Each country in the European Union has its own definition of a forest and the European Commission has defined forestland as having at least 20% canopy closure (10% in the Mediterranean forests) and a minimum area of 0.5 ha. (1 ha. = 0.01 kmÂ²). Elsewhere, the definition of a tree can vary.
Lunula: the crescent-shaped area at the base of the human fingernail.
Humulus lupulus. Humulus lupulus is a species of flowering plant in the Cannabaceae family, native to Europe, western Asia and North America. It is a dioecious, perennial, herbaceous climbing plant which sends up new shoots in early spring and dies back to a cold-hardy rhizome in autumn.