The observations on Myzus persicae and Macrosiphum euphorbiae development were carried out on boxthorn (Lycium halimifolium) growing in various places of the city ofWroclaw in 1999-2001. They concerned the following issues: aphid population dynamics and aphid age and morph diversity in population structure. Aphids infested only certain boxthorn bushes and other bushes were free of these insects. M. persicae infested more bushes than M. euphorbiae did. The first species appeared 7-10 days earlier on boxthorn than the second one. Time of the maximum population density of both aphid species was similar. Age structure of M. persicae and M. euphorbiae populations was similar. The youngest larvae (L,-L,) predominated and the least numerous were alatae females. Coccinellids were the most numerous aphid predators on boxthorn.

Observations on the incidence, harmfulness and some elements of Cameraria ohridella control on white horse chestnut (Aesculus hippocastanum L.) were carried out in Wrocław, Poland, in 2001–2003. Three generations of the pest developed on A. hippocastanum. The leaf infestation by pest’s larvae increased systematically throughout the spring-summer season. Cultural control by removing the fallen leaves was suggested. Using this procedure, the abundance of the pest was considerably reduced, therefore, the percentage of the leaf damage was lower and the trees lost these leaves later in the season.

In the climatic conditions of Lower Silesia, Poland the European corn borer lays eggs on sweet corn during 3-5 week period between the 3rd decade of June and the 2nd decade ofAugust. The eggs are laid on leaves L1 to LS ofmain and lateral stems of the plants. Caterpillars start to hatch at the beginning ofJuly, but in 1998-2000 a massive hatching was observed only in the 2nd and in the 3rd decade ofJuly, whereas in 2001 - in the 3rd decade of this month and in the l st decade of August. Larvae are capable of migrating between plant rows on the soil surface, which was observed in 1998-2000 from the end ofJuly till the end of October. Most caterpillars migrated in the 2nd and in the 3rd decade of August and in the first days of September. The cob damage by caterpillars ranged between 31 and 46%. Delayed harvest caused a substantial increase in damage.

The trials conducted with selected chemical and biological insecticides in 1998-2000 showed the highest effectiveness of Karate Zeon 100 CS (lambda-cyhalotrine) in European corn borer (ECB) larvae control in sweet corn. The efficacy of biological insecticides containing Bacillus thuringiensis ssp. kurstaki: Biobit 3.2 WP and Lepinox WDG was very variable between the years. Reasons for insufficient efficacy of these products are discussed. The most appropriate time for the application of a chemical insecticide against ECB larvae are plant developmental stages since the beginning of pollen shedding to full blooming (63–67 BBCH scale). The efficacy of treatment was the highest at that time.

Observations on the development of the horse chestnut leafminer on red horse chestnut (Aesculus x carnea H.) were carried out in Wrocław, Lower Silesia, Poland, in 2001–2003. Three generations of the pest were recorded to lay eggs on the red horse chestnut leaves. Although females of each generation deposited eggs abundantly, the hatching larvae died after a short period of feeding in the plant’s leaves and the species did not complete its development on this tree. Mostly L₁ and L₂ larvae were found inside the leaf mines. The observed leaf damage was, therefore, negligible.

The attractiveness of uncultivated (weedy) and cultivated strips (planted with a mixture of flowering plants) and the adjacent sugar beet crop to Carabidae was studied in 1999–2000 at the Experimental Research Station near Wrocław, Poland. Obtained results showed that greater plant abundance and their diversity on weedy strips had a positive effect on the number of carabid beetles. Also more carabid species were identified in uncultivated strips than in strips of mixture of Phacelia tanacetifolia, Coriandrum sativum and Sinapis alba. The lowest number of species was trapped in sugarbeet crop and bare soil. The most numerous species in all treatments were Pseudoophonus rufipes, Anchomenus dorsalis (Pont.), Poecilus cupres and the species of the Bembidion genera.

In this study the effect of different grassland managements (cattle grazing with different intensities and mowing) on soil mesofauna, i.e. mites (Acari) and springtails (Collembola), was studied. Mites and springtails are the most numerous representatives of soil mesofauna organisms living in the upper soil layers (up to 5 cm). Soil mesofauna groups or species are commonly used as bioindicators of soil health. The experiment was carried out from 2007 to 2009 in the West Sudety Mountains, Poland. Pastures and meadows were under organic farming management, without pesticides or synthetic fertilizers, and restricted livestock density. Soil samples were taken three times a year (in May−June, July and October) from pastures grazed at different frequencies: once, twice and four times a year, alternate management (grazed and mown pasture) and mown meadow. Mites were identified according to orders or suborders (Oribatida, Gamasida, Prostigmata, Astigmata), while springtails to the species level. The data were analysed using a general linear model (GLM). The mesofauna taxa in relation to the treatment and date were analysed with the canonical correspondence analysis (CCA). The data from three years showed that most soil mesofauna assemblages occurred in significantly higher numbers on the pasture grazed once or twice and on alternate managed pasture than in pasture grazed four times a year and mown meadow. The CCA analysis showed the preference of most springtail species to pasture grazed once a year, while mites preferred pasture grazed twice a year and alternate management. The number of species and the abundance of the most numerous species (Protaphorura pannonica, Desoria multisetis and Folsomides parvulus) did not differ significantly between treatments. To summarize, cattle grazing once or twice a season or alternate management (grazing and mowing once a season) have a positive impact on soil mesofauna.