Canopy (biology)

A screen is in forestry means all the crowns of the trees of the upper strata of the forest, over the subsequent generation portfolio or crop plants (eg blueberries).

Importance and peculiarities

Its importance acquired the screen by the shading of the vegetation growing underneath. He creates a forest indoor climate in a given area, which provides in comparison to free land for a moderate course of humidity, temperature and sunlight. The reduced light supply for the growing plants under the screen means that this tends to drive out later in the spring, so that their risk is reduced by late frost.

The cultivation of some tree species in Europe is for this reason often only " under the auspices " possible. Especially in the German-speaking part of complex silvicultural systems have been developed during the regeneration processes of the vulnerability of young trees against late frosts into account ( shelterwood in its different variations). At risk from late frosts are mainly shade -enduring tree species such as white fir and beech, whose shares are to be increased to the wood in Germany. The conversion of labile, so of off-site pine forests in natural hardwood mixed stands therefore requires rejuvenation measures before the final removal of the dominant tree layer. At times, especially due pioneer crops of birch to the subsequent cultivation of beech trees to be planted under which later young beech aged 2 to 4 years.