INFLUENCE OF DIFFERENT NURSERY CONTAINER MEDIA ON ROOTING OF SCOTS PINE AND SILVER BIRCH SEEDLING AFTER TRANSPLANTING

Scots pine (Pinus sylvestris L.) and silver birch (Betula pendula Roth .) seedlings were grown in containers filled with growth media based o n medium-textured sphagnum pear, coarse perlite and fine sand. The see dlings were then planted into fine and coarse sandy soils in 2.21 pots , which were subjected to two water-content treatments (only one for b irch). After the seedlings had grown five weeks in a greenhouse, rooti ng into the surrounding soil and shoot growth were measured. Addition of perlite and sand to peat medium slightly affected rooting; thus sug gesting minor effects on seedling establishment. However, nitrogen con centration of the seedlings varied between growth media and correlated positively with rooting into the soil. The particle size and water co ntent of the soil affected considerably rooting of the seedlings. Seed ling height at the time of planting did not affect rooting or shoot gr owth. The fact that the fewest out-grown roots occurred in the dry fin e sandy soil, suggests that dry soil together with high strength and r esistance to root penetration reduce rooting and water uptake by conta iner seedlings most and may thus cause water and nutrient stresses to seedlings after outplanting.