Artificial frosting studies of radiata pine planting stock

Authors: D.A. Rook, M.I. Menzies, R.W. Rowbotham
Publication: New Zealand Journal of Forestry, Volume N.Z.J.For. 1974, Issue N.Z.J.For. 19(2) 1974, pp 295-300, Aug 1974
Publisher: New Zealand Institute of Forestry

Abstract: The frost tolerance of radiata pine seedlings and rooted cuttings was tested in winter (August) and spring (October) by simulating white frosts of — 3, — 6, and —10° C in a controlled climate room. Symptoms of injury were similar to those observed in the field. In general —10° appeared the critical winter temperature. Differences in frost tolerance were observed between seedlings raised in different nurseries, and rooted cuttings were more tolerant of winter frost than were seedlings. Cool-stored plants appeared to retain their frost tolerance at the time of lifting. The frosting technique and results described should prove useful for studying and screening for differences in frost tolerance.