Loblolly pine (Pinus taeda L.) and shortleaf pine (Pinus echinata Mill.) have widely overlapping geographic ranges. Hybridization between the two species has interested tree breeders for a long time. Morphologically, the two pine species are different. The needles of loblolly pine are 6 to 9 inches long, usually with three yellow-green needles per fascicle; but shortleaf pine needles are 3 to 5...

In a three year study, IOOderate and severe root pruning just before planting was compared to no root pruning, on two size classes of seedlings (smaller and larger than average). Seedlings were bar planted in holes the full depth of the planting bar blade. For the smaller seedlings, survival was 1.0 percentage point higher for moderate pruning and 5.6 points lower for severe pruning compared to...

The influence of extractive content on the thermal stability and kinetic degradation of two wood species has been investigated using chemical analysis and thermogravimetry. Two wood species were studied: Pinus taeda and Eucalyptus grandis. Thermogravimetric results showed that higher extractive contents in the wood accelerate the degradation process and promote an increase in the conversion val...

A reference karyotype is presented for loblolly pine (Pinus taeda L., subgenus Pinus, section Pinus, subsection Australes), based on fluorescent in situ hybridization (FISH), using 18S-28S rDNA, 5S rDNA, and an Arabidopsis-type telomere repeat sequence (A-type TRS). Well separated somatic chromosomes were prepared from colchicine-treated root meristems, using an enzymatic digestion technique. S...

Pine forests throughout the world are subject to disturbance from tree-killing bark beetles, but pine species differ in their susceptibilities. In the southeastern United States, Pinus palustris Mill. suffers far less mortality from the southern pine beetle, Dendroctonus frontalis Zimmermann, than do its sympatric congeners. We tested the commonly invoked hypothesis that P. palustris has relati...

We quantified nitrogen (N), phosphorus (P), potassium (K), calcium (Ca) and magnesium (Mg) content, use (nutrient amount for one growth year), retranslocation (nutrients recycled before foliage senescence), uptake (use minus retranslocation), volume production per unit of uptake and fertilizer-uptake efficiency (percent applied taken up) in a 2 x 2 (nutrient and water) factorial experiment repl...

This paper reports on a long-term thinning study established in stands of naturally seeded loblolly (Pinus taeda L.) and shortleaf (P. echinata Mill.) pine in southern Arkansas and northern Louisiana. Plots were established in 1949–50 and 1954 in previously unmanaged stands, thinned about once every 5 years from age 20 to 60 years (40 years of active cutting, to 1990). The study was discontinue...

A Pestalotiopis sp. was isolated from the trunk bark of Pinus taeda. The fungus was cultivated in liquid medium and produced three highly oxygenated caryophyllene sequiterpene derivatives, named pestalotiopsolide A, taedolidol and 6-epitaedolidol, respectively. The sesquiterpenes were isolated by silica gel based chromatographic procedures and their structures were elucidated by NMR spectroscop...