Diplodia Tip Blight is caused by the fungus, Diplodia sapinea. Many exotic and native pines are affected by the disease. Austrian, Scotts and Mugo pines are, perhaps, the most susceptible but native red, Jack and other 2–3 needle pines are also affected.
SITE: https://treedoctor.msu.edu/sites/default/files/docs/Jan12_DiplodiaTipBlightRedux.pdf