Showing papers on "Pinus radiata published in 1977"

Above-ground dry matter, energy, and nutrient contents of trees in an age series of Pinus radiata plantations.

Abstract: Eight sample stands ranging in age from 2 to 22 years were studied to characterise dry matter, energy, and nutrient contents of the above-ground portion of intensively managed Pinus radiata D. Don plantations on a good site. Site index averaged 36 m at age 20. Dry matter content was closely comparable to similar data from Australia. Net dry matter production averaged 14.4 tonnes/ha/annum over the 22-year period; gross production was 22-25 tonnes/ ha/annum during initial canopy closure and during canopy closure after heavy thinning. Stand nutrient contents were predominantly in the order N = K>Ca>Mg = P>Mn>Na>Zn. The high potassium content probably reflects the potassium-rich pumice soils on which the stands were growing. Compared with published results for a wide variety of pine species, these stands had high rates of dry matter accumulation and nutrient uptake. Nutrient content in relation to dry matter content was high for potassium, low for calcium, and intermediate for magnesium and manganese compared with other pines. Heavy thinning-to-waste with high pruning of remaining trees would have returned about 55% of the nutrients in the above-ground stand to the forest floor. The total amounts returned would have been similar to those resulting from harvesting of the 22-year-old stand. The total energy capture and the percentage of incoming radiation stored in woody tissue were high compared with published data for other forest types, even though the silvicultural practices employed were not designed to maximise energy capture. INTRODUCTION Information on nutrient and energy content of plantations is of increasing importance as a basis for understanding the ecological impact and economic limits of continuous forest production. Recent suggestions that forests can supply a renewable source of energy (Szego et al., 1972; Troughton, 1976) heighten the need for data. Temporary sample plots covering an age series of stands have been used as a traditional method of studying the volume growth of forests. More recently, following the lead of Ovington (1957a), this method has been used to study dry matter production and nutrient uptake. Use of temporary sample plots in this way assumes that all sites studied are uniform throughout the age range. Such plots can give reasonable estimates of standing crop but N.Z. J. For . Sci. 7(3): 445-68 (1977). 446 New Zealand Journal of Forestry Science Vol. 7 estimates of periodic annual increment are not reliable (Spurr, 1952). Thus the data from such studies may be used to indicate general trends only. In New Zealand, Orman and Will (I960), Will (1964; 1966; 1968), and Gadgil (1976) have provided a number of estimates of dry matter production and nutrient content of Pinus radiata!). Don stands. In Australia, Forrest and Ovington (1970) have studied dry matter of P. radiata plantations up to age 12 years, with additional data provided in papers by Stephens and Bond (1957), Waring (1969; 1974), Siemon (1973), and Williams (1976). Data for one plantation are also available from Italy (Giulimondi and Duranti, 1975). The dry matter production and concurrent nutrient uptake of New Zealand P. radiata are of particular interest as the more productive sites carry some of the fastest-growing temperate conifer forests in the world. The purposes of the study reported here were to: (1) Determine the dry matter, energy, and nutrient content of an age series of P. radiata plantations on a high quality site; (2) Compare the results with comparable data from Australian plantations; (3) Place P. radiata dry matter production and nutrition in the perspective of pine as a genus. MATERIALS AND METHODS Sample Stands A series of eight plots, all within 9 km of each other, was selected in Pinus radiata plantations in the north-eastern corner of Kaingaroa Forest (38° 18'S, 176° 44'E). The average annual rainfall (1941-1970) for this area is between 1425 mm (Kopuriki, immediately south-east) and 1549 mm (Kaingaroa Forest Headquarters, to the southwest). The latter station has a mean annual temperature of 10.7 °C, with a seasonal range from 5.4°C in July u> 15.8°C in February, and an average of 107 ground frosts per annum. The sampled stands ranged in age from 2 to 22 years, and were growing on 75 to 100 cm of Tarawera scoria and Kaharoa ash, overlying older and more consolidated volcanic ash showers. These are classified as Matahina gravels or Matahina hill soils, with a site index of about 36 m at age 20 years (C. J. Goulding, unpubl.). Sample plots and stands chosen reflected as closely as possible the then current management practice of planting 2500 stems/ha, with live-crown pruning of selected crop trees to a height of 6 m followed by thinning to 540 stems/ha at about age 8 years, when the trees were 12 m tall. It was impossible to find stands over 10 years old which had received this treatment; thus, the 17-year-old plot had been thinned to 860 stems/ha, and the 22-year-old plot had been thinned at age 9 years. The 8-year-old stand had a low stocking (Beekhuis, 1966) and additional data on the effects of thinning and pruning, collected later, are included in the Appendix. Field Procedures In each plantation a previously established sample plot of 0.1 acres (approximately 0.04 ha) was selected and all the trees were measured for height and diameter. In the 8-year-old stand, which had been marked for thinning, a note was kept of trees to be removed. Sample trees covering the size range within each plot were felled. Seven trees were taken in unthinned plots and five trees in thinned plots. Sampling extended from June to September 1971. The crown of each sample tree was divided into zones No. 3 Madgwick et al.—Dry Matter, Energy and Nutrients in P. radiata 447 representing the year in which the branches were initiated. For each zone all firstand second-order branches were separated according to the age of needles which they bore, and each subdivision was weighed. Large subsamples were then separated into needles and woody material prior to being weighed after drying at 60 °C. Ratios of dry weight of needles and woody material to fresh weight were used to obtain estimates of total dry weight of each component for each zone of the crown. All cones within the crown were combined before drying and weighing. Male strobili were present on only the 2 2-year-old stand at the time of sampling. Stems were divided into sections and total fresh weight was determined prior to sampling for moisture content. Within the live crown each section comprised an annual height increment; below the lowest live branch, sections consisted of 2-metre lengths. Discs were cut from the end of each segment and at breast height for detailed study. Before drying, the discs were separated into* wood and bark. Laboratory Procedures In order to reduce the numbers of samples to be analysed, material was combined to provide one representative sample for each category of material for each tree. The categories chosen were needles by age class, live branches, dead branches, cones, strobili, stem bark, and stem wood. Canopy material was combined according to the relative proportion of material in each crown layer. Stem material was combined according to the relative weight of each segment of the stem. Woody material was chipped before grinding in a stainless-steel Wiley Mill, and needle material was ground directly. After drying, samples were ground to pass through a 1-mm round-holed sieve. Nitrogen was determined by a semi-micro-Kjeldahl procedure using a selenium catalyst (Bremner, I960). The ammonium N in the diluted digest was determined colorimetrically by an automated adaptation of the indophenol blue method. Phosphorus and cations (Na, K, Ca, Mg, Zn, and Mn) were determined after dry-ashing at 480 °C, Test solutions were prepared from a dilute hydrochloric acid extract of the ash after preliminary removal of silica by a process involving dehydration. Phosphorus was determined colorimetrically by an automated adaptation of the vanadomolybdophosphoric acid yellow method described by Jackson (1958). Cations were determined by atomic absorption spectrophotometry. For Ca and Mg, strontium chloride was added to the solutions as a releasing agent (at a concentration of 1500 ppm of Sr+) to prevent interference from aluminium and phosphate. All samples were analysed in duplicate. Analyses were repeated where the difference between duplicates relative to their mean values exceeded 6% for N , 4 % for P, 8% for K and Mg, 10% for Ca, and 14% for Zn. The variations m precision between elements reflect the known variation in analytical procedures (Madgwick, 1970b). Energy content was determined for ground samples using an adiabatic calorimeter (Lieth, 1965) and expressed on a dry weight basis. When the quantity of sample material was limited, the highest priority was given to nitrogen determinations and lowest to caloric value. Calculations The nutrient and energy contents of each sample tree were obtained by multiplying the oven-dry weight by the relevant concentration. Regressions were calculated relating 448 New Zealand Journal of Forestry Science Vol. 7 logarithm component dry weight and nutrient content to logarithm height for 2and 4-year-old stands and logarithm height X (diameter) for older stands. Total dry weight and energy content of stand components were found by applying these regressions to the unsampled trees after correction for bias due to logarithmic transformation (Finney, 1941). This method is known to give reasonably close estimates of dry weight and overestimates of error terms (Madgwick and Satoo, 1976). In the present study 9 5 % confidence intervals in unthinned stands were about ± 20% and in thinned stands ± 40% of estimated totals, respectively. Separate estimates were made for the 8-year-old stand (a) in its unthinned condition and (b) assuming that the stand had been thinned and crop trees pruned to a height of 6 m. Net annual

Soil temperature and drying cycle effects on water relations of Pinus radiata

Abstract: The influence of edaphic and atmospheric conditions on the development of plant water stress, water absorption by roots, and transpiration was studied with 2-year-old seedlings of Monterey pine (Pi...

Preliminary studies on a native Australian eucalypt forest invaded by exotic pines.

Abstract: In some parts of Australia, the exotic tree species Pinus radiata is invading native eucalypt forests from adjacent plantations. At one site, measurements have been made in order to determine the dispersal gradient and rate of population increase of the self-sown pines. From these, it is evident that, barring further human interference, a new type of mixed forest community will develop.

Dieback in high site quality pinus radiata stands — the role of sulphur and boron deficiencies

Abstract: Several forms of dieback of Pinus radiata D. Don within otherwise highly productive forests on the eastern highlands of New South Wales, Australia, are attributed here to physiological deficiencies of sulphur or boron, separately or in combination. Over this area there is a strong correlation between the incidence of dieback and soils (usually derived from extrusives or weathered granites) which are deficient in either or both of these elements. Marginal deficiency of either element could lead to the usual dieback symptoms; directly, by degeneration of the vascular system; indirectly, as in the case of sulphur by increased susceptibility and improved trophic conditions for pathogens such as Dipfodia pinsa. Both the level of deficiency, and the resulting symptoms, are subject to seasonal effects.

Comparison of bird counts from pine forest and indigenous vegetation

Abstract: Bird counts were taken in Feb., March and July 1975 in 4 native habitats, ranging from wet sclerophyll Eucalyptus forest to mallee (E. stricta)-heath on the Boyd Plateau, and two Pinus radiata habitats (20 yr and 40 yr) in the Jenolan State Forest, New South Wales, Australia. In each season the number of birds and the number of species was highest in the native forest habitats, lower in the pine habitats and least in the mallee-heath. The composition of native forest, pine forest, and mallee-heath bird communities shows considerable differences.

Influence of nitrogen and phosphorus stresses on the growth and form of radiata pine

Abstract: Cuttings of two radiata pine (Pinus radiata D. Don) clones were grown for 6 years in lysimeters. Four soil conditions were used to study the effects of nutrition on tree growth and form — (1) subsoil, kept low in N; (2) subsoil, kept low in P; (3) normal proportions of topsoil and subsoil; and (4) double topsoil volume. The latter increased nutrient supplies — particularly of N. The major effects of N or P stress on the trees were to restrict (1) stem diameter growth more than height growth and (2) branch growth more than stem growth. In contrast, trees with access to the additional nutrients (particularly N) in the double-topsoil lysimeters had larger diameters at breast height in relation to height, and larger branches producing considerably greater quantities of foliage each year; however, foliage retention time was decreased.

Response of Radiata Pine to Salt Stress. I. Water Relations, Osmotic Adjustment and Salt Uptake

Abstract: Transpiration, total needle water potential and osmotic water potential, and proline concentration in needle sap were determined in radiata pine (Pinus radiata D. Don) seedlings subjected to a step- wise decrease in osmotic potential of their liquid rooting medium by addition of CaCl2 or NaCl (absorbable), or PEG 4000 (non-absorbable). Resultant concentrations of N, P, K, Mg, Ca, Na, and Cl were determined in needle, stem, and root tissue as well as in expressed needle sap. Seedling damage resulting from salt treatment was not due to water stress. CaCl2 caused greater damage than iso-osmotic concentrations of NaCI, and the damage was associated with Cl excess and an induced P deficiency. Seedlings rapidly salinized with NaCl rapidly and continuously absorbed ions into their needle sap until death, whereas those more slowly salinized appeared able to keep absorption to a lower level and escape visible injury. Proline accumulated in needle sap under both water and salt stress. Proline accumulation under salt stress could not be explained in terms of water stress alone. Radiata pine seedlings appeared better adapted to avoid rather than tolerate high ion concentrations in their living tissues.

Differentiation in pinus radiata callus culture: the effect of nutrients

Abstract: Pinus radiata D. Don callus maintained for 2.5 years by subculturing was observed to differentiate, producing nodules containing xylem, cambium, and phloem. It has been shown that there is a pronounced optimum in the concentra­ tion of sucrose and major nutrients for this differentiation. Reduced levels of either sucrose or major nutrients alone were not sufficient to induce formation of this vascular tissue, although simple-pitted parenchyma cells with some secondary walls were produced.

Response of Radiata Pine to Salt Stress. II. Localization of Chloride

Abstract: Seedlings of Pinus radiata D. Don (radiata pine) were subjected to a stepwise decrease in the osmotic potential of their rooting medium by the addition of CaCl2, NaCl or polyethylene glycol 4000. The location of chloride within the root, stem and needle tissue was determined at the ultrastructural level using a silver precipitation technique. Three main sites of chloride deposition were detected. In the roots, large amounts of precipitated chloride were observed in the hyphae of the mycorrhizas as well as between the cell wall and the plasmalemma of the outer cortical cells, suggesting that chloride was in part prevented from entering the root at these sites. In the stem, chloride was precipitated in the ray cells and in the tracheids where it occurred both in the cell lumen and in the inner layer of the secondary wall (the S2). Since tracheids constitute the largest proportion of a pine tree, this site could constitute a considerable sink into which excess chloride could be deposited, thus removing it from cellular metabolism. In the needles, chloride was precipitated in the epidermal and sub-epidermal cells, and in the mesophyll it was mainly located in the cell walls. In all living cells in the seedlings, chloride was precipitated mainly in the vacuoles. It was restricted to small discrete deposits in the cytoplasm and was absent from the ground plasm and organelles. These observations support the hypothesis that, although radiata pine cannot tolerate high concentrations of chloride in vital tissues, it is adapted to avoid or delay its accumulation in such sites.

Reassociation of a modified mycorrhiza with the host plant roots ( Pinus radiata ) and the transfer of acetylene reduction activity

Abstract: Experiments were carried out to assess the potential for reassociation of modified strains of the mycorrhizal fungus Rhizopogon sp., capable of acetylene reduction activity in vitro, with the roots of its host plant (Pinus radiata). Reassociation was effected and acetylene reduction assays indicated that nitrogenase activity was present in the reassociated whole plants. Those host plants symbiotic with the modified strains had higher levels of nitrogen than those associated with the wild type fungus under nitrogen deprived conditions. Uptake of phosphate was unimpaired in the modified mycorrhiza. Electron microscopy showed that hyphae of the modified strains as well as lying in the intercellular spaces were often found within the cells of the root cortex. This was in contrast with the wild type strains where no such intracellular growth was found. One strain was sound to be pathogenic to seedlings of Pinus radiata. re]19760603

Bark Banding of Pinus radiata with Morphactin (IT3456): Influence on Trunk Anatomy Assimilate Transport and Growth

Abstract: A morphactin formulation containing methyl-2-chloro-9-hydroxyfluorene-9-carboxylate as the major component caused abnormal stem growth in Pinus radiata D. Don seedlings when applied as a bark band. The banded region swelled due to increased cell division in the periderm and cambium. The abnormal stem development in treated trees did not cause a localized girdling effect. The morphactin treatment inhibited shoot elongation and root growth. Treated trees exposed to 14CO2 translocated significantly less assimilate to the roots than did control trees although fixation of 14CO2 by the shoots was not reduced. Label from a bark band of 14C-morphactin was rapidly translocated to the roots indicating that direct inhibition of root growth by the inhibitor probably occurred.

Tests on a Field Method for the Determination of Wood Density

Abstract: A field method of determining wood density originally proposed by Polge and Keller (1970) was tested on plantation-grown Pinus radiata D. Don. The trials showed that the torque required to drive an...