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The species Nezara viridula (L.) or green stink bug is one of the most recent nonautochthonous species that invaded agroecosystems in our country. The lack of natural enemies makes this insect rapidly spreading from the locality to the locality and from the geographic area to the other. It is not known exactly what causes enlargement to geographically or ecologically different areas. Globally, the insect is present both in warm and temperate areas. At Europe level it is found in almost all geographic points except the northern point. The observations of this scientific paper have been made in the southwest of Romania, more precisely at the level of the Caras-Severin County, which has a great variety of relief forms, from the plain to the mountains (from 168 m to 1000 m). The effective or size of the insect population at a given time, such as spatial distribution, has been the main parameters analyzed in terms of temperature and humidity but also geographical altitude. The observation period was in June-October of 2016 and 2017. Because they are large insects, trapping them with pheromone or colored traps is not conclusive and rather quantification by direct observations on the preferred plants (tomatoes, cucumbers, beans). To analyze population size and distribution in 8 different areas, 10 samples (two monthly sample/area) were processed. Correlations between environmental factors (temperature, humidity) have shown that high temperatures and low humidity favor activity and insect movement. The great presence of the species was mainly observed in areas with lower altitude of the county and less or no in high altitude areas, respectively at values ranging from 168 to 300 m. [ABSTRACT FROM AUTHOR]

Nezara viridula, popularly known as the green stink bug, is a pentatomide species considered to be invasive for our country. Its place of origin is a tropical area in Africa. Continuous adaptation to other temperate, cooler areas is a feature of adaptability and serious consideration. Evolution of the species at European level highlights its presence in 25 countries. Being a species recently introduced in Romania (2010), monitoring activities are encouraged. Previous studies have highlighted the presence of the species in the western part of the country, more precisely in Timis County. Partial references of its presence in the southwest of the country have convinced us that through this paper we will focus on monitoring activities. The main purpose is to identify new places where the pest is present and, of course, to identify new host plants. The damage to crops and repercussions on the productions were detected. The observations were carried out between June and October 2017. The target area was Caras Severin County. There were 5 observation points (OP) for 8 localities or observation zones (OZ), so that the 40 OP cover the entire county. The research methodology is an adapted one, currently there are no monitoring methods and population evaluation with the specificity of the Nezara. For this purpose, field movements were conducted, where direct readings were made on the plants and also samples of attacked plants were taken. Field activity was mixed with laboratory activity to identify the stage of development and the host plant. The obtained results showed that most exemplars were found in BSZO3PO4 in the Bocsa area, August (with an average of 87.6 individuals/5 readings). Insects have also been observed in Oravita and Moldova Noua, Caransebes and Baile Herculane, respectively in the ORZO4PO2, MNZO5PO3, CSZO2PO2 and BHZO8PO3 (4) points. The host plants identified in 2017 were beans, tomatoes, cucumbers and raspberries. In the observation areas of Anina, Resita and Otelu Rosu, no individuals or plants with characteristic symptoms were found. In comparison to the previous years, the species has modified its habitats and also the population level. [ABSTRACT FROM AUTHOR]

Green bug (Nezara viridula) is a pest recently reported in our country (respectively in 2010, Timisoara). It is known to be present in different areas and different plants. It has a different food regime from one area to another. Therefore, in this paper we proposed an approach to knowledge the population size in Caras Severin County, from the South-West of Romania. The research covered all areas of the county and were carried out during the years 2015-2016. Observations were conducted in eight cities (Resita, Caransebes, Oravita, Anina, Bocsa, Moldova Noua, Herculane and Otelu Rosu). In each locality was determined several areas and observation points (ZO-5/OP-5) representing the previously established crops. Readings were performed monthly beginning in June and ending with October. The plants under the macroscopic observations were part of both agricultural area and the horticultural. The results of the monitoring and measurement of specimens found have shown an abundance of species in areas Bocsa, Oravita and Herculane. Maximum values recorded in observation points reached 80-100 individuals. Few individuals were made in Resita and Caransebes (8-12 individuals). Most specimens were observed during August-September. In all areas monitored prevailed larvae and nymphs. As regards the type of crop/plant, it can be noted that the higher presence was indicated on corn, beans, tomatoes, and berries. Bug has not been reported in towns: Anina, Moldova Noua and Otelu Rosu. The presence of the species was noted especially in the lowlands of the county and less or no in higher areas. Bug current state in the Caras-Severin County are of installation and ongoing monitoring. [ABSTRACT FROM AUTHOR]

Since the 1950s, wind has represented one of the main disturbances to forest ecosystems in Europe, causing an increase in the frequency and amount of trees uprooted or broken by wind. Such phenomenon has also increased the incidence of compression wood in the xylem of remnant trees, thus leading to a general decrease in timber quality. In this study, we aimed to determine how wind regime affects the incidence of compression wood by reconstructing its chronology at both inter- and intra-annual scale using dendroclimatic methods. Six silver fir stands at different elevations were selected in central Romania, and compression wood time series were obtained from both increment cores from standing trees and radial discs from felled trees. Wood-structure variables were statistically analyzed as time series, while fluctuations of wind frequency and speed over the period 1921-present were reconstructed based on meteorological data. The structural response of sampled trees to wind was assessed based on the annual fluctuation in the frequency and intensity of compression wood. Results showed that the incidence of compression wood in the time series was synchronized with the intensity of the wind, rather than its duration. Wind regime in December of the preceding calendar year was significantly correlated with the frequency of compression wood, whereas its intensity was significantly correlated with wind load of previous September. The response of cambium to the wind stimulus increased with distance from the tree collar, peaking in the section at the base of the crown. At a decennial scale, only high-intensity wind stress triggered structural responses in the studied trees. Wind effects on xylogenesis in the analyzed stands increased over the last decades as a consequence of the local forest management. A bet - ter understanding of the structural response of forest trees to wind regime may explain how individual and groups of trees compete for stability and can help to improve forest management strategies in windy regions. [ABSTRACT FROM AUTHOR]