Sap yield, sap sugar concentration, and sugar yield data from sugar maple trees collected over 3 years revealed great intra-and interseasonal variations. The effect of N, P, and K fertilizers, applied singly and in combination, affected the yield of sugar by affecting sap yield and/or sap sugar concentration. The combination fer-
A ranking system developed in east Texas classifies the susceptibility of host stands to southern pine beetle (Dendroctonous frontalis Zimm.) into four categories. Input variables include pine basal area per acre, average tree height, and a categorical evaluation of land form. Higher-hazard stands are generally overstocked, have taller trees, and grow on wet or low-lying sites. Management strategies are recommended for the various hazard categories.
Questionnaire responses from 26 schools involving 32 advanced level courses indicated close agreement on course goals with the major emphasis on forest soil properties in relation to management and silvicultural practices. Most respondents expressed a need for a forest soils text. Current reliance on outside readings does not seem to eliminate the need for a text. Great reliance is placed on field and laboratory work in support of lecture material. Laboratory facilities in the various institutions responding appear to be adequate. Although there is some variation among courses and in teaching methods, generally both seem to be of a traditional nature with little innovation. New techniques and approaches appear desirable, particularly in soil-site-management interpretations with increasing intensity of land use. Additional index words: Graduate courses, Graduate teaching, Forest soils education.
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