See:
Maple (Acer spp.) - Leaf Scorch
Dogwood (Cornus spp.) - Anthracnose
Cause Leaf scorch and leaf roll result from stress. Drought, heat stress, overwatering, and construction damage are possible causes of both problems. Leaf scorch also can be caused by overfertilization. Similar symptoms can be caused by herbicide damage.
Symptoms. Leaf scorch is characterized by browning of the tips and margins of the leaves. Leaf roll is a puckering and upward rolling of the leaf along the midvein. The undersides of rolled leaves are often pinkish or purplish. Sun or heat related stress will occur primarily on the south side of plants.
Cultural control Prevention is the key as there is no remedial action that can be taken once leaves are scorched by the sun, but effects are not fatal and new leaves will eventually cover damaged ones.
- Avoid compacting soil, which inhibits water penetration into the soil and reduces drainage.
- Provide proper irrigation and fertilization for your plants, especially during dry weather.
- Try to prevent injury to the roots and trunk, especially during construction or soil excavation.
Chemical control Use before hot summer weather. Always follow pesticide label directions. Anti-transpirants or anti-desiccants are not recommended since they have not been shown to be effective at preventing heat or cold-induced desiccation of plants beyond their normal adaptations.
- Surround CF at 6.25 to 37.5 lb/A plus a surfactant. A dry white film will result on all treated plant parts. 4-hr reentry. O
Reference Wang, F., and Yamamoto, H. 2009. Transpiration surface reduction of Kousa Dogwood trees during serious water imbalance. Journal of Forestry Research 20:337-342.
Chalker-Scott, L. 2010. The myth of antitranspirants, pp. 183-189. In The Informed Gardener Blooms Again, University of Washington Press, Seattle, WA.