The Effect of Soil Properties on Weed Distribution in Turkish Apple Orchards

Abstract

Soil properties affect weed composition and weed density in orchards. Understanding the relationship between soil properties and weed distribution would allow selection of the best weed control strategies. The current study aimed to examine the correlation between weed density and soil physicochemical characteristics in apple orchards. Survey studies were performed in 143 apple orchards for the purpose. Weeds were counted and soil samples were taken at the intersection points for their physicochemical analysis. Canonical correspondence analysis (CCA) was used to assess the effects of different soil factors and altitude on grassland species and weed distribution. Of the identified weed species, 129 belonged to 33 families, two of which were monocotyledonous and 31 were dicotyledonous. The species mostly identified in apple orchards belonged to the Asteraceae (21 species), Poaceae (15 species) and Brassicaceae (13 species) families. The aggregate stability, Ca, P₂O₅ and CaCO₃ contents of the soils were significantly different between the apple orchards. The weed species Echinochloa crus-galli (L.) P. Beauv., Cuscuta polygonorum L. and Acroptilon repens (L.) D.C. were identified as indicators of clay soils and the species Poa trivialis L., Medicago sativa L. and Plantago lanceolata L. were identified as indicators of sandy soils. The species Avena fatua L., Bifora radians Bieb. and Cuscuta polygonorum L. were identified as indicator plants and the species Bromus tectorum L. Agropyron repens (L.) Beauv. and Tragopogon latifolius Boiss. were identified as cosmopolite species which are able to adapt to any kind of soil.