Bole girdling affects metabolic properties and root, trunk and branch hydraulics of young ponderosa pine trees.

Effects of trunk girdling on seasonal patterns of xylem water status, water transport and woody tissue metabolic properties were investigated in ponderosa pine (Pinus ponderosa Dougl. ex P. Laws.

Storage versus substrate limitation to bole respiratory potential in two coniferous tree species of contrasting sapwood width.

Two coniferous tree species of contrasting sapwood width (Pinus ponderosa L., ponderosa pine and Pseudotsuga menziesii Mirb., Douglas-fir) were compared to determine whether bole respiratory potential was correlated with available storage space in ray parenchyma cells and/or respiratory substrate concentration of tissues (total nitrogen content, N; and total non-structural carbohydrate content, TNC).

Stem respiratory potential in six softwood and four hardwood tree species in the central cascades of Oregon.

Mature and old growth trees of varying sapwood thickness were compared with regard to stem respiration. An increment core-based, laboratory method under controlled temperature was used to measure tissue-level respiration (termed respiratory potential) of ten different tree species. Bark (dead outer and live inner combined), sapwood, and heartwood thickness measurements were used to predict sapwood volume from stem diameter (including bark) for four of the ten species.

Thigmomorphogenesis: changes in the morphology and mechanical properties of two Populus hybrids in response to mechanical perturbation.

To identify hybrid-specific differences in developmental response to mechanical perturbation (MP), we compared the effects of stem flexure on several morphological and mechanical properties of two Populus trichocarpa Torr. & A. Gray x P.

Thigmomorphogenesis: a dose response to flexing in Ulmus americana seedlings.

Six-week-old half-sib seedlings of Ulmus americana L. were subjected to different amounts of flexure daily for 3 weeks under controlled greenhouse conditions. The daily flexure treatments were: no flexing in a staked stem, minimal flexing in a non-staked stem, and five, 10, 20, 40, and 80 flexures.

Within-stem variation of respiration in Pseudotsuga menziesii (Douglas-fir) trees.

•  A technique for measuring in vitro respiration was investigated to understand why rates were higher than those reported in vivo and to elucidate trends within mature Pseudotsuga menziesii (Douglas-fir) trees. •  Extracted increment cores were divided into 3-4 radial depths and a gas chromatograph was used to compare respiration rates radially and vertically within stems. •  Respiration of inner bark was 2-3 times greater than sapwood, and 50-70% higher in outer than inner sapwood.

Respiratory potential in sapwood of old versus young ponderosa pine trees in the Pacific Northwest.

Our primary objective was to present and test a new technique for in vitro estimation of respiration of cores taken from old trees to determine respiratory trends in sapwood. Our secondary objective was to quantify effects of tree age and stem position on respiratory potential (rate of CO2 production of woody tissue under standardized laboratory conditions). We extracted cores from one to four vertical positions in boles of +200-, +50- and +15-year-old Pinus ponderosa Dougl.