Effects of bottom cutting on poplar seedlings growth and uniformity at different ages and clones

The purpose of this study was to investigate the effects of bottom cutting on seedlings growth and to measure seedlings growth at different ages (1/1, 1/2 and 2/3 years) and their growth uniformity. For this reason 52 clones of native and axotic Populus species were planted in an experimental nursery. The seedlings were propagated by cutting method and planted at 120 × 30 cm space. The seedlings were cut at the second year of nursery plantation and their growth parameterrs were measurrd at end of the second and the third years growth period. The species were P. nigra, P. alba, P. euramericana and P. deltoides and their clones number were 27, 14, 7 and 4, respectively. The SPSS computer program and the T-Test method (Duncans Multiple Range Test) were applied for data statistical analysis. The effects of bottom cutting on seedlings growth increment and uniformity were significant. there was significant different between the seedlings growth in different clones