Pine (Pinus sylvestris L.) Health Condition in Kaunas City Forests

摘要

This article reviews the dynamics of Scots pine (Pinus sylvestris L.) health condition in different Kaunas city districtsin 1994-2003. Health condition of Scots pine trees was estimated according to morphological indicatorial parameters:tree crown defoliation, foliage discolouration, amount of dead branches, needle retention, fruiting, state of tops andvisual damages. It was found, that health condition of pine trees was worsening reliably in 1994-1998, except Kleboniskis-2 and Lampedziai sample plots, and in 2001-2003 -- except Raudondvaris-2 sample plot. The mean crown defoliation ofall sample stands in 1994 was 29.0 +- l.9 %, in 1995 - 28.8 +- 2.1 %, in 1996 - 30.4 +- 2.2 %, in 1997 - 32.1 +- 1.9 %, in1998 - 33.5 +- 2.0 %, in 2001 - 25.9 +- 3.6 %, in 2002 - 29.2 +- 3.2 %, in 2003 - 34.3 +- 2.5 %. According to tree crowndefoliation the best health condition of Scots pine forests was estimated in Botanikos sodas sample plot, small defoliationwas found in Kleboniskis-2 and Eiguliai sample plots. The worst state of Scots pine was defined in Raudondvaris-2 sample plot,also great defoliation was defined in Kleboniskis-1, Palemonas-1, Palemonas-2, Panemune-1, Petrasiunai-1, Petrasiunai-2 and Viciunaisample plots. The greatest Scots pine crown defoliation (34.3 +- 2.5 %) in Kaunas city districts during our research period (1994-2003)was found in 2003.