Tracheid Length Research Articles

Comparative Wood Anatomy of Southern South American Cupressaceae

The wood anatomy is described for the Cupressaceae indigenous to southem South America: Austrocedrus chilensis, Pilgerodendron uviferum and Fitzroya cupressoides. The abundance and distributional pattern of axial parenchyma within each annual ring, height, and the presence or absence of nodules in the end walls of ray parenchyma are all useful anatomical features for distinguishing between the three species. Physical characteristics such as odour and heartwood colour also can be used to separate these species. Axial parenchyma cell length and tracheid length show considerable interspecific variation. Tracheid lengths of Pilgerodendron, but not of Austrocedrus and Fitzroya, decrease with increasing latitude.

Variation of Wood Structure and Properties of Cupressus Sempervirens Var. Horizontalis in Natural Populations in Greece

The variation of specific gravity, ring width, tracheid length and tracheid crosssectional dimensions was studied among the remote natural forests of Cupressus sempervirens var. horizontalis Gord. of the Greek islands Crete, Rhodes and Samos.

Radial Variation and Growth Rate in the Length of the Axial Elements Of Sessile Oak Wood

Radial variability of the axial element length in oak-wood is most prominent in the juvenile wood which inc1udes approximately 30 annual rings. The length of fibres, tracheids and vessel elements increases from the pith outwards according to a second degree curve. This dependence is most apparent for wood fibres, whereas it is the least distinct for vesseI elements. In the mature zone, anatomical elements are, on average, 10 to 20% Ion ger than in juvenile wood. With deteriorating conditions of tree growth, the length of the anatomical elements tends to increase. There is a negative correlation between length of the measured elements and growth ring width; this is most c1early so for fibres. A similar relationship exists between the length of anatomical elements and wood density.

Growth, dry weight partitioning and wood properties of Pinus radiata D. Don after 2 years of CO2 enrichment

Abstract Advanced selections (families 20010 and 20062) of P. radiata D. Don were exposed to either 340 or 660 μmol CO2 mol 1 for 2 years to establish if growth responses to high CO2 would persist during the development of woody tissues. The experiment was carried out in glasshouses and some of the trees at each CO2 concentration were subjected to phosphorus deficiency and to periodic drought. CO2 enrichment increased whole‐plant dry matter production irrespective of water availability, but only when phosphorus supply was adequate. The greatest increase occurred during the exponential period of growth and appeared to be tied to increased rates of photosynthesis, which caused accelerated production of leaf area. The increase in whole‐plant dry matter production was similar for both families; however, family 20010 partitioned larger amounts of dry weight to the trunks than family 20062. which favoured the roots and branches. Wood density was generally increased by elevated CO2 and for family 20010 this increase was due to thickening of the tracheid walls. Tracheid length was similar at both CO2 levels but differed between families. These results suggest that, as the atmospheric CO2 concentration rises, field‐grown P. radiata should produce more dry weight at sites where phosphorus is not acutely deficient, even where drought limits growth; however, increases in wood production are likely only for genotypes which continue to partition at least the same proportion of dry weight to wood in the trunk.

Tracheid Length in Vital and Non Vital Douglas Fir (Pseudotsuga Menziesii) in the Netherlands

Tracheid length in relation to growth ring width is recorded for five Douglas firs from different sites in the Netherlands. The investigated trees differed in vitality assessed by crown appearance. Non vital trees showed a growth reduction which coincides with a decrease in tracheid length. Temporary growth reductions in vital trees did not result in a decrease of tracheid length. The relations hip between tracheid length and ring width is discussed.

Wood Property Variation in SixPinus radiata(D. Don) Trees Grown in the Jonkershoek State Forest

SYNOPSIS The sources of variation, their relative contribution to the total and random variation, and the general pattern of variation were investigated for total ring width, latewood width, latewood percentage, grain angle, basic density and fibre length. For the purpose of this study, six trees, 41 years of age, were selected in the Jonkershoek State Forest. All six wood properties exhibited significant variations that could be related to ring number. However, for ring width, latewood percentage and density this variation was dependent on height in the tree. Strong tree x ring interactions were also found for latewood percentage, tracheid length and grain angle suggesting that the effect of ring number is different from tree to tree. Significant variations that could be related to height in tree were also found for all properties except grain angle. For all properties the variation pattern was independent of trees. Between-tree differences were highly significant for all wood properties except tracheid ...

Relation between the permeability and the anatomy of jack pine sapwood with stand development

The anatomical characteristics of sapwood from the base of the live crown of trees from 11 jack pine stands (Pinusbanksiana Lamb.) of different age and site quality were related to the patterns of change of longitudinal sapwood permeability (k) previously observed to occur among these stands. Tracheid length (Lt) increased rapidly from a minimum of 1.9 mm to a plateau of around 3.6 mm as stand age and site quality (productivity class) increased. Sapwood relative water content (Rs) measured before saturation ranged from 78 to 85% for the majority of trees. Samples taken from trees growing on poor sites, however, exhibited significantly lower values of Rs, which probably resulted in their remaining below saturation during the determination of sapwood permeability. The lower Rs values were assumed to be reflective of more adverse water balances during the growing season associated with rapidly drained and (or) shallow soils. Tracheid lumen diameter (Dl) was positively correlated with k within age-classes 15 and 35, but not thereafter. The initial relation between Dl, and k is thought to be associated with corresponding increases in the area of pit membranes, which determines the number of pores within a pit membrane. Values of k were never more than 60% of the values calculated by Poiseuille's law for ideal capillaries (kc) and were generally less than 40%. Values of k tended to approach kc with increasing Lt and decreasing Dl. Overall, Poiseuille's law by itself could not explain the changes in the hydraulic properties of jack pine sapwood with stand development. However, Lt and Rs could together account for 72% of the variation in k. Young stands that had different k depending on site quality generally had corresponding differences in Lt, Rs, and (or) Dl. Mature stands that had reached maximum k on all quality sites no longer showed differences in Lt, Rs, or Dl.

Distribution, Size and Effective Aperture Area of the Inter-Tracheid Pits in the Radial Wall of Pinus Radiata Tracheids

The distribution, size and effective aperture area of inter-tracheid pits were studied in a 29-year-old plantation-grown tree of Pinus radiata by means of light and electron microscopy. It was found that the number of pits per tracheid in the first ten years is related more to tracheid length than to the age of the wood. Beyond the tenth year, the number of pits per tracheid is mainly related to the age of the wood, regardless of tracheid length. In addition, there is a positive linear relationship between tracheid diameter and pit diameter, indicating that the larger tracheids contain larger pits. The percentage of the effective aperture area per mrn length of radial tracheid wall is discussed, in relation to the 'percentage of aspirated pits and total area of pit aperture per tracheid.

Effects of fertilization on wood density and tracheid length of 70-year-old lodgepole pine in west-central Alberta

Fertilization with nitrogen, phosphorus, and sulfur had relatively minor and overall negligible effects on both basic wood density and tracheid length of 70-year-old lodgepole pine (Pinuscontorta Dougl. var. latifolia Engelm.) on both Coalspur and Mercoal soil types in west-central Alberta. Wood density declined moderately 1–5 years after treatment on both soil types, but the decrease was offset by an increase in density 6–10 years after fertilization. Tracheid length of the pine decreased moderately after fertilization; high sulfur levels were generally associated with greater decreases in tracheid length.

Cyclophytic effects on wood structure in Pinusradiata D. Don. II. Tracheid morphology

The effects of apical ontogeny on xylem morphology in Pinusradiata were examined in grafted trees and in clonal pairs of trees grown from cuttings from hedge- and tree-form donors (H and T). At the time of sampling the grafted rootstocks were 21 years old, and trees from H and T plants were 11 years old from the date of planting rooted cuttings. In grafted trees tracheids were longer, and the rate of increase in tracheid length was greater above the graft. Since growth rings were narrower above the graft, the difference in rate of increase in tracheid length above and below the graft was greater when plotted against distance from pith than against growth ring number. In comparisons of H and T plants, T plants (expected to be at a later stage of apical ontogeny) produced fewer but longer and wider tracheids. Cell wall volumes per tracheid were greater in T plants, but because the tracheid diameters in H plants were smaller, wall volumes per unit tracheid volumes were consistently greater in H plants. The role of apical ontogeny in explaining patterns of anatomical variation within the stem is discussed. H and T plants of radiata pine were from the three mainland populations: Año Nuevo, Monterey, and Cambria. The Año Nuevo population produced the greatest numbers and the largest tracheids. The Monterey population had the shortest tracheids amongst H plants, but their tracheid lengths were equal to those of the Año Nuevo population in T plants.

Wood Anatomy of Drimys S.S. (Winteraceae)

Qualitative and quantitative data are reported for seven specimens representing six varieties of the four species of Drimys generally recognized. Tracheid length and diameter are correlated both with plant size and with severity of climate: wide, long tracheids, not fluctuating in diameter seasonally, occur in Drimys of moderate elevations in subtropical latitude; narrower, shorter tracheids, becoming radially narrower briefly in latewood, occur in Drimys from higher altitudes and latitudes. Vesturing (warty layer) on the inside surface of tracheids occurs in Drimys from latitudes and altitudes where appreciable freezing is to be expected, but vesturing is absent at lower elevations and latitudes. Vesturing may bond water to tracheid walls better so that water columns do not break under high tensions produced by such conditions as transpiration when soil remains frozen. Scalariform pitting on end walls of Drimys tracheids occurs during the first year (metaxylem), but is replaced by alternate circular pits later; injury to the cambium, even of a mild kind, results in reversion to sca1ariform end wall pitting. Tracheid wall thickness is not correlated with tracheid diameter. Tracheid-ray pits are 75% the diameter of tracheid-tracheid pits. Axial parenchyma is sparse and diffuse (occasionally cells in tangential or radial pairs). Rays are Heterogeneous Type I; ray cells commonly have bordered pits on tangential walls. Silica bodies are reported (first report for Winteraceae) in rays of three collections of Drimys.

Características tecnológicas de Pseudotsuga menziesii creciendo en Valdivia

SUMMARY This study analizes some of the physical and mechanical properties of Douglas-fir trees from three stands located on the coast of the province of Valdivia, Chile. Specific gravity, skrinkage, tracheid length, compression parallel to grain, static bending, hardness Janka and nail withdrawal were determined. Average test results and their variability show a high similarity with species growing in the middle west of the United States.

Geographical variation in wood properties of Larixlaricina juvenile wood in northern Ontario

Growth rate, latewood ratio, specific gravity, and tracheid length of Larixlaricina (Du Roi) K. Koch juvenile wood were studied with two 12-mm increment cores extracted at breast height from 240 healthy trees from 12 locations at a range in latitude from 46 to 56° N in northern Ontario. Ten trees were selected from each stand and two stands were chosen from each location. Univariate analyses of variance indicated that growth rate and latewood of juvenile wood varied significantly in various locations, stands, and trees at the α = 0.01 level of significance. Growth rate of juvenile wood decreased from a lower latitude to a higher latitude, whereas latewood ratios displayed a reverse trend, i.e., a higher latewood ratio was found at a higher latitude. Specific gravity of juvenile wood varied significantly in individual trees. Tracheid length varied significantly among locations, stands, and trees. The overall average growth rate, tracheid length, and specific gravity are 1.29 mm per ring, 2.10 mm, and 0.43, respectively. An unexpected relationship was found between growth rate and tracheid length. Growth rate of juvenile wood has a positive relationship with tracheid length and an inverse relationship with specific gravity.

Variations in tracheid length and morphological changes in tracheid tips associated with the development of compression wood

Variations in tracheid length and morphological features of tracheid tips within a growth ring associated with the development of compression wood were observed in young trees of Larix leptolepis Gord. and Abies firma Sieb. et Zucc. A reduction in tracheid length occurred with the development of compression wood within a growth ring. Such a decrease in tracheid length was considered to have resulted from a conspicuous increase in the frequency of cell divisions. Formation of compression wood was also accompanied by an increase in certain morphological features of the tracheid tips, indicating that the intrusive growth of the tracheid tips did not proceed smoothly in compression wood. A negative correlation between the tracheid length and the occurrence of abnormal tracheid tips was established in a growth ring containing compression wood. Whereas the variance of tracheid length increased with increasing tracheid length in normal wood, no such relationship could be observed in compression wood.

Intra-increment circumferential variation in tracheid length as a basis for sampling genetically superior trees of deodar (Cedrus deodara (Roxb.) Loud.)

Intra-increment circumferential variation in tracheid length at breast-height in deodar (Cedrus deodara (Roxb.) Loud. vern. diar) has been studied with the main objective of evolving an efficient sampling procedure for the purpose of comparing tracheid length amongst individual trees of forest stands. It has been studied in five sampling strata namely: whole-annual ring, whole-earlywood, whole-latewood, first-firmed earlywood and last-formed latewood. Tracheid length shows significant circumferential variation in whole-annual ring, whole-earlywood, whole-latewood and last-formed latewood. However, when the mean tracheid length of two opposite directions is compared with the mean tracheid length of eight cardinal directions in these sampling strata, then no significant difference is observed. First-formed stratum of an annual ring exhibits statistically consistent values around the circumference and thus sampling from any random radial direction can serve the purpose for the comparison of inherent values of tracheid length amongst the deodar trees.

Effect of CO2 Enrichment on Wood Structure in Pinus Radiata D.Don

The wood structure of Pinus radiata trees grown under conditions of elevated atmospheric CO2 was investigated. Tracheid length, tangential and radial lumen diameter, and .tangen tial wall thickness were measured for trees grown at 320 ± 20 ppm CO2 and 640 ± ppm CO2.

Distribution of juvenile wood in two stems of Larixlaricina

The distribution and vertical variation of juvenile wood was studied in an 81-year-old dominant tree and an 83-year-old suppressed tree of Larixlaricina (Du Roi) K. Koch. Two criteria, growth ring width and tracheid length, were used to demarcate the boundary of juvenile wood. The width of juvenile wood, expressed in centimetres and the number of growth rings, decreased noticeably from the base to the top of the tree. The volume of juvenile wood decreased in a similar pattern. These decreasing trends had a strong negative correlation with the year of formation of cambial initials at a given tree level. The length of these cambial initials decreased with increasing age of formation of the cambial initials. In the juvenile wood zone, there was a positive linear regression between the growth ring number (age) and the tracheid length. The slopes of these regression lines at various tree levels increased as the age of the year of formation of the cambial initials increased. At a given tree level, the length of tracheids increased from the pith to a more uniform length near the bark. However, the number of years needed to attain a more uniform tracheid length decreased from the base to the top of the tree. These relationships suggest that the formation of juvenile wood is related to the year of formation of the cambial initials. Consequently, the juvenile wood is conical in shape, tapering towards the tree top.

Thigmomorphogenesis: anatomical, morphological and mechanical analysis of genetically different sibs of Pinus taeda in response to mechanical perturbation.

Twenty-three open pollinated families (half-sibs) and four controlled pollinated families (full-sibs) of Pinus taeda L. (loblolly pine) were grown in a greenhouse and analyzed for changes induced by mechanical perturbation (MP). These changes included inhibition of stem and needle elongation, bracing of branch nodes, and increased radial growth in the direction of the MP. Inhibition of stem elongation was the least variable feature measured. Leaf extension and stem diameter were highly variable between half-sibs. MP induced increased drag in greenhouse grown P. taeda in wind-tunnel tests. In P. taeda, MP induced decreased flexibility and increased elasticity and plasticity of the stem. The increased radial growth of the stems overrode the increase in elasticity, resulting in an overall decrease in flexibility. MP trees had a higher rupture point than non-MP controls. Increased radial growth is a result of more rapid cell divisions of the vascular cambium, resulting in increased numbers of tracheids. The decreased leader growth is partly due to a decreased tracheid length in response to MP.

Wood Anatomy of Pinus Longaeva (Bristlecone Pine) and the Sustained Length-on-Age Increase of its Tracheids

Length-on-age curves are presented for tracheids of three stems of bristlecone pine (Pinus longaeva). In the oldest stem tracheid length has steadily increased over the last 2200 years, and there are no signs of a levelling off. In the younger stems, which have the innermost rings dated 1484 and 1445 A.D., it appears that the 'juvenile' phase of steep increase in tracheid length of Pinus longaeva lasts several centuries. The methods of measuring tracheid length from narrow increment cores with a high percentage of damaged tracheids in macerations and in tangential sections using Ladell's method are compared. The wood anatomy of P. longaeva is described and found very similar to that of P. aristata. Both species differ in minor details from the related P. balfouriana. All three species share minute crystals in the epithelial and sheath cells of the resin ducts.

Drainage Effect on Growth and Wood Quality of Some Bog Grown Trees in Alberta

Growth rate, wood relative density and tracheid length variation were examined for three species: black spruce (Picea mariana (Mill.) B.S.P.), white spruce (Picea glauca (Moench) Voss), and tamarack (Larix laricina (Du Roi) K. Koch), from two drained wetland sites of north-central Alberta. Increased rates in radial and volume growths were noted for tamarack, white spruce and to a lesser extent, black spruce. The increases were particularly remarkable in younger trees. Accompanying the rapid growth, wood relative density and tracheid length tend to decrease after drainage, at least for a period of several years. In certain trees, the marked decreases in wood relative density might affect the end use of the trees. Key words: drainage, radial growth, volume growth, wood relative density, tracheid length.