Effect of Betula pendula Admixture on Tree Growth and Branch Diameter in young Pinus sylvestris Stands in Southern Finland
2003
Valkonen, Sauli | Ruuska, Juha
The effects of a birch admixture on the height and diameter growth and maximum branch diameter in planted Scots pine stands was studied using models constructed with a data set from 13 stands of 9–16 yrs of age and 2–8 m dominant height on average sites on mineral soils in southern Finland. The density and height of the birch varied highly between and within stands. Simulated results indicated that the pines were capable of keeping up in height growth with birches that had originated from seed. Even a very high number of birches (10 000 stems ha−1) had virtually no effect on the height growth of the pines. The number of birches had a pronounced effect on the diameter growth and the maximum branch diameter in pine. Retention of a temporary birch component in young pine stands seems a feasible way of mitigating the adverse effects of low planting densities on the external quality of pine.
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