All four major southern pines can be killed by the southern pine beetle, but loblolly and shortleaf are much more susceptible than longleaf and slash. Oleoresin from more than 50 trees of each species was tested for composition and amount of monoterpenes and resin acids, viscosity, flow (rate, duration, and amount), and rate of crystallization. Discriminant function analyses were used to classify the loblolly and shortleaf trees as to probable resistance. The best classification used physical properties (total flow, flow rate, viscosity, time to crystallization). Supposedly resistant and susceptible trees were subjected to controlled attack, and the chemical and physical properties of four loblolly pines that survived natural attack were measured. Resistance is strongly related to the physical properties of the oleoresin, and can be predicted by these properties. Loblolly and shortleaf trees with “average” properties usually succumb to 100 or more attacks per sq. m of bark surface. Several trees classified as resistant survived a much higher rate of attack.

Oleoresin viscosity, flow (rate, duration, and total amount), and rate of crystallization were determined for Pinuselliottii Engelm., Pinuspalustris Mill., Pinustaeda L., and Pinusechinata Mill, in central Louisiana, U.S.A. Physical properties of the oleoresin and tree morphological characteristics (diameter at breast height, growth rate, height, crown ratio, and age) were not strongly related in either of the four species. Pinuselliottii oleoresin was extremenly viscous, crystallized very slowly, and flowed at a slow rate over a long period, and total yield was moderate. Pinuspalustris oleoresin was of moderately high viscosity and very high yield and had a high rate of flow. Pinustaeda and Pinusechinata oleoresin had, on the average, low viscosity, a moderate to low total yield, a short duration of flow, and rapid rate of crystallization. A discriminant function analysis revealed that 19% of the Pinustaeda and 6% of the Pinusechinata trees had oleoresin properties more similar to Pinuspalustris and Pinuselliottii than to the means for their own species. This information is being used to assess tree susceptibility to attack by Dendroctonusfrontalis Zimm.

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Simple forest practice cost indexes, a weighted aggregate Southern Forest Practice Cost Index (SFPCI), and a Southern Forest Employee Wage Index (SFEWI) are developed. The SFPCI measures temporal changes in average costs of a fixed "operations basket" of southern forest practices. Each forest practices's relative contribution to the SFPCI are also calculated. General trends, and internal and external factors influencing cost index changes throughout time are examined in order to provide forestry managers insight for cost control measures. Simple cost indexes indicate all but two of the forest practices examined experienced cost increases from 1982 to 1988. The weighted aggregate SFPCI increased by 15% from 1982 to 1988, while the SFEWI increased by 19%; and inflation, as measured by the implicit Gross National Product price deflator, increased by 21%. In 1988, according to relative importance contribution values, forest practices associated with the establishment of new forestry crops accounted for 71% of total forest practice expenditures. South. J. Appl. For. 15(3):128-133.