Acrylic Resin Tubes for Studying Root Growth in Tree Seedlings

A new method was designed to study root growth of intact tree seedlings grown in acrylic resin tubes filled with soil

Effect of time and depth of planting on survival and growth of loblolly pine (Pinus taeda L.) seedlings in Texas

Loblolly pine seedlings were lifted from a nursery bed in two-week intervals (November 4-April 21) and were immediately planted in an open field. Each planting included seedlings planted at the root collar (A), one-half of shoot buried (B) and most of the shoot buried except for the one-inch terminal (C). Average mortality during the first year was 10%, 13% and 16% for the A, B and C planting depths, respectively; the corresponding values for the second year mortality were 2%, 3% and 5%. Average first year mortality by the planting periods ranged - 24% with the highest values for April plantings. Deep (C) planting produced most height growth during the first growing season and least during the second and third growing seasons

Cotyledon and Primary Needle Variation in Loblolly Pine From Mesic and Xeric Seed Sources

Cotyledons and primary needles in loblolly pines (Pinus taeda L.) of Bastrop County, Texas, provenance have morphological modifications which should tend to conserve moisture during drought. FOREST SCI. 23:33-36

Needle Variation in Loblolly Pine from Mesic and Xeric Seed Sources

Anatomical modifications in protective layers and stomatal characteristics of needles which would have moisture conserving effects were found in 2-yr-old seedlings of 1oblolly pines of the Bastrop County, Texas, provenance. Most of these modifications were absent from needles of 16-yr-old trees of the same provenance. Forest Sci. 20:88-90

Height. Growth of Loblolly and Slash Pine Plantations in the Northern Post-Oak Belt of Texas

Age accounted for over 70% of the variation in tree height of 1O- 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 edaphic factors, 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 Northern Post-Oak Belt of Texas is an area approximately 50 to 100 miles wide located between the pine-mixed hardwood forest type to the east and the blackland prairie to the west. Soils within the belt belong primarily to the Alfisol or Ultisol soil orders. The western-most areas of the belt receive up 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 stellate Wang.), blackjack oak (Quercus Marilandica Muench.), blue jack oak (Quercus incana 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

Site Factors Affecting Growth of Slash Pine in the Texas Post Oak Belt

A study was conducted in the Post Oak Belt of East Texas to determine which site factors affected height growth of slash pine (Pinus elliottii Engelm.). Height-age pairs were developed from stem analysis data. Nonlinear regression was implemented to develop a generalized height-age model. After curves were developed, stepwise regression was used to determine impacts of environmental variables on height growth. Environmental factors correlated with height growth included A horizon depth and those related to moisture relations including seasonal precipitation, average daily temperature, and texture of the A horizon. South. J. . Appl. For. 21(2):71-74