THE USE OF NITROGEN LEVELS IN TREE LEAVES AS INDICATIVE OF ABILITY TO GROW IN COLLIERY SPOILS

Abstract

Colliery spoils are known for showing variability and for presenting difficulties to afforestation. The problem in colliery that limit tree growth include element deficiencies and toxicity. Extreme spoil reaction is also a problem. Foliar analysis throughout the season is used as a tool. Nitrogen showed a change of concentration with season. Nitrogen concentration with season in Betula pendula is little different from that of Alnus glutinosa The ability of Alnus glutinosa to maintain a relatively high nitrogen level indicates the suitability of the species for growth on relatively nitrogen deficient sites.