Weinrich wrote that while Bell " et al . " had a " more than adequate sample size ", the sample had at times been broken down into smaller groups, and some of the conclusions about those groups had to be considered tentative.
32.
To help apply " free-to-grow " regulations in British Columbia and Alberta, management guidelines based on distance-dependent relations within a limited radius of crop trees were developed, but Lieffers et al . ( 2002 ) found that free-growing stocking standards did not adequately characterize light competition between broadleaf and conifer components in boreal mixedwood stands, and further noted that adequate sampling using current approaches would be operationally prohibitive.
