The influence of soil preparation on the development of ground vegetation in forest plantations on arable farmland and forest clear-cut areas

The influence of soil preparation on the development of ground vegetation during the establishment of forest plantations was studied. It was found that in the first-year plantations on former farmland the least biomass of ground vegetation develops on furrows. Complete soil tillage to the depth of 22-27 cm, ploughed in berms or elimination of weeds with Roundup Bio may reduce the biomass of ground vegetation by up to two times. Soil ploughing in berms or piles always reduced the mass of weeds. In the second year of plantations' growth, differences in the biomass of weeds among different soil preparation treatments decreased. On fresh clear-cut areas of fertile mineral soils any mechanical method of soil preparation reduced the biomass of ground vegetation. With increasing soil preparation depth (down to 40 cm) and the width of the strip (up to 100 cm), the biomass of ground vegetation decreased. The least (4-9 times less compared with unprepared soil) ground vegetation biomass was observed when the soil had been prepared in furrows, berms or piles. Soil preparation method affected also the height of ground vegetation. It depended on soil fertility and moisture content, weed species, spring and summer weather conditions. The shading class of seedlings and the volume of plantation tending depended on soil preparation method too. Seedlings planted on wide (100 cm) furrows and on 30 cm high piles were the least shaded, while those growing on unprepared, completely ploughed soil or on inverted humus mounds experienced the greatest suppression.