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Báo cáo khoa học: "An artificial regeneration system for establishing northern red oak on dry-mesic sites in the Lake States, USA"

Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp quốc tế đề tài: "An artificial regeneration system for establishing northern red oak on dry-mesic sites in the Lake States, USA. | 543 Ann Sci For 1993 50 543-552 Elsevier INRA Original article An artificial regeneration system for establishing northern red oak on dry-mesic sites in the Lake States USA RM Teclaw JG Isebrands USDA Forest Service North Central Forest Experiment station Forestry Sciences Laboratory PO Box 898 Rhinelander Wl 54501 USA Received 6 January 1993 accepted 2 June 1993 Summary Artificial regeneration of northern red oak is difficult to achieve in the Lake States USA. A replicated study was established in northern Wisconsin in 1990 to determine the effect of overstory density and understory competition on the performance of bareroot and containerized northern red oak seedlings on dry-mesic sites. The relationship between seedling performance and the number of first-order lateral roots on the seedlings was also tested. Seedling performance was evaluated under 3 overstory densities each 0.3 ha a clearcut 25 and 50 crown covers in combination with and without understory vegetation control with herbicide. Height growth was greater for containerized seedlings than bareroot stock after 2 and 3 growing seasons. After 2 yr seedling growth was greatest in the sprayed clearcut plots but was only slightly greater than the unsprayed plots under the 25 crown cover bareroot 25.5 vs 23.8 cm and containerized 33.0 vs 31.2 cm respectively . After 3 yr seedling height growth was significantly greater in the unsprayed plots under the 25 crown cover for both the bareroot and containerized seedlings when compared to all other overstory understory treatment combinations examined in the study. Early performance results suggest that the light shelterwood silvicultural method e 25 crown cover without chemical control of vegetation is preferred for establishing northern red oak on dry-mesic sites when compared to the more traditional management schemes. Quercus rubra I clearcut herbicide shelterwood bareroot stock containerized stock silviculture Resume Une technique de regeneration artificielle .