This manuscript contains information on the species composition of weed communities in orchards in Poland and other countries of the temperate climate zone. The manuscript deals with the influence of weeds on crops and the interaction between the weeds and other living organisms. The main methods of weed regulation are described. Characteristics of the particular crops – fruit trees and small fruits – and solutions that are either objects of study or have already been introduced into practice, are presented. Advantages and disadvantages of different methods of weed control are discussed, such as soil cultivation and tillage, cover crops, mulches, herbicide use, and flame burning.

Research on synanthropic flora was conducted in the orchards of central Poland (near Skierniewice, Łowicz and Grójec). In the 2007-2010 time period, 390 phytosociological releves were taken, which included herbicide fallow under trees, swarm of inter-rows, tillage places, trodden and rutty places, roadsides, boundary stripes and drainage ditches. In the examined orchards the occurrence of 186 species belonging to 39 botanical families was noted. The most numerously represented were: Asteraceae (21%), Poaceae (15%), Brassicacea (8%) and Fabaceae (7%). In the examined orchards, 60% of the found species occurred occasionally or rarely. Those species which were found at the 15% level were: Equisetum arvense, Polygonum aviculare, Chenopodium album, Amaranthus retroflexus, Stellaria media, Capsella bursa-pastoris, Convolvulus arvensis, Viola arvensis, Epilobium adenocaulon, Conyza canadensis, Taraxacum officinale, Poa annua, and Echinochloa crus-galli. All of these species which occurred at the 15% level were most frequently noted in the herbicide fallow and were recognised as the most significant orchard weeds. The most numerous group in the examined orchards was made up of the therophytes (50%), which predominated over hemicryptophytes (31%) and geophytes (10%). Apophytes - native species (59%) predominated over archeophytes (33%) and kenophytes (8%). Within the vascular flora of the examined orchards, those which were predominant were the segetal species (26%), ruderal species (21%) and meadow species (19%).

Following the winter of 2009/2010, an assessment of frost damage was carried out on the vines of 40 wine cultivars and 32 table grape cultivars grown in central Poland (Skierniewice, latitude 51° 57' N, longitude 20° 08' E). The minimum winter temperature of -28.1°C was recorded on 26 January 2010. Cultivars were assigned to five classes of different frost tolerance, according to information on the percentage of frozen buds: very resistant (below 1.9%), resistant (2 - 24.9%), medium susceptible (25 - 74.9%), susceptible (75 - 95.9%) and very susceptible (above 96%). The numbers of wine and table cultivars in each class were as follows: very resistant - 5 (wine) and 3 (table), resistant - 2 and 5, medium susceptible - 15 and 10, susceptible - 13 and 9 and very susceptible - 5 and 5. The most tolerant were the ‘Alwood’, ‘Delaware’, ‘Fredonia’ and ‘Zilga’ interspecific hybrids of the Vitis labruscana group; the ‘Aurore’, ‘Marechal Foch’ and ‘Leon Millot’ hybrids originating from V. vinifera, V. rupestris, V. riparia and V. lincecumii and ‘Sibera’ originating from V. vinifera and V. amurensis. More than 96% of buds froze on the vines of some interspecific hybrids (‘Arkadia’, ‘Fanny’, ‘Kodrianka’ and ‘Lilla’). ‘Ortega’, ‘Nektar’, ‘Cserszegi Fueszeres’, ‘Riesling’ and ‘Chasselas Dore’ from the V. vinifera cultivars showed the best tolerance to frost damage (42.5-62% of frozen buds). The buds of the V. vinifera cultivars ‘Acolon’, ‘Dakapo’ and ‘Favorit’ all froze. Plant parts covered with soil and snow were not exposed to significant damage, even in the case of susceptible cultivars.

The aim of the study was to analyze the occurrence of segetal and ruderal weeds in young apple and cherry organic orchards, where weeds under tree canopies were controlled mechanically with a rototiller, and in conventional orchards, where post-emergence herbicides were used. The research material consisted of phytosociological relevés recorded according to the Braun-Blanquet method, in three organic and three conventional orchards, situated near Skierniewice (central Poland), in 2010-2013. On the basis of the collected source material, species composition for the synanthropic flora, as well as phytosociological stability, the cover factor, and weed infestation rate for the analysed species were determined. The total number of the recorded weeds and the average number of weed species in a single relevé were for each of the three organic orchards greater than for the conventional orchards. The organic orchard situated in the same location as the conventional orchard was characterized by a greater biodiversity of flora. Systematic shallow cultivation of the soil, without herbicide treatments, resulted in the proliferation of perennial weeds.