SummaryOf three environmental variables affecting black walnut seedling establishment, moisture stress overshadowed the effects of fescue leachate and fertilizer. Interactions between moisture stress and family and between fescue leachate and moisture stress for both seedling height and dry weight suggested that selection for tolerance to moisture stress is possible, whereas progress from selecting for resistance to rescue leachate would be difficult. Family response to high moisture stress resulted in reductions of 17 to 33 percent in height and 36 to 48 percent in dry weight when compared with seedlings grown under moist conditions. The only effect of fertilization was a 9 percent decrease in seedling survival under high moisture stress conditions.
Fifteen seed sources of black walnut were planted at Manhattan, Kansas (39.2°N and 96.5°W) in 1967, the western edge of its natural range. After 22 years, height, dbh, and survival measurements revealed that local trees (Kansas) and trees from within 200 miles south of the planting site grew tallest. Height and dbh correlations were highly significant and increased when compared to successive 5-yr interval measurements. Geographic and climatic variables of seed sources did not provide a significant predictive regression model. Low survival limited the success of some sources, such as two from Indiana, in this Kansas plantation. North. J. Appl. For. 9(2):41-43.
In a 37-year-old southern Illinois species comparison/provenance test shortleaf pine produced greater volumes of wood than loblolly pine, both per acre and per/acre/year. Although surviving loblolly pine were taller, shortleaf pine had greater per/acre volume primarily due to a two-fold greater survival than that for loblolly pine. Only 14% of the loblolly pine were present at age 37, partially reflecting a biased representation with southern seed sources. For shortleaf pine, trees of southwest Missouri had the highest survival and the greatest production per acre. North. J. Appl. For. 5:155-158, June 1988.
A black walnut (Juglansnigra L.) provenance–progeny test was established on four widely separated sites, with seedlings grown at two nurseries to contrast the effects of site, seedling size, and genotype. Five years after establishment, site and genotype effects continued to be large while the nursery effect, although statistically significant, was diminishing in importance. Therefore, seedling size resulting from cultural nursery manipulation is not as important as proper geographic seed origin or site selection.
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