Current issue: 54(5)
Under compilation: 55(1)
Shrinking of timber when drying is a phenomenon that causes variation in measuring of timber in timber trade and on using the timber for construction or other purposes.
The data for the article consists of 332 increment core samples from pine trees different ages, sizes and growth rate. There were collected in years 1910-1912 in Finnish Lapland, regions Utsjoki and Inari. The increment cores were collected on the height of 1.3 meters in south-north direction straight crosswise through the whole tree. The samples are 6mm thick. The diameter of the samples was measured immediately after making the sample and after several years’ storage in room temperatures. Also the age of the trees was determined.
The results are presented in tables. The degree of shrinkage varies heavily between the samples but stays anyhow between 1.5 and 3.9%. The mean degree of shrinkage for 314 samples was 2.9%. The results seem to indicate that the bigger the shrinkage the denser the annual growth ring system of the tree, meaning the slower the growth has been. The older and of diameter bigger trees shrink less than younger and smaller trees.
The purpose of the study was to determine the effects of the origin of seeds and the location of cultivation of Scots pine (Pinus sylvestris L.) on certain properties particularly important to the pulp industry. The research material consisted of six parallel trials of the same 12 provenances. Increment cores were taken of a total of 1,267 sample trees, 19 years old. The location of the trial site generally affected the properties to a larger extent than the origin of the seed. The effect of the variation of wood density and fibre yield on the cultivation values of the provenances was only a few percentages on average, however, at most the effect was nearly 10%. Eastern Finnish provenances adapted well to western Finnish conditions.
The PDF includes an abstract in Finnish and French.