Watt, Richard F.2010-02-082010-02-081961-04-15Watt, R.F., (1961), "Artificially Extended Photoperiod Increases Size of Nursery Stock", Minnesota Forestry Notes 104, School of Forestry, University of Minnesota0099-4332https://hdl.handle.net/11299/57313Published as Scientific Journal Paper Series No. 4585 of the Minnesota Agricultural Experiment Station.en-USforests and forestryMinnesotaresearchReport