Tracheid Length Research Articles

Intra-Ring and Inter-Ring Variations of Tracheid Length in Fast-Grown Versus Slow-Grown Norway Spruces (Picea Abies)

Our study was conducted on 40 Norway spruces [Picea abies (L.) Karst.] from a stand located in the Belgian Ardennes. Twenty trees were randomly sampled from a slow-growth category, and twenty others from a fast -growth category. The hypothesis under testing is fourfold: increased tree growth rate may affect 1) the intra-ring weighted frequency distribution of tracheid length, 2) the inter-ring variation (from pith to bark) of the parameters describing this frequency distribution, 3) the interring variation of the mean tracheid length, and 4) the correlation between yearly mean tracheid length and yearly ring width.

Age-age correlations for tracheid length and wood density in <I>Pinus sylvestris</I>

The existence of strong genetic correlations between traits at an early age and at an adult age should shorten the generation turnover of tree breeding populations and render forest tree breeding more effective. Genetic age-age correlations for tracheid length and wood density were estimated in Scots pine (Pinus sylvestris L.) and the efficiency of early selection for these traits was evaluated. Increment cores of 10-mm diameter were collected from trees of 106 full-sib families in a progeny trial located in southeastern Sweden and consisting of controlled matings between 30 parent trees. The additive genetic age-age correlations were consistently close to unity for all traits and ages studied. The additive genetic variance differed significantly from zero for all traits. The dominance variance was zero for tracheid length and small and insignificant for wood density. The heritabilities varied between 0.3 and 0.5. The genetic gain per year for both tracheid length and wood density was largest if selection was carried out at tree age 11, the lowest age studied, indicating that early tests for these traits will be efficient.

Tree/wood quality in slash pine following longterm cattle grazing

Tree height, diameter, and grade were measured on 14 cattle grazing trial plots located on the Palustris Experimental Forest in Louisiana's Kisatchie National Forest. These plots had been established in the early 1960s. Mensurational data was gathered on 28 trees from grazed sites and another 28 from ungrazed plots. Increment cores were also taken from these trees. Statistical analyses showed no effect attributable to grazing on any of the variables measured: tree height, tree diameter at breast height, tree grade, growth rate, amount of latewood, unextracted specific gravity, or tracheid length.

Growth rate effects on correlations among ring width, wood density, and mean tracheid length in Norway spruce (Picea abies)

The main hypothesis tested in this paper is whether heavy thinnings affect the correlations among ring width, wood density, and mean tracheid length. Within-tree correlations were calculated between time series of yearly measurements. Among-tree correlations were computed (1) between averages over a growing period and (2) year by year. Correlations were analyzed on 20 fast-grown and 20 slow-grown Norway spruces (Picea abies (L.) Karst.) from an even-aged, plantation-grown stand near Rendeux, Belgian Ardennes. In the within-tree approach, fast-grown spruces showed a stronger negative correlation between ring width and fiber length. In among-tree approach 1, the widely held negative correlation between ring width and wood density vanished when the spruce growth rate was above 2.2 cm/year in circumference. Among-tree approach 2 demonstrated that the magnitude and sign of the correlations also depended on the year; a few years showed a significant correlation between ring width and wood density for the fast-grown Norway spruces, whereas the correlation was systematically negative and significant on many years for the slow-grown spruces. This study may explain part of the contradictory results reported in the literature concerning hypotheses similar to ours.

Growth rate effects on correlations among ring width, wood density, and mean tracheid length in Norway spruce (<i>Picea abies</i>)

Growth rate effects on correlations among ring width, wood density, and mean tracheid length in Norway spruce (<i>Picea abies</i>)

Relationship between Wood Anatomical Properties and Specific Permeability of Sugi (Cryptomeria japonica) Sapwood and Intermediate Wood

The objective of this study was to clarify anatomical factors which determine specific permeability of sapwood and intermediate wood in air-dried sugi (Cr?~ptomeria juponica) wood. Superficial air permeability of sugi sapwood and intermediate wood was measured and then specific permeability was determined. Using these specimens for permeability tests, the proportion of latewood and earlywood, the percentage ol aspirated and incompletely aspirated pits, the number of bordered pits per tracheid, the number of tracheids per unit area and tracheid length were obtained. Specific permeability decreased with increasing levels in the stcm except for the lowest level and also related to distance from pith, suggesting that cambial age is related to specific permeability. A clear relationship between percentage ol latewood and specific permeability was not found, suggesting that effective pathways in earlywood determines permeability. Specific permeability of intermediate wood and sapwood were significantly related to the number of effective open pits in earlywood, Mi3J, which was determined by anatomical properties such as aspirated and incompletely aspirated pits, the number of pits and tracheids, and proportion of latewood, suggesting that specilic permeability of sugi sapwood and intermediate wood is a physical value determined by the intrinsic properties of earlywood in addition to the condition of bordercd pits.

Effect of radial increment core diameter on tracheid length measurement in Norway spruce

Effect of radial increment core diameter on tracheid length measurement in Norway spruce

Effect of radial increment core diameter on tracheid length measurement in Norway spruce

The effect of radial increment core diameter (comparing the effects of 12, 8 and 4 mm diameters, with sampling from chips used as a control) on the measurement of tracheid mean length and the percentage of broken tracheids was examined for mature wood of Norway spruce. Two methods of measuring tracheid length were used: image analysis, in which arithmetic mean length (AML) was calculated for unbroken tracheids, and the Kajaani FS-200, in which AML was calculated for all tracheids, regardless of damage. In addition to AML, length weighted mean length (LWML) was calculated for the Kajaani.

Biomechanical and hydraulic determinants of tree structure in Scots pine: anatomical characteristics.

The development of anatomical, hydraulic and biomechanical properties in Scots pine (Pinus sylvestris L.) stems aged 7 to 59 years was followed. The hydraulic diameter and length of tracheids increased with age to a maximum at 15 and 35 years, respectively. Number of tracheids per unit of sapwood area decreased with age to a minimum of 500-600 tracheids mm(-2). Variations in specific hydraulic conductivity and Young's modulus of stems were associated with variation in anatomical properties. Over the time sequence considered, hydraulic and mechanical properties were positively related to each other and followed a similar developmental pattern, with no suggestion of a trade-off between the two. For most of the tree's life-cycle, heartwood made only a small contribution to whole-section mechanical stiffness because of its location close to the flexural neutral axis, and because of the presence of juvenile wood.

Variation pattern of wood properties of naturalCunninghamia lanceolata

In this paper, the variation pattern of wood properties was studied for naturalCunninghamia lanceolata. The mathematical models of property parameters were obtained on tracheid length, microfibril angle, late wood percentage, growth ring width and growth ring density in the radial direction. The interrelation were analyzed between tracheid length and microfibril angle. The result can provide scientific theory basis for wood utilization and early prediction of wood properties.

Wood and bark anatomy of the African species of Gnetum

Quantitative and qualitative data are given for the two African species of Gnetum (Gnetum section Gnetum subsection Micrognemones). These species are lianoid and lack the fibre-tracheids of G. gnemon but have about the same vessel element and tracheid length as in that species. Vessel diameter is related to stem age and organography. Tori are clearly present in tracheary elements of the African Gnetum species, a first report for the genus. In these two species, origin of the lateral meristem, which produces vascular tissue and cambia, can be traced directly and indirectly to cortical parenchyma. A second kind of meristematic action, newly reported for Gnetum, is produced by proliferation of axial parenchyma, fragmenting secondary xylem. Both presence of tori and site of origin of lateral meristematic activity in Gnetum contrast with corresponding conditions in Welwitschia.

Basic Density, Tracheid Length and Strength Properties of Juvenile and Mature Wood ofPinus patulaGrown in Tanzania

SYNOPSIS More than 70% of Tanzanian plantations consist of conifers, 60% of which are Pinus patula plantations. Juvenile wood is one of the most important sources of variability. The proportion of juvenile wood in the stems of 27-year-old Pinus patula trees is considerable (weighted mean proportion of 49%). Juvenile wood has lower basic density, shorter tracheid length and inferior strength properties when compared to mature wood. Reporting average values does not give a true picture of differences existing between juvenile and mature wood, and this could lead to hazards.

Population variation in wood structure of white fir

Wood X-ray densitometry (inter- and intra-ring wood density, ring width) and measurements of tracheid length were used to evaluate wood structural variability in 93 trees from 33 populations of white fir (Abiesconcolor (Gord. et Glend.) Lindl.). Individuals from populations representing the geographic range of the species had been growing for 24 years in a plantation near Placerville, California. Growth ring widths showed a clinal increase from northern Oregon to southern Californian populations, due mostly to variations in width of the earlywood. Rates of change from pith to bark in tracheid lengths and earlywood density decreased from northern Oregon to southern California, with the highest rates of change being among Utah populations. Slower rates of change in tracheid length and wood density would contribute to more uniform wood structure in these southern populations. Multivariate analyses confirmed the separation of regional groups within white fir. Results indicated that there is a differentiation between northern and southern Californian white fir, consistent with the former being ascribed to A. concolor var. lowiana and the latter to A. concolor var. concolor. Arizonan populations were grouped with southern Californian white fir.

The Genetic Control of Ring Width, Wood Density and Tracheid Length in the Juvenile Core ofPinus patula

SYNOPSIS Controlled crosses were made between six Pinus patula Schiede & Deppe plus trees selected in plantations. Six full-sib families and two commercial checks were planted in randomised complete block thrice-replicated progeny tests at two sites in Zimbabwe. At 7,5 years, the tests were thinned and sample discs taken at breast height from six trees per plot. Ring width, basic density and tracheid lengths were assessed for each of rings 1 to 6, corresponding to years 2 to 7. All three traits were found to be under genetic control and the differences between the treatments were best expressed in the fourth year and on the harshest site. Genotype-environment interaction effects were absent for basic density and ring width but were pronounced for tracheid length. Juvenile-mature correlations were high for all three traits. Basic density was negatively correlated with ring width and tracheid length but ring width and tracheid length also tended to be inversely related. One generation of selection for vario...

Impact of spacing on tracheid length, relative density, and growth rate of juvenile wood and mature wood in Piceamariana

Ten 38-year-old trees of Piceamariana (Mill.) B.S.P., grown at each of three spacings (1.8 × 1.8, 2.7 × 2.7, and 3.6 × 3.6 m), at Stanley, 30 km west of Thunder Bay, Ont., were used to study the impact of spacing on growth rate, relative density, and tracheid length of juvenile and mature wood. Increment cores of 12 mm diameter were extracted from the south aspect of each tree at breast height. The boundary of juvenile and mature wood was demarcated by the variation in tracheid length, which varied among trees from ring 11 to 21. Average growth rate, relative density, and tracheid length were obtained between the pith and boundary point (juvenile wood) and beyond the boundary point (mature wood). Differences between the levels of spacing for the three response variables in both juvenile and mature wood were tested using contrasts. Properties of juvenile and mature wood were found to be affected differently by the plantation spacing. Juvenile wood has a faster growth rate and shorter fibres than mature wood. Relative density was similar in both wood zones. The growth rate in juvenile wood was found to be significantly different among the spacing levels. For mature wood, only the growth rate at the 3.6 × 3.6 m spacing was significantly different from the other two spacing levels. The highest relative density, 0.39, in both juvenile and mature wood was found at the 1.8 × 1.8 m spacing. No significant difference in the relative density between the two wider spacings was observed. At the widest spacing, the relative density was 8% lower than that at the 1.8 × 1.8 m spacing. The longest fibre lengths were found at the intermediate 2.7 × 2.7 m spacing, 2.05 mm in juvenile wood and 2.94 mm in mature wood. Tracheid lengths of the 3.6 × 3.6 m spacing were significantly shorter than those of the other two spacings. The relative density and tracheid length of plantation grown wood were lower than those of natural grown wood by at least 5% for relative density and 33% for tracheid length.

Tumor Wood Anatomy in Korean Red Pine (Pinus Densiflora)

The anatomy of tumor wood and normal wood in a branch of Korean red pine (Pinus densiflora S. et Z.) is compared. In tumor wood the tracheids and rays are irregularly arranged, the cell lumina contain resinous substances and fungal hypha, the tracheid files are of variable width within the growth ring, and traumatic vertical resin canals are present. There are also differences in length of tracheids, numbers of vertical and horizontal resin canals (fusiform rays), height of fusiform rays, and number and height of uniseriate rays. The modified structure of the tumor wood originates near the pith. The wider growth rings, considerably shorter but not wider tracheids, and larger and more numerous rays in tumor wood are associated with a higher radial growth rate, which in turn results in the externally massive wood tumor.

Basic density, longitudinal shrinkage and tracheid length of juvenile wood ofPicea abies(L.) Karst

Variation in the growth ring width, basic density, longitudinal shrinkage and tracheid length was investigated in the juvenile wood of Norway spruce samples taken from different heights in the stem. Annual height increments were cut from the ten youngest shoots from trees of three different heights. By this method the properties of an individual growth ring could be analysed without taking samples from each ring. Sixteen tree tops of an average stem height of 8, 15 and 25 m were analysed. Basic density was low in the first shoot, highest in the second or third one and decreased gradually thereafter. Longitudinal shrinkage was highest close to the pith and decreased to about 0.2% in the outer rings. Tracheids were only ca. 1 mm long close to the pith and their length increased sharply towards the tenth shoot. The properties of juvenile wood varied with the height in the stem. Longitudinal shrinkage around the pith seemed to increase with increasing height and basic density was highest at 25 m stem height. ...

Maturation in larch: age-related changes in xylem development in the long-shoot foliage and the main stem.

As the meristems of eastern larch (Larix laricina (Du Roi) K. Koch) mature, they produce long-shoot foliage with progressively higher chlorophyll content and net photosynthesis and progressively lower specific leaf area (Hutchison et al. 1990). Despite the apparent increase in foliar vigor, both shoot height and diameter growth rates declined during maturation. These changes were associated with changes in xylem morphology of the vascular tissue of both the long-shoot foliage and the main stem. Although the number of xylem cells remained constant in a cross section of the foliage, their diameters increased with age. With increasing maturation, the same number of xylem cells were produced per radial file in the annual rings of the main stem, but their radial diameters decreased, which accounted for the decrease in diameter growth. There was no change in tracheid length during maturation. We conclude that the decrease in growth rate with increased maturation is not due to a decrease in physiological vigor of the foliage, but is a function of reduced sink strength of the growing shoots.

Variation in crushing strength and some related properties of a red pine

Below-crown radial and height variations in maximum crushing strength parallel to grain, relative density and tracheid length of an immature, 55 year old, red pine were studied. All properties showed pronounced trends with radial age and increased from pith to bark. A radial age of 16 years was estimated as the ‘age’ from which mature stem wood is formed. All properties studied varied with height above ground. Strong correlations were observed among properties. The study tree exhibited noticeably lower average crushing strength than is reported in the literature for wood from mature red pines.

Growth and Wood Properties in a Carolina Sandhills Pine Seed Source Study

Abstract Eight pine sources were planted on a sandhills site in South Carolina. Total height, dbh, wood specific gravity, tracheid length, and fusiform rust (Cronartium quercum [Berk.] Miyabe ex. Shirai f. sp. fusiforme) infection were evaluated following 17 growing seasons. The Choctawhatcheesource of sand pine (Pinus clausa [Chapm.] Vasey) is apparently well adapted to the deep sands of the Carolina sandhills and exhibited superior height and diameter growth to slash pine, two local sources of loblolly pine (P. taeda L.), and two sources of Virginia pine (P. virginiana Mill.). A combination of excellent growth and reasonable survival resulted in significantly more cubic foot volume per acre than the other seed sources or species included in this study. Despite having the lowest weighted specific gravity of all sources in this planting, the Choctawhatchee sand pineproduced more than twice as much dry weight per acre than any other source. A single open-pollinated family of drought-hardy loblolly pine from Bastrop County, TX, displayed excellent growth, survival, rust resistance, and wood quality. Its performance warrants a more careful and wider evaluationof this seed source for use on these difficult sandhills sites in the Carolinas. South. J. Appl. For. 16(4):164-169