Chemical and Environmental Treatments Promoting Rooting of Pine Cuttings

Abstract

Cuttings from older pines rooted more abundantly and rapidly in a growth chamber than in a greenhouse. Numerous rooting powder formulations were tested, and those containing auxins, sucrose, a fungicide, and a growth retardant outperformed those lacking one or more of these components. Best treatment combinations gave 83% rooting of cuttings from 13-year-old shortleaf pine (Pinusechinata Mill.) in 12 weeks, 100% rooting of cuttings from 12-year-old Japanese black pine (P. thunbergiana Franco) in 8 weeks, and 100% rooting of cuttings from 1-year-old slash pine (P. elliottii var. elliottii Engelm.) in 6 weeks. The most effective powder contained 1% each of indolebutyric acid, 1-phenyl-3-methyl-5-pyrazolone, and N-dimethylaminosuccinamic acid, plus 10% each of powdered sucrose and captan.