The systemic insecticide dimethoate (0.20 g active ingredient and 0.30 g active ingredient per cm dbh, in 1990 and 1991 respectively) was injected into European larch trees to determine its effectiveness in controlling cone and seed insects. Percentages of cones and seeds damaged by insects and germination of seeds were assessed. The treatments were more effective against the larvae of Strobilomyia spp. and Retinia perangustana, and less effective against those of Resseliella skuhravyorum. The percentages of seeds damaged by the above mentioned pests were diminished by 47-94 %, 37-83 % and 30-39 % respectively. In addition, the treatments increased the percentage of filled seeds, and consequently the overall effectiveness was of 55.2 % in 1990, and 86.6 % in 1991. They did not reduce the percentage of germinated seeds. The best results have been obtained when the treatment was conducted earlier, that means at the beginning of R. skuhravyorum eggs hatching. Therefore, we reccomend the treatment to be done just prior to female bud flush.

The paper presents some aspects concerning the use of different species in ecosystem monitoring. The introduction of bioindicator species for the ecological control (and future protection) of ecosystems dates from about thirty years but in the recent period more and more species are identified and used for this purpose. If at the begining the accent was posed on vegetal species as indicator of environmental contaminants, in our days animal species are used as indicators of all kinds of perturbations and stresses of ecosystems, not only damages caused by pollution. The biomonitoring presents an special interest for developing countries, like ours.

Norway spruce (Picea abies (L.) Karst) - one of the most important forest species in both Europe (about 34 million ha) and Romania (about 1.4 million ha) - has been highly expanded in monocultures outside of its natural range since mid- 19th century. Unfortunately, despite their many advantages (easy establishment, quick growth, high production, multiple uses of timber etc.), Norway spruce pure stands are facing many problems being especially subjected to wind and snow damages. Taking into account these facts, the article outlines the most important factors influencing Norway spruce stand stability such as initial spacing (stocking) and early silvicultural interventions. It seems obvious that two solutions for a better stability to snow damages at early ages exists: low stocking (wide spacing) at planting (maximum 2,000-2,500 plants per ha) and high stocking (narrow spacing) at planting (4,000-5,000 plants per ha) but followed by high intensity cleaningrespacing started no later than end of saplingbeginning of thicket stage. Under present Romanian conditions, facing many economic constraints (e.g., high cost of planting and tending; lack of labour force), the solution of low stocking (wide spacing) at planting as already stated at the beginning of 1980’s but never applied on a large scale seems more feasible and realistic

Bulk precipitation were collected in 6 stations located în forest ecosystems from north and south Romania, during 1998-2002. Samples were analysed in the laboratory for pH and the major anions and cations. For the 3 stations in the north only data from 1998 to 2001 were completed. The fluxes of mineral ions in bulk deposition measured in 2002 for the 3 stations located in south Romania were compared to the means determined in 1998-2001. The inputs decreased for S-SO4 2- ( 19-25 %), N-NO3 - ( 29-73%) and Cl- (cu 9-10%). For H+ , N-NH4 + , Na and K+ no trends were clearly observed. Ca2+ and Mg2+ fluxes in bulk deposition decresed in 2002 with 39-66% and respectivly 31- 78% related to 1998-2001. Comparison of the mean ions fluxes registred in the north and south Romania during 1998-2001 revealed that excepting for H+ and Cl- , which were higher in north than in south, for all the other ions the values determined in north were equal (N-NO3 - ) or lower (S-SO4 2-, N-NH4 + , K+ , Mg2+, Ca2+) than those measured in the south part of Romania. Values of mineral ions inputs registred in Romania from 1998 to 2002 were compared to those calculated in some zones of Europe from 1993 to 1998. Fluxes of H+ , Cland Na+ were relatevly low compared to those form Europe. The SSO4 2- fluxes were moderate and high and the NNH4 + , K+ , Mg2+, Ca2+ were high în Romania related to those determined in Europe.