The arboreal introducents of seed controlling experimental station in Pushkin town (St. Petersburg, Russia)

Arboretum at Puskin occupies an area 2,2 ha. It has been existing since 1926 with personal, participation of academician N. I. Vavilov. At present it is situated on the territory Seed Controlling Experimental Station (SCES) which is under St. Petersburg Administration. Arboretum has dendrocollection, including arboreal plants of 225 species and forms of 60 genera 30 families, 33 of them represent local dendroflora. Conifer introducents include 21 species and 14 cultivars, angiosperm number 146 species and 14 cultivar (trees, shrubs, semishrubs and lianas). 47 % of introducents represent different floristical regions of European and Asian parts of Russia, other species were introduced from floristical provinces of South and West Europe, the Mediterranean countries, Middle and East Asia, North America. About 90 % of species and cultivars-introducents and cultivars are winter-hardy, although frosts hear can exceed -40 0C. More then 100 species produce fruits and seeds of good quality which are used for growing their progeny. 20 species of introducents renew themselves that is to say naturalizate. Especially are interesting in arboretum introducents and cultivars, that aren't presented in other dendrocollections of St. Petersburg (Picea breweriana, Picea omorica cv. 'Nana', Pinus contorta var. murrayana, sambucus nigra L. 'Laciniata' ets.) and also plants of «Red Book of Russia» (Taxus baccata, T. cuspidata, Betula schmidtii, Partenocissus tricuspidata ets.). In this article there is full catalogue of arboreal introducents with a description about each taxa of floristical provinces of his natural areal, age, form, group of gross, winter-hardy and adaptation level. Fundamental directions of further development of denrocollection are determined. Bibliography - 21 names. St. Petersburg State Forest-Technical Academy, State Seed Controlling Experimental Station (Pushkin)