Evoluzione Della Cerchia Legnosa in Quercus Aegilops L. a Tricase

Abstract

The author has examined the cambial activity and the formation of the annual ring in Quercus aegilops from February 1954 to February 1955. Material was collected at Tricase (Lecce) the only Italian locality where this oriental species grows although it is doubtful whether it is spontaneous.

Cambial activity starts in the middle of April both in the main stem and in the branches following flowering and bud development. It goes on for about five months until the second half of August forming a complete growth ring. This annual ring shows the normal sequence of early wood with wide vessels formed during the second half of April and the whole of May, intermediate wood with medium and small size vessels, parenchima, and fibres formed in June-July, and late wood with few small size vessels, parenchima, and fibres formed from the end of July to middle August.

There is no reawakening of cambial activity in autumn even if the climatic conditions are favourable. Tylosis are very easily formed in the wood vessels and by this process the plant can withstand the drought of the Apulian summer.