The article presents the results of the introduction of the North American flora woody species of the pine family (Pinaceae Lindl.) to the European North of Russia. The research purpose is to select the most valuable specimens for introduction into northern conditions from the tree species collection. The research has involved experimental, calculation, analytical, and comparative methods. The conclusion on the result of the introduction of a particular plant was based on the materials of long-term phenological observations, which were carried out according to the method of botanical gardens improved for the conditions of the European North of Russia. As a result of the introduction of North American species of the Pinaceae Lindl. family to the region, a large-scale test of foreign conifers was carried out for the first time; a collection of 2 species of fir, 4 species and 3 forms of spruce, 2 species of pine, and 1 species of Douglas fir was created. Most attention was paid to the introduction of species of the genus Pinus. Positive results of cultivation of Pinus contorta Loud. var. latifolia S. Wats. in the Dendrological garden allowed us to select it for further introduction testing in experimental plantations of the region. On plantations located in the Arkhangelsk and Vologda regions and the Komi Republic, 104.2 ths seedlings were grown from the seed samples, mostly from the northern natural range of this pine. Unfortunately, not all of the breeding material for the North American pine species tested was derived from natural growth sites, which puts into question some of the unsatisfactory results. Therefore, for Jack pine and Weymouth pine, it is advisable to use in testing additional samples from the most northern regions of their natural ranges in Canada. Many of these species are of both scientific and practical interest for forestry. To assess the economic value of those introduced species, adaptive capabilities of which in the conditions of the European North according to the results of studies are not in doubt, it is advisable to lay out pilot plantations in the region, similar to the already created plantings of North American lodgepole pine (Pinus contorta Loud. var. latifolia S. Wats.). The concentration of different species like balsam fir (Abies balsamea Mill.), Fraser fir (Abies fraseri (Pursch.) Poir.), American larch (Larix laricina (Du Roi) K.Koch.), Canadian spruce (Picea glauca Voss.), Engelmann’s spruce (Picea engelmannii Engelm.), black spruce (Picea mariana Britt.), Jack pine (Pinus banksiana Lamb.), lodgepole pine (Pinus contorta Loud. var. latifolia S. Wats.), and Douglas fir (Pseudotsuga menziesii Mirb.), involving several seed origins from the most northern regions of its natural range for each, in 2-3 forest areas will allow creating a valuable introduction object; scientific and practical importance of those mentioned cannot be overestimated.
Seed Stratification of Engelmann Spruce and Lodgepole Pine: The Effect of Stratification Duration and Timing of Surface-drying