Consistency of Cone Production in Individual Red Pine

Abstract

A plantation of red pine (Pinus resinosa Ait.) produced heavy cone crops in 1970 and 1984. Established at 6.5 × 6.5 m, the stand was 18-years old in 1970 and still open-grown; crowns were closed before 1984. Cone production at the two dates was compared for 28 trees. While total production was similar for 1970 and 1984, distribution within the sample differed. Although 18% of the trees maintained their rank in 1984, some large changes in production ranking took place from one crop to the next. Despite a tendency at both dates for crop size to increase with current dbh, exceptions were evident and the largest trees did not necessarily bear the most cones. Crop size in 1970 was the variable most closely associate with 1984 crop size and was significantly correlated with it independently 1984 dbh. High cone production did not seem to depress tree growth, based on a comparison of 1970-72 basal area increment of more versus less prolific cone bearers. Before a stand has borne its first good cone crop, expectations for highest yields would have to be based on tree size. For subsequent crops, previous production by individuals would be the best guide. The two top cone bearers far surpassed all others in both crop years and would be the first individuals selected for seed trees in a seed production area.