In 1969, 1-year-old black cherry (Prunusserotina Ehrh.) seedlings from 21 to 33 provenances were planted at each of four locations in the northeastern United States. After 10 growing seasons, survival at each plantation was related to the latitude of the seed source. Differences in height among provenances were not correlated with the latitude of the seed source. Provenance × plantation interaction for height was large, as were differences in mean height among plantations. Differences in leaf characteristics were associated with the location of the seed source, but the pattern of variation in stem form was random rather than regional.
Yellow-poplar seed-heads can be collected successfully by shaking using a standard Shock Wave Shaker. In the first year of this trial the average percentage shaken was 64 per tree, varying from a low of 24 to a high of 95. Average percent shaken dropped to 49 per tree the second and third years, with a range from 9 to 90%. Shaking causes superficial damage only and will not affect subsequent crops. There seemed to be no effect due to tree size, seed-head size, or shaking time. Pre-collection estimates of numbers of seed-heads using field glasses to aid in counting were only minimally successful. North. J. Appl. For. 4:78-81, June 1987.
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