Root density, root length, root biomass and rooting pattern were surveyed in pure and mixed forest stands of Douglas fir and beech. Root length was largest in a 64-year-old pure beech stand (184 000 km/ha) and smallest in a 60-year-old pure Douglas fir stand (67 000 km/ha). In the mixed stands the soil layers at 0.15-0.30 m and 0.30-0.45 m depth were rooted more intensively than those in the pure stands. Moreover, specific root lengths of Douglas fir and beech were larger in the mixed stands, which may indicate underground competition. This has led to different use of the soil resources.
- plant development