Abstract Pinus resinosa from 50 different geographic-climatic seed sources ranging from Maine to Minnesota have been studied during a 25-year period in a plantation on the Kane Experimental Forest in northwestern Pennsylvania. Results showed only minor differences in survival and height growthup to 5 years of age, but there were small, significant differences for average total heights at 10, 20, and 25 years. Trees from seed sources from southerly latitudes had better height growth than those from the northerly latitudes. In spite of the statistical differences shown, red pineseed sources within the natural range are relatively uniform in development. For those on the Allegheny Plateau who have no local red pine seed source, certain Lake States seed-collection zones with climatic conditions comparable to those of the planting site will be good sources.
A. F. Hough (Thu,) studied this question.