Ideal field shelterbelts for the prairies would consist of tall, long-lived trees which are not competitive with nearby crops and do not occupy too much land. The PFRA Shelterbelt Centre at Indian Head presently recommends mainly green ash and caragana for field shelterbelt use. These species have many desired characteristics. Caragana is very long lived and non-competitive. Land occupation is normally less than 15 feet.
Green ash is tall, long lived and hardy.
It is also relatively non-competitive and compact in form. The only drawback to this species is that it leafs out late in the spring, usually after the period when the most severe wind erosion occurs. Although a spacing of two metres between trees is presently recommended by the Shelterbelt Centre, this represents a compromise since more desirable snowdrift patterns are achieved while some effectiveness against wind erosion is sacrificed. For these reasons, mixed plantings of green ash and caragana may be the most effective in reducing wind erosion. Alternative trees being evaluated by Shelterbelt Centre staff include Siberian larch, Scots pine, Ussurian pear and Bur oak.