White spruce artificial regeneration options on river floodplains in interior Alaska
Reforestation options for artificial regeneration of white spruce (Piceaglauca (Moench) Voss) were tested on three floodplain sites near Fairbanks, Alaska. Survival of containerized seedlings after outplanting was above 96%, regardless of harvest cutting method or mechanical site preparation, and declined little between the third and fifth growing seasons. Establishment and survival after direct seeding on seed spots was more variable and differed by harvest cutting method, by type of site preparation, and by the use of plastic seed shelters for seedling protection. Maximum terminal leader growth, seedling total height, and basal diameter were found on planted seedlings in clear-cut units on the better site. In clear-cut units prepared by blading on one site, basal diameter of seedlings five seasons after outplanting was almost 50% more than on similar surfaces in shelterwood units. Planted seedlings on unscarified surfaces and in small scalped patches generally had similar basal diameters. Results suggested that similar interior Alaska floodplain forests of white spruce can be successfully regenerated by using the clear-cutting harvest method and planting nursery-reared seedlings without mechanical site preparation.