We studied an abandoned field in southern Indiana to determine whether planted hardwood growth differed according to vegetation. We also wanted to determine if these growth differences were associated with differences in physical, chemical, and biological soil conditions. Our results reveal that growth of planted hardwoods is strikingly different for areas that had supported some kind of tree cover since abandonment. These growth differences were associated with foliar nitrogen, and with several physical, chemical, and biological soil factors. We attribute the striking growth differences to the combined effect of soil conditions that have been improved by many years of tree cover present on abandoned agricultural land.

This manual is directed toward the evaluation and classification of forest land in north-west Ontario for timber production, with the primary objective of providing tools for a quantitative evaluation of the capability of forest land to produce tree growth. The first few chapters describe methods for estimating forest site quality, including direct methods based on measuring site index from standing trees and indirect methods based on soil and topographic features. The manual also provides a complementary framework showing relationships between site quality, forest-landscape classification, and growth and yield. This framework accommodates other land values that are in addition to timber production. A final chapter suggests how application of this integrated framework can produce a diversified forest landscape having a spectrum of management intensities, a variety of site-specific silvicultural practices, and a variety of forest land values and uses.