Growth correlations of cottonwood clones developed from mature wood cuttings
1977
Randall, W.K.
Cuttings were taken from 24 mature trees of cottonwood (Populus deltoides) in stands in W. central Mississippi in 1963. The resulting plants were used as the source of cuttings for a field trial in 1965. Diam. and ht. were measured over the next 8 yr; total stem vol. was measured at 5 yr of age, when the trees were thinned. Heritability was greater for diam. than for ht. Genotypic and phenotypic correlations of 8-yr diam. and 5-yr vol. with diam. and ht. at various ages increased as the trees aged. Selection of the pairs of clones with the greatest 8-yr diam., 7-yr ht. and 5-yr vol. gave genotypic gains over the mean of 17, 8 and 40% respectively. Ranking the clones for diam. at each age indicated that, in agreement with an earlier study [see FA 33, 5830], the fastest-growing clones could be selected after only 1-3 yr.
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