Any plot of land of at least 5 ares (500 m²) with forest species capable of reaching a height of 5 m or more when adult and where the space occupied by trees is at least 10% is considered to be a wooded area. When they are young stands covering less than 10%, they must include at least 500 crop trees or, in the case of widely space plantations, 300 planting shoots per hectare. These areas are broken down into woods and forests proper (50 ares and over) and copses (from 5 to 50 ares). The latter, with wooded hedges, roadside trees and scattered trees (isolated trees or copses of less than 5 ares) constitute wooded non-forest areas.
Poplars, the cultivation of which is closer to agricultural production, although classified separately, are part of the wooded area.
Source : service de la statistique et de la prospective (SSP), ministère chargé de l'agriculture (site : http://agreste.agriculture.gouv.fr)