Abstract MEISL, T., DUBSKÝ, M., ŠRÁMEK, F., NEČAS, T.: The eff ect of clay amendment on substrate properties and growth of woody plants. Acta univ. agric. et silvic. Mendel. Brun., 2012, LX, No. 8, pp. 163-170 This work deals with the eff ect of two clay products diff ering in particle size distribution on properties of growing substrate and on growth of containerized woody plants in substrates amended with these clay products. Fine and coarse clay were added to a peat substrate, each at two rates. The peat substrate without clay was used as a control. The substrates were tested in experiments with two woody ornamentals (Thuja occidentalis 'Smaragd' and Prunus cistena). Chemical and physical properties of the substrates were measured according to European Standards before planting. Proportion of water categories diff ering in availability to the plants were calculated from retention curves measured on the sand box. Properties of substrates in containers with and without plants were evaluated in the same way at the end of the culture. Clay addition changed chemical and physical properties of the tested substrates in terms: available nutrients content, particle density, bulk density, total pore volume, easy available water, water buff ering capacity, air capacity, and shrinkage. The eff ect of fi ne clay was much stronger. In comparison with the clear eff ect of clay addition on the substrate chemical and physical properties, the eff ect on the growth and quality of model woody plants was not so explicit
