Height Growth of Loblolly and Slash Pine Plantations in the Northern Post-Oak belt of Texas
Abstract Age accounted for over 70% of the variation in tree height of 10- to 44-year-old loblolly pine (Pinus taeda L.) and slash (Pinus elliottii Engelm.) plantations established on deep sands, moderate sands, and nonsandy soils in the Northern Post-Oak Belt of Texas. Climatic and edaphicfactors, relating either directly or indirectly to the amount of moisture available for tree use, explained up to 17% of height growth variation. Height growth of the plantations was comparable to that of plantations growing in the pine-mixed hardwood forest cover type of East Texas. The NorthernPost-Oak Belt of Texas is an area approximately 50 to 100 miles wide located between the pine-mixed hard-wood forest type to the east and the black-land prairie to the west. Soils within the belt belong primarily to the Alfisol or Ultisol soil orders. The western-most areas of the belt receiveup to 20% less annual rain fall than the pine-mixed hardwood type of East Texas (U.S. Environmental Data and Information Service 1949-1982). The present forest of this area is dominated by post oak (Quercus stellata Wang.), black-jack oak (Quercus Marilandica Muench.), bluejack oak (Quercusincana Bartr.), and black hickory (Carya texana Buckl.) (Ward 1984). Loblolly pine (Pinus taeda L.) and shortleaf pine (Pinus echinata Mill.) occur naturally only in scattered locations (Wilson and Hacker 1986). South. j. Appl. For. 13(1):5-8.