All cankers are diseases of stressed trees.
Several cankers cause the tree to bleed heavily, but others listed cause little if any sap to occur on the outer bark. All cause internal discoloration. Rainy wet weather helps in the spread of the diseases. See also "Sphaeropsis tip blight
" and "Cytospora canker of Spruce
". Damage from various insects may also cause symptoms very similar to fungal cankers.
Life cycles vary with the fungal pathogen.
Keep the pine growing well and minimize long-term stress factors on the plant. Prune out dead and dying limbs, water properly during droughts and feed in the fall when most deciduous trees are defoliating.