There are over 100 species of the genus Pinus world wide, of which 36 are native to the United States.
Pines grow best in full sun on well-drained, acid soil.
Symptoms consist of purplish spots at the site of stem infection. Stems begin to swell four to six months after infection, resulting in spindle-shaped galls. Dieback of small stems or cankers on larger stems often occur. Galls slowly enlarge each year. During the spring blister-like fruiting bodies break through the pine bark releasing yellow spores, which are spread by wind and infect the leaves of oaks, the alternate host.