Appraisal of small-leaf linden (Tilia cordata Mill.) growth conditions near the major arterial streets in Alytus city

Abstract

The predominant variety among the town greenery he research (2009–2012) was done in Alytus city as a part of activities designed to preserve as well as to plant new trees as an aesthetic, ecological, historically and culturally significant element of the local landscape. Soil samples were taken from the topsoil (0-20 cm) and the chemical analyses were carried out by the appropriate conventional methods at the Agrochemical Research Laboratory of the Lithuanian Research Centre for Agriculture and Forestry. The 5 grade scale in relation to signs of damage has been applied for tree condition assessment. The investigations revealed not so favourable soil conditions for the small-leaf linden trees near the major arterial streets in Alytus city. Although no risk of soil chemical pollution with Cl and Na was determined, the soil was found to contain too small quantities of such important nutrients as K and P. Besides, pH here is above 7, and this alkaline environment might complicate the uptake of these essential macronutrients by the plants. It was found that the greatest negative impact on the state of small leaf linden was due to physiological damages (defoliation, dischloration, leaf necrosis, dry branches) and biotic factors: fungal diseases (sooty mould fungi Cladosporium herbarum, Leptoxyphium fumago; leaf spots agents Apiognomonia errabunda, Mycosphaerella millegrana and pests (Caliroa annulipes, Eryophyes tilia-nervalis, Eucalipterus tiliae, Schizotetranychus tiliarum).