Effects of wind sway on stem form and crown development of Scots pine (Pinus sylvestris L.)

Summary The distribution of growth was examined in 45-year-old Scots pine (Pinus sylvestris L.) trees stayed with wires attached at 30% and at 30% and 60% of the tree height, and in trees with a metal sail attached in the top of the crown. The treatments commenced in 1983 and 16 trees per treatment, including the control, were sampled in 1988. Increments of stem diameter, height, and volume in treated and control trees were estimated from stem and branch mensuration. Staying the trees promoted radial growth by about 10% above the point of attachment. Increasing the wind sway with sails promoted radial growth below the crown. Changes in the distribution of growth within the crown were not as obvious as the changes along the stem below the crown.