The Sprouting Capacity of 8–21-Year-Old Poplars and Some Practical Implications

We investigated the sprouting capacity of poplar stumps in ten 8–21-year old stands growing on former farmland in Sweden situated between 55°N and 60°N. Seven of the stands were planted with the clone OP-42 (Populus maximowiczii Henry × Populus trichocarpa Torr. and Gray), one with black cottonwood (Populus trichocarpa Torr. and Gray) and two with unidentified clones. The poplars’ mean age was 17 years (range 8–21); six of the stands were growing on clay soils, two on tills and two on loam. The studied sprouts were 1–7 years old. Stump sprouting was observed in all studied stands. The number of sprouts per living stump decreased as sprout age increased. The mean dry mass of all sprouts stump was 16.1 ± 14.0 (range 3.3–37.2) kg. A biomass equation was constructed for estimating sprout biomass from the sprouts’ diameter at 10 cm above the ground (D10). The mean total sprout weight per hectare for sprouts amounted to 16.9 ± 14.6 (range 1.2–41.3) tons ha when calculated for the actual living stumps in the studied areas.