Sean O'Brien, from the UNH Cooperative Extension, takes a look at how beech leaf disease spreads and the signs to help you ...

Depending on the efficiency of the plant or tree species, it may take as little as 200 pounds (24 gallons) of water to 1,000 pounds (120 gallons) to make a pound of dry matter.

All tree leaves have an outer layer called the epidermis, which can also be used in the identification process. This leaf "skin" always has a waxy cover called the cuticle and varies in thickness.