Too much rain can slow growth of container-grown pine seedlings

Authors: David B. South*, Tom E. Starkey
Publication: New Zealand Journal of Forestry, Volume N.Z.J.For. 2010, Issue N.Z.J.For. 55(3) 2010, pp 16-19, Nov 2010
Publisher: New Zealand Institute of Forestry

Abstract: Summary Observations over the past three decades indicate that waterlogged conditions in bareroot nurseries can adversely affect the survival of transplanted Pinus taeda L. seedlings. Waterlogged seedbeds can develop when frequent rains occur over an extended period of time. Anaerobic conditions may occur when warm soils remain saturated for just a few days. At some nurseries, problems occurred when rainfall exceeded 50 mm/week for a period of three weeks or more during the autumn. In 2009, data were collected that suggests this response also occurs in container nurseries. Rainfall during the autumn exceeded 151 mm during an 11 day period and this amount likely reduced seedling quality. Seedlings transplanted into sand exhibited complete mortality. However, if given a month to recover in a greenhouse, seedlings recovered. A similar detrimental effect from the saturating rain was not observed with Pinus palustris Mill.