Weed control measures in Christmas tree plantations of Abies nordmanniana and Abies lasiocarpa on agricultural land

• Published in: New forests 2009-09, Vol.38 (2), p.143-156
• Main Authors: Sæbø, Arne, Fløistad, Inger Sundheim, Netland, Jan, Skúlason, Brynjar, Edvardsen, Øyvind Meland
• Format: Article
• Language: English
• Subjects: Agricultural land; Biomedical and Life Sciences; Forestry; Grasses; Ground cover; Life Sciences; Seedlings; Trees; Vegetation; Weed control; Weeds
• ISSN: 0169-4286; 1573-5095
• DOI: 10.1007/s11056-009-9136-9

Abies nordmanniana and Abies lasiocarpa, established for Christmas tree production in southwestern Norway (58°44'N, 5°38'E), were treated with different weed control methods, including chemicals, use of black plastic mulch, grass or clover as ground cover, living mulch and mechanical hoeing. Ground cover with black plastic mulching resulted in the best growth and quality in A. lasiocarpa; the least favourable treatment was when grasses were allowed to grow close to the trees. Unless measures were taken to remove this competing vegetation, the ground cover grew over the trees, smothering 94% of them. A. nordmanniana plants grew to the same height on plots with no weed control as on plots with thorough weed eradication. Stem diameter decreased on plots with ground vegetation compared to seedlings grown in the weed-free environment. The use of Trifolium repens as ground cover decreased height growth by 30% compared to thorough weed control. Both grasses and clover sown as living mulch, damaged the trees more than did natural weed vegetation.