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Experiment demonstrated significant height growth increase with foliar sprays in white pine seedlings, suggesting effective growth enhancement.
Two-year-old white pine seedlings were sprayed one, two, or three times with 1- or 2- percent gibberellic acid and grown in photoperiods of 14 or 16 hr. Height growth increased significantly with additional foliar sprays, but was not affected by gibberellic acid concentrations or photoperiod. Forest Sci. 18:196-197.
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Jensen et al. (1972) studied this question.
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