EFFECT OF SIMULATED ACID-RAIN ON REPRODUCTIVE ATTRIBUTES OF RED SPRUCE (PICEA-RUBENS SARG)

Red spruce (Picea rubens Sarg.) growth and reproduction is declining in many areas of the eastern United States (Klein and Perkins, Bot. Rev. 54, 1-43, 1988). An often cited cause of this decline is air pollution. In this study simulated acid rain was used to examine the effects of low pH on the female reproductive structures of five red spruce trees showing no signs of pollution damage. Cone scale weight, seed weight, number of seeds per cone, and per cent germination of filled seed did not differ significantly among the acid rain treatments. The percentage of filled seed per cone was significantly reduced as the pH of the simulated rain solutions declined. © 1990.