Ioan Taut

ASPECTS CONCERNING TO CHEMOTHERAPY OF FIGHTING AGAINST MEALY ATTACK FROM DURMAST NATURAL REGENERATION

Among the biotical natural causes which conduce on the amplify of the durmast drying phenomenon is considered first the durmast mealy attack with a large spreading produced by the pathogen Microsphaera abbreviata. The fungus, attack first leaves of saplings, or sprouts and continuous to the leaves and stems of mature trees. The most harmful attack effect are recorded in degraded rammels, in culture, nurseries and especially in young natural regenerations which are presented like foliage mass on large surfaces. Considering the importance of this to formation in new rammels where placed experiments in Sylvicultural Departments ray of: Dej, Gherla and Cluj, where was remark the effect of some fungicide (Systhane, Karathane, Trifmine and Alert) compared with the Bumper 250 EC standard produce. The results where synthesize in table 1. Table 1 The efficiency of SYSTHANE preventing the attack of Microsphaera abbreviata (f.c.Oidium alphitoides) Cvercinee regeneration Nr Infested leaves crt Product Sylvicultural department Conc. (%) Applied dose F(%) I GA Z E(%) Cluj 0,04 0,400 10,0 1,4 0,14 4,4 95,6 Turda 0,04 0,400 8,8 2,7 0,24 6,3 93,7 1 SYSTHANE Gherla 0,04 0,400 9,3 1,9 0,18 4,7 95,3 Cluj 0,03 0,300 11,6 1,9 0,22 6,9 53,1 Turda 0,03 0,300 11,2 2,1 0,24 5,9 94,1 2 BUMPER 250EC Gherla 0,03 0,300 11,0 2,0 0,22 5,5 94,5 Cluj - - 71,4 4,5 3,21 - - Turda - - 76,9 5,0 3,84 - - 3 Martor Gherla - - 80,5 5,0 4,03 - - According to obtained results and of ascertains we may conclude: - the chemotherapy represent an efficient solution fighting against the mealy attack; - to chose the right combination of substances must to be made according to their efficiency, value and the provision possibilities.

FOREST HEALTH STATUS IN CLUJ, ALBA AND MUREŞ FORESTRY DISTRICTS DURING THE 2000-2005 PERIOD ASSESSED ON THE EUROPEAN FOREST MONITORING NETWORK (16x16 km)

Multi-annual results concerning the forest health status in Cluj, Alba and Mures forestry districts, during the period 1990-2005, assessed in the forest monitoring system are different for every year, both for all species and for species groups and main species, individually. This variation of the damaged trees percentage (defoliation class 2-4) is due mainly to climatic condition, which in the last 20-25 years displays substantial fluctuations, especially concerning rainfall regime, soil water reserve and the thermal balance. Climatic changes determined this fluctuation, which is more and more intense, both at regional and global scale (Badea.O., 2005). In this context, for all species, in the survey period the damage trees percentage (defoliation class 2-4) registered highest values during the years 2001 and 2002 (57.3%, 56.9% respectively) and the lowest values during the years 2004 and 2005 (43.3%, 46% respectively). The resinous species proved to be healthier, with values of the damaged trees percentage between 29.4% and 43.1%, compared to the deciduous species with values between 47.3% and 65.8%. Individually, the Norway spruce and the beech were the least affected species, the values of the damaged trees percentage varying between 29.3% (in 2000) and 42.4% (in 2005) for Norway spruce, and between 63.4% (in 2002) and 40.5% (in 2005) for beech. The most affected species was the sessile oak with values of the damaged trees percentage up to 88.0% (in 2005). The significant forest health status improvement may be justified as a result of the occurrence of better and better climate conditions than in previous years (2000-2003), especially related to rainfalls with amounts higher in 2004-2005, when the water need was assured by the water stock of the autumn of 2003, and for the years 2004 and 2005, too.