REGENERATION OF WOODY SPECIES FOLLOWING BURNING AND GRAZING IN ASPEN PARKLAND

The effect of short duration, heavy grazing by cattle was evaluated 3 and 6 yr after burning and seeding of an aspen Populus tremuloides grove. Regardless of treatment, density of all woody species was lower 6 yr after burning than after 3 yr. Early or late season grazing reduced density of aspen and wild raspberry Rubus strigosus. Late season grazing promoted a greater density of unpalatable western snowberry Symphoricarpos occidentalis. Grazing reduced the height of aspen, preventing development of a forest canopy. Herbage production averaged 1700 kg ha-1, not differing between years 3 and 6: but the proportion of smooth brome Bromus inermis increased while orchard grass Dactylis glomerata declined. Burning of aspen forest in C Alberta followed by forage seeding and short duration, heavy grazing is an effective, economical range improvement tool. -from Authors