"Juniper tip blight is caused by one or two fungal pathogens, Kabatina tip blight (Kabatina juniperi) and/or Phomopsis tip blight (Phomopsis juniperovora). Both pathogens commonly infect young first year shoots, but can occasionally infect older shoots and stems. Similar to other blight causing diseases, once an infection has begun, juniper tips will rapidly turn brown and die.
The best method for controlling juniper tip blight is through good cultural practices and sanitation. As soon as tip blight becomes evident, the diseased shoots should be pruned out and destroyed since the dead juniper tips can continue to produce spores for up to 2 years.
Cut several inches below the infection and disinfect pruners often using a 10% bleach solution, 70% alcohol solution or other commercially available product (Greenshield, OxiDate etc.). Sanitize equipment, at a minimum, between each plant.
Avoid pruning on a rainy, wet day, which might spread the disease."
Font:
www.tnstate.edu/extension/documents/Juniper_Tip_Blights.pdf