Separate analyses were done for Experiment 1, which examined the effects of
seed source and P level, and for Experiment 2, which examined the effects of soil
type and P level. The repeated measures analysis option in SAS Proc Mixed
was used with age as a covariate to determine the significance of treatment
effects and their interactions on each of the koa response variables. Because
differences in growth during the first 6–12 months after planting were small,
to simplify analysis only the data for the 12–36 month measurements were
used, except in the case of analyses of branchiness, in which only the data
for 6–12 months after planting were used. The log transformation was used on
height, basal diameter, dbh, branchiness, crown volume, andwood biomass data
before analysis. The arcsine transformation was used on survival data before
analysis. Type 3 tests for fixed effects were used for determining equality of
slopes for seed source, soil type, and rate of P fertilization. Least-square means
were back transformed for presentation of results. SAS Proc GLM was used
to examine effects of treatments at 12 months after planting on foliar nutrient
concentrations. Because the tallest plants were assigned to block 1 and the
shortest ones to block 4, block was a fixed rather than a random effect. Pairwise
comparisons of treatment means at 36 months (12 months for branchiness) after
planting were performed using Tukey’s HSD test and α = 0.05.
Separate analyses were done for Experiment 1, which examined the effects of
seed source and P level, and for Experiment 2, which examined the effects of soil
type and P level. The repeated measures analysis option in SAS Proc Mixed
was used with age as a covariate to determine the significance of treatment
effects and their interactions on each of the koa response variables. Because
differences in growth during the first 6–12 months after planting were small,
to simplify analysis only the data for the 12–36 month measurements were
used, except in the case of analyses of branchiness, in which only the data
for 6–12 months after planting were used. The log transformation was used on
height, basal diameter, dbh, branchiness, crown volume, andwood biomass data
before analysis. The arcsine transformation was used on survival data before
analysis. Type 3 tests for fixed effects were used for determining equality of
slopes for seed source, soil type, and rate of P fertilization. Least-square means
were back transformed for presentation of results. SAS Proc GLM was used
to examine effects of treatments at 12 months after planting on foliar nutrient
concentrations. Because the tallest plants were assigned to block 1 and the
shortest ones to block 4, block was a fixed rather than a random effect. Pairwise
comparisons of treatment means at 36 months (12 months for branchiness) after
planting were performed using Tukey’s HSD test and α = 0.05.
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