Current issue: 55(2)
The daily height growth rate of several larch species and progenies (Larix decidua, Larix sibirica, Larix laricina, Larix leptolepis) grown in a plastic greenhouse and in the open was measured. The growth pattern indoors was completely different compared with the normal outdoor growth pattern. The onset of growth took place in the greenhouse much earlier than outdoors and the phase of increasing growth was much shorter, as was expected. However, the phase of maximum growth was unexpectedly long. This fact suggests that there is great potential for using greenhouse cultivation to change the growth pattern of cultivated plants in order to obtain more complete utilization of the potential growing season.
The PDF includes a summary in Finnish.
Foreign tree species have been planted in Finland since 1900s, the most famous being Larix sibirica plantations in Raivola in Karelia, which now belongs to Soviet Union. One of the largest larch plantations of Finland today is situated in Tuomarniemi, in Central Finland. Ten larch stands were established in Tuomarniemi between 1912 and 1937 mainly by planting. The stand established in 1937 was sown. The trees represent five larch species: Larix sibirica Ledeb. (5 stands), Larix gmelinii var. kurilensis (2 stands, current name probably Larix gmelinii var. gmelinii), Larix americana Michx. (1 stand, now Larix laricina), Larix decidua Mill. (1 stand) and Larix occidentalis Nutt. (1 stand). The total area of the larch stands is 82.5 ha. This paper reports the studies made in the plantations in 1958.
In Tuomarniemi larch grows well in many types of soil from Vaccinium type sites to fresh mineral soil sites. The age of the stands varies from 19 to 48, height from 12 to 24 metres and annual growth from 5 to 12 m3/ha. Larix sibirca has the best stem form of the species, followed by L. gmelinii var. kuriliensis. Easiest to split is the straight-grained L. gmelinii var. kuriliensis. L. sibirica is almost as easy to process. The wood of L. decidua, on the other hand, is often spiral-grained and tough. The trees are seldom infected with decay fungi.
The PDF includes a summary in German.