicide with the active ingredient chlorothalonil or Bordeaux mixture, says the University of Wisconsin Extension. Apply a fungicide when needles have reached half of their full growth potential and apply a second coat to your tree after three weeks if infection is extreme or in periods of excessively wet weather. For optimal results, saturate all foliage.