Effects of Extended Photoperiod on Southern Rocky Mountain Engelmann Spruce and Douglas-fir
Four sources of Engelmann spruce and two of Douglas-fir were grown under eight different extended photoperiod regimes. Incandescent light 1 minute of every 15 at night at 270 lux was more effective than continuous incandescent at 1200 lux or intermittent fluorescent at 950 lux at preventing bud dormancy and maintaining continuous height growth.
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Author(s): Richard W. Tinus
Publication: Tree Planters' Notes - Volume 32, Number 4 (1981)
Section: General
Volume: 32
Number: 4