The role of near-surface lateral roots in the life cycle of aspen in the central Rocky Mountains

• Published in: Forest ecology and management 1993, Vol.61 (1), p.157-170
• Main Authors: Shepperd, W.D., Smith, F.W.
• Format: Article
• Language: English
• Subjects: Agronomy. Soil science and plant productions; Biological and medical sciences; Forest management. Stand types and stand dynamics. Silvicultural treatments. Tending of stands. Natural regeneration; Forestry; Fundamental and applied biological sciences. Psychology; Populus tremuloides; Stand types and stand dynamics. Silvicultural treatments. Tending of stands. Natural regeneration
• ISSN: 0378-1127; 1872-7042
• DOI: 10.1016/0378-1127(93)90196-T

Above- and below-ground development was studied in 47 aspen ( Populus tremuloides Michx.) clones in the central Rocky Mountains of Colorado. Our objective was to determine if characteristics of roots larger than 4 mm and within 0.2 m of the surface could be related to the life cycle of vegetatively regenerating aspen. We found that root diameter increased and end-of-season nonstructural carbohydrate content decreased with average stem diameter. Root volumes were lowest and nonstructural carbohydrate contents highest in clones between 20 and 80 years of age. However, root volumes did not change for several years after vegetative coppice regeneration of clones. Initial root/shoot ratios declined rapidly as young suckers grew, but slowed abruptly 10–25 years after regeneration. Aspen lateral root systems appear to adjust to above-ground conditions in three phases over the life cycle of a clone: (1) establishment of new suckers; (2) efficient growth from youth to mid-age; (3) maintenance at older ages.