See:
Arborvitae (Thuja occidentalis) - Tip Blight
Juniper (Juniperus spp.) - Twig Blight
Note It is not clear what disease is meant by the common name "twig blight". Earlier handbook sections pointed to Juniper twig blight, however, Diaporthe juniperivora (formerly Phomopsis juniperovora) has only been found a few times by the OSU Plant Clinic and was also called leaf blight. Other fungal diseases occasionally diagnosed as "leaf blight" included Alternaria and Didymascella thujina (also called Keithia blight). Some fungal diseases have been diagnosed as "tip blight" with the most prominent being Pestalotiopsis funereal but also Botrytis and Phyllosticta. Additional fungi rarely associated with "twig blight" include Mycosphaerella, Pestalotia, Phytophthora and Heterosporium.
Reference Horst, R.K. 2013. Westcott's Plant Disease Handbook, 8th ed. Netherlands: Springer Science+Business Media.