NZJFS - Volume 13 (1983)
Corrigendum for Webber, B., & Madgwick, H.A.I. 1983: Biomass and nutrient content of a 29-year-old Pinus radiata stand. 13 (3), 370.Webber, B., & Madgwick, H. A. I.
The paper which this Corrigendum refers to is available here: Biomass and nutrient content of a 29-year-old Pinus radiata stand
Letter to the editor: Statistics.Barton, I. L.
Book review - Hunt, D.M., Clarke, R.T.J., Bell, D.J., Earle, R.L., Joblin, K.N., & Scott, D.B. (Compliers),1983: Biotechnology in New Zealand.Smith, D. R.
Book review - Bootle, K.R. 1983: Wood in Australia.Harris, J. M.
Book review - Bonga, J.M., & Durzan, D.J. 1982: Tissue culture in forestry.Aitken-Christie, J.
Performance of unmodified and copper-modified alkylammonium-treated stakes in ground contact.Drysdale, J. A.
Pinus radiata D. Don sapwood stakes treated with two unmodified and two copper-modified alkylammonium compounds were examined during 4 years' exposure in the Whakarewarewa "graveyard". The stakes treated with benzalkonium chloride (10.6 kg/m3) and dialkyldimethyl ammonium chloride (6.2kg/m3) have been colonised and attacked by brown-rot, soft-rot, and white-rot fungi. Stakes treated with these chemicals modified by the addition of a cupric salt were in better condition. The modified treatments partially controlled white rot but treated stakes remained susceptible to soft rot and an unsightly brown erosion. This erosion is thought to be caused by brown-rot fungi. Although none of the four treatments examined is suitable for approval as a groundline treatment, copper modification still offers potential for this end-use and further formulation studies are considered worthwhile.
Estimating bark thickness of Pinus radiata.Gordon, A.
Bark thickness in Pinus radiata D. Don is related to over-bark diameter, position up the stem, tree height, and breast-height over-bark diameter. Equations have been derived for predicting bark thickness as a function of these variables and as a function of over-bark diameter alone. By using the bark thickness equations, routine bark-gauge measurements together with their associated measurement errors can be eliminated, which should accelerate the derivation of new, more precise, stem volume functions. The bark thickness equations, used in conjunction with a tree or log taper function, can provide estimates of the volume of bark to be harvested or available for utilisation.
Stand reorganisation to facilitate load accumulation in production thinning.Terlesk, C. J., McConchie, M., & Twaddle, A.
In harvesting operations such as production thinning where the piece size is small, the time involved in accumulating scattered felled stems into a sufficiently large load to match the capacity of the extraction machine can limit system productivity. Trials in which the stand was organised with a view to aiding harvesting were established in the early 1970s in Pinus radiata D. Don stands on a range of sites and terrain at Rotoehu, Turangi, and Woodhill Forests. Stockings were over the range 400-850 stems/ha, and the thinnings rows and final-crop rows were nominated early in the trial establishment.
The results of these trials showed that, with a 200 stems/ha final-crop prescription, small gains in productivity were achievable on flat country using a conventional skidder system, and larger ones on steeper country using a small skyline hauler. The increase in productivity obtained using a prebunching machine on flat terrain was not closely related to the reorganisation of the crop.
Longevity of response in Pinus radiata foliar concentrations to nitrogen, phosphorus, and boron fertilisers.Knight, P. J., Jacks, H., & Fitzgerald, R. E.
In the winter of 1972, a fertiliser trial was established in recently thinned (740 stems/ha) 4- to 5-year-old Pinus radiata D.Don regeneration in Harakeke Forest, Waimea County. In a factorial design experiment, nitrogen, phosphorus, and boron were variously applied as urea (168 kg N/ha), superphosphate (112 kg P/ha), and “fertiliser borate 65” (22 kg B/ha). Foliage samples were collected at monthly intervals for the first 3 years, and then about quarterly for 2 more years. Soil samples (0-10 cm) were collected at quarterly intervals and analysed for total nitrogen, Bray-2 phosphorus, Olsen phosphorus, and hot-water-soluble boron.
The concentration of all three nutrients in foliage increased steeply within a few weeks of application, reached a peak in the spring, and declined during the summer. Phosphorus levels then stabilised and remained consistently higher than in the controls for at least 5 years. Nitrogen and boron continued to decline, though at different rates; for nitrogen, the response lasted about 11 months, and for boron about 5 years. Increased levels of extractable phosphorus and boron persisted in the soil for the duration of the trial but appeared to be declining. The applied nitrogen had no obvious effect on soil total-nitrogen status. Tree growth data suggest (1) a positive effect of phosphorus on basal area increment lasting the full 5 years, (2) an effect of nitrogen on diameter increment lasting 1 year, and (3) no effect of boron.
Nutrient losses from litterbags containing Pinus radiata litter: Influences of thinning, clearfelling, and urea fertiliser.Will, G. M., Hodgkiss, P. D., & Madgwick, H. A. I.
A 4-year study using nylon mesh bags in a Pinus radiata D. Don stand showed that tree canopy density had little or no effect on litter decomposition rate or loss of nutrients. The application of urea at 200 kg N/ha raised the nitrogen concentration in the litter by 0.5%; even though this higher margin was consistently maintained throughout the study, decomposition rate and nutrient release were unaffected.
During the study relative rates of loss of dry weight and nutrients from litterbags were nitrogen <
Morphology of long-shoot development in Pinus radiata.Bollman, M. P.
Long-shoot initiation in buds of Pinus radiata D. Don is first indicated when the growth rate of axillary primordia nearest the apex appears to exceed that of those located lower in the bud. A basipetally increasing number of primordia is affected by this accelerated growth. Primordia which will become branches form their own axillary primordia. Those which are to develop into seed cones increase the size of the apical dome as a result of a temporary halt of primordium scale initiation and, possibly, of continuing meristematic activity in the pith tissue immediately below the rib meristem. Long-shoot primordia which will remain vegetative grow at a faster rate than those which differentiate into seed cones. In any one bud, therefore, branch primordia are much larger and heavier than seed-cone primordia.
Researchers wishing to influence differentiation of long-shoot primordia in the bud will need to be selective in the choice of bud material and in the timing of possible treatments. Examination of the annual growth patterns of the shoot below the bud should enable them to do so more accurately.
Control of feral goats by poisoning with Compound 1080 on natural vegetation baits and by shooting.Parkes, J. P.
The effectiveness of poisoning feral goats (Capra hircus L.) with Compound 1080 on natural vegetation baits was tested and compared with a hunting campaign. Both control methods probably killed over 90% of the goats in treatment blocks of 1200 ha, but the poisoning method required less skill than hunting. Melicytus ramiflorus Forst., Schefflera digitata J.R. et G. Forst., Coprosma lucida J.R. et G. Forst, and C. australis (A. Rich.) Robinson proved to be useful bait species in terms of their palatability and durability. The Compound 1080 gel used in the trial was too acid, causing chlorosis and eventual abscission of treated leaves.
Distribution and abundance of browsing mammals in Westland National Park in 1978, and some observations on their impact on the vegetation.Pekelharing, C. J., & Reynolds, R. N.
The high country forests and scrublands of Westland National Park were surveyed by means of pellet lines during the 1977-78 summer to determine the distribution and abundance of the larger introduced mammals. The extent of canopy defoliation in the upper montane forest zone of the Park was also assessed.
Brush-tailed possums (Trichosurus vulpecula Kerr) were present throughout the Park with the exception of the headwaters of the Karangarua, Douglas, and Regina catchments. Highest pellet densities were recorded in the mid and upper montane forests and in the northern and southern portions of the Park (in the lower reaches of the Callery and Karangarua catchments). Possums were still in the process of colonising the lower southern bank of the Copland catchment and the upper half and lower northern bank of the Karangarua catchment. Red deer (Cervus elaphus L.) pellet densities were highest in the forested zone of the lower Karangarua catchment and decreasd towards its headwaters and northwards. Numbers in the Cook catchment were low and no deer pellets were recorded in the study area north of this catchment. Chamois (Rupicapra rupicapra L.) pellets were recorded throughout the Park with highest densities around timber line in the upper forest and scrub zones. Highest pellet densities were recorded in the headwaters and lower northern bank of the Karangarua catchment and in the Callery catchment. Relatively low densities were measured in the forests between the Cook and Callery catchments. Goat (Capra hircus L.) pellets were recorded only north of the Karangarua River in the vicinity of Havelock Creek, where highest numbers occurred in the lower forest zone.
Over half the montane forests showed some canopy defoliation, the degree of which appeared to be related to the length of occupation by possums and their density. The lower reaches of the Karangarua, Copland, and Callery catchments showed the most striking canopy defoliation and contained the highest possum densities. The collective browsing pressure from high densities of possums, chamois, and deer was affecting all stages of forest structure and composition in the lower Karangarua catchment.
Letter to the editor: Corrigendum for Gifford, H.H. et al. 1982: Design of a new weighing lysimeter for measuring water use by individual trees. 12(3), 448-456.Whitehead, D.
The paper which this Corrigendum refers to is available here: Design of a new weighing lysimeter for measuring water use by individual trees
Book review - Douglas, J.J. 1983: A re-appraisal of forestry development in developing countries.Horgan, G. P.
Three-year response of Pinus radiata to several types and rates of phosphorus fertiliser on soils of contrasting phosphorus retention.Hunter, I. R., & Graham, J. D.
Superphosphate and three types of rock phosphate were applied to phosphorus-deficient young Pinus radiata D. Don crops growing on soils of contrasting phosphorus retention. On the soil of medium (50%) retention there were strong responses to the fertiliser after 3 years and the response was in proportion to the citric acid solubility of the material (i.e., superphosphate gave the greatest response - an unreactive aluminium phosphate the least). At the site of high phosphorus retention (92%) no statistically significant differences have yet emerged either between types of fertiliser or between plots with and without fertiliser. At the zero phosphorus-retention site, plots with fertiliser have grown slightly more than those without but no difference between fertiliser types has emerged.
Biomass and nutrient content of a 29-year-old Pinus radiata standWebber, B., & Madgwick, H. A. I.
A 29-year-old Pinus radiata D. Don stand contained 426 tonnes of aboveground standing biomass per hectare. This included 434 kg N/ha, 66 kg P/ha, 464 kg K/ha, 333 kg Ca/ha, 102 kg Mg/ha, 4.7 kg Zn/ha, 8.6 kg Fe/ha, 28.9 kg Mn/ha, 35 kg Al/ha, and 54 kg S/ha.
A Corrigendum to this paper is available here: Corrigendum for Webber, B., & Madgwick, H.A.I. 1983: Biomass and nutrient content of a 29-year-old Pinus radiata stand
Dry matter, nitrogen, and phosphorus content of litterfall and branchfall in Pinus radiata and Eucalyptus forests.Baker, T. G.
The mass, nitrogen content, and phosphorus content of litterfall was estimated in five Pinus radiata D. Don and four Eucalyptus forests in Gippsland, Victoria. Litterfall in pines ranged from 258 to 386 g/m2/year, and in eucalypts from 388 to 686 g/m2/year. Dead foliage was the major component of litterfall in both forest types. Litterfall in eucalypts peaked in summer; in pines it peaked both in spring and in late summer to early autumn.
Concentrations of nitrogen and phosphorus in dead foliage varied markedly between seasons but were consistently lowest at times of peak fall of dead foliage. The nutrient content of litterfall in pines ranged from 1400 to 2400 mg N/m2/year, and 97 to 230 mg P/m2/year. In eucalypts, the corresponding ranges were 2100 to 4600 mg N/m2/year and 94 to 200 mg P/m2/year. In comparison with litterfall, branchfall returned only small amounts of nitrogen and phosphorus to the forest floor.
Concentrations of nitrogen in litterfall of pine and eucalypt forests were comparable; however, concentrations of phosphorus in pine litterfall were usually greater than those in eucalypt litterfall.
Nitrogen concentration in foliage of Pinus radiata as affected by nitrogen nutrition, thinning, needle age, and position in crown.Madgwick, H. A. I., Beets, P. N., Sandberg, A. M., & Jackson, D. S.
Foliar nitrogen concentrations were sampled at four positions on three Pinus radiata D. Don trees in each treatment of a 7-year-old replicated thinning x nutrition experiment. Nitrogen concentration decreased with needle age and from top to bottom of the crown, but was unaffected by thinning treatment. In 1-year-old foliage the decrease in foliar nitrogen from top to lower middle of the crown was similar over the range of nitrogen states examined. As needles aged, differences in needle nitrogen among nutritional treatments decreased.
Soil water in deep Pinaki sands: Some interactions with thinned and fertilised Pinus radiata.Jackson, D. S., Jackson, E. A., & Gifford, H. H.
In an experimental comparison of Pinus radiata D. Don planted with or without yellow tree lupin (Lupinus arboreus Sims), versus with or without fertiliser, the lupin and fertiliser combination had 60-70% greater volume production than the controls by tree age 13 years. Depletion of soil water by the more productive stands was also much greater, and could cause critically low levels of soil water potential (-5 bars or less) throughout the profile during late summer and autumn. Critical depletion did not occur in the less productive controls (no lupin or fertiliser).
During the first 7 years (up to the time of canopy closure) differences in stocking produced the most significant differences in soil moisture, but only in the top metre of sand. Thinning greatly reduced depletion of soil water, particularly by stands with fertiliser, but these effects rapidly diminished after 2 or 3 years, and became insignificant after 5 years. After canopy closure the effects of fertiliser began to override those due to stocking, and to produce significant soil moisture differences much deeper down the profile, at 3 to 4 m. Differences in soil water storage beneath extremes of treatment amount to c. 134 mm of rainfall at midwinter.
Lupin, fertiliser, and thinning effects on early productivity of Pinus radiata growing on deep Pinaki sands.Jackson, D. S., Gifford, H. H., & Graham, J. D.
A balanced application of nitrogen, phosphorus, potassium, calcium, magnesium, and sulphur fertilisers significantly increased height growth of Pinus radiata D. Don on Pinaki sands at Woodhill State Forest, but the presence of Lupinus a r bo reus Sims (yellow tree lupin) did not. Lupin died out of all stands ranging from 741 to 2224 stems/ha by tree age 5 years, but the benefits for basal area and volume increment continued to accumulate up to tree age 11. Stands that have had both lupin and fertiliser can produce 35-40 m3 annum on 2224 stems/ha, or double the increment of untreated stands at any stocking.
The maximum benefits from thinning were obtained only on fertiliser-treated stands, which were three or four times more responsive than untreated controls, particularly at stockings exceeding 1500 stems/ha. It is possible to increase the volume of the dominant trees by 40-50% by pre-competitive thinning in conjunction with fertiliser application, but there is a commensurate sacrifice of total production.
Comparison of compatible polynomial taper equations.Gordon, A.
Polynomial taper equations in the first, second, third, fourth, and fifth powers were fitted to two data sets, conditioned to be compatible to an existing total volume equation. Accuracy and precision were compared with other models that included one higher power term, the value of the exponent for which ranged from 8 to 40. The latter models showed an improvement in prediction of merchantable and butt log volumes as well as inside bark diameter, although still with slight bias in diameter prediction that varied with relative height.
Correlation of resistance to a pulsed current with several wood properties in living eucalypts.Wilkes, J., & Heather, W. A.
Pulse resistance, basic density, moisture level, heartwood extractives content, pH, and levels of sodium, potassium, calcium, magnesium, and manganese were determined for the inner and outer heartwood and the sapwood from 10 trees of each of six eucalypt species. In most instances pulse resistance was positively and significantly (p = 0.05) correlated with basic density (r2 = 0.3-0.8), but was weakly and/or inconsistently associated with the remaining factors. The usefulness of a pulsed current resistance meter in detecting decay in the eucalypts studied is possibly limited because a substantial change in only one or two of the relevant wood properties during decay may not induce a perceptible change in pulse resistance.
Drying properties of New Zealand-grown Acacia melanoxylon.Haslett, A. N.
The performance of Acacia melanoxylon R. Br. (Australian blackwood) boards 25 mm and 50 mm thick was assessed in terms of drying time, shrinkage, collapse, and degrade from warping and cheeking after either air drying, dehumidification drying, conventional kiln drying, or high temperature kiln drying. Even kiln drying at a dry bulb temperature of 70°C, wet bulb 60°C, did not cause undue surface checking. The major problem encountered was the extreme variability of drying rate; quarter-sawn heartwood took twice as long to dry as flat-sawn heartwood. Accelerated drying methods increased this difference and for this reason it is recommended that all material, particularly 50 mm and thicker, be air dried to about 30% moisture content before kiln drying. Air drying of 25-mm boards can be achieved in 12-20 weeks in Rotorua with final kiln drying taking 4-5 days.
Blackwood is a medium density hardwood which has a low shrinkage with only a slight tendency to collapse when dried at elevated temperatures. Preliminary air drying will minimise collapse, making final reconditioning unnecessary. Spring and twist were a problem in the material studied but this could largely be attributed to poor tree form. Warp should be low to minimal in material from silviculturally tended trees.
Longitudinal splitting of bark: a likely cause of "Type 3" resin pockets in Pinus radiata.Donaldson, L. A.
Cambial damage as a result of longitudinal splitting of the bark of 6-year-old Pinus radiata D. Don results in the formation of minor lesions (Type 3 resin pockets) in the subsequently formed wood. The distribution of this type of lesion in 11-year-old trees of P. radiata indicates a reduction in the frequency of such defects as bark development proceeds. The origin of resin exudation on the surface of the stem is sometimes related to the presence of these defects, but usually occurs as a result of rupture of resin sacs in the bark.
Differences in growth and weight of genotypes of pine with special reference to clones of Pinus radiata.Madgwick, H. A. I.
The correlations between tree height, diameter at breast height (1.4 m), number of branch clusters, number of branches, and branch basal area for nine New Zealand clones of Pinus radiata D. Don. were all positive, and similar to those found for six clones in Australia. While clones could, therefore, be graded according to size, principal component analysis indicated that there was a range of "branchiness" within a given size. Current branch basal area increment per unit stem basal area increment was broadly similar for all nine New Zealand clones. Distinct, differences among clones in the relationship of total branch basal area to stem basal area indicated that past growth rates of these two parameters must have been different, while slight differences among clones, if maintained, would lead to different relative rankings in the future.
Principal component analysis of component weights of genotypes of P. radiata, P. elliottii Engelm., P. taeda L., and P. virginiana Mill, suggested that genotypes could be rated in terms of both over-all size and relative branchiness. For these four species there was little indication that increasing the fraction of wood plus bark growth allocated to stems increased total stem production. However, this conclusion could reflect the relatively open-grown condition of the trees.
Corrigendum for Cremer, K. W., Borough, C. J., McKinnell, F. H., & Carter, P. R. (1982): Effects of stocking and thinning on wind damage in plantations. 12(2), 244-268.Cremer, K. W., Borough, C. J., McKinnell, F. H., & Carter, P. R.
The paper which this Corrigendum refers to is available here: Effects of stocking and thinning on wind damage in plantations
Book review - Atkinson, I. A. E. 1981: Vegetation map of Tongariro National Park, North Island, New Zealand.McKenzie, R. M. J.
Book review - Satoo, T. 1982: Forest biomass.Beets, P. N.
Estimation of the oven-dry weight of stems, needles, and branches of individual Pinus radiata trees.Madgwick, H. A. I.
Above-ground weight of forest plots - comparison of seven methods of estimation.Madgwick, H. A. I.
The basal area ratio method, unweighted regression of weight on tree diameter squared, and methods based on logarithmic regressions with a variety of published correction factors were compared using simulated sampling of nine forest plots. The bias and variability of estimates derived using the basal area ratio method, unweighted regression, and logarithmic regression without correcting for expected bias were less than when logarithmic regression was used with correction factors. Logarithmic regression appeared most affected by the inclusion of unrepresentative sample trees. The basal area ratio method yielded the most estimates closest to the measured plot weights and has the added advantage of being the simplest to apply.
Wood density as an indicator of the bending properties of Pinus radiata poles.Cown, D. J., & Hutchison, J. D.
The outer wood density of 57 Pinus radiata D. Don poles from two stands (aged 15 and 25 years) in the central North Island was assessed gravimetrically using increment cores and indirectly using a Pilodyn Wood Tester, and the poles were tested to destruction by cantilever loading. Relationships between wood density of the outer 20% of the radius and the poles' strength and stiffness in bending were found to be highly statistically significant. From these relationships and regional data for wood density, the bending properties of poles have been predicted for a range of crop ages and growing sites, and these predictions compared to the values given in the Timber Design Code. In this study, pre-preservation steaming of P. radiata poles appeared to influence their bending properties more than anticipated.
The Pilodyn Wood Tester was shown to be potentially useful for segregating poles into strength classes.
Electrical impedance and its relationship to frost hardiness in Pinus radiata.Greer, D. H.
The seasonal trend of stem electrical impedance in Pinus radiata D. Don seedlings over an 18-month period was found to be similar to that in published data for other conifers. Comparison with the seasonal pattern of frost hardiness averaged over three different years at the same site implied that impedance may be related to frost hardiness. However, there was a distinct hysteresis in the relationship between impedance and the hardening and dehardening phases of the seasonal hardiness pattern.
In seedlings induced to harden in controlled environments, a close relationship between impedance and frost hardiness was demonstrated but only for the period when the seedlings were actively hardening. From this relationship, impedance values of outdoor-grown seedlings were shown to correspond to their frost hardiness during the hardening phase (April to June in the Southern Hemisphere).
Electrical impedance ratio technique for rapid assessment of frost damage in Pinus radiata.Greer, D. H.
A simple, low-frequency, impedance technique has been applied to frost damage evaluation in seedlings of Pinus radiata D. Don. Stem resistive impedance at 100 Hz was measured before and after a frost to calculate a pre- to post-frost impedance ratio (ZR). By demonstrating a relationship between ZR and the proportion of seedlings surviving a frost (with no more than 30% needle damage) a relationship between ZR and expected survival was derived.
This relationship was used to predict the number of seedlings lightly or seriously damaged in each of two separate populations of seedlings subjected to a range of frosts. Frost damage, with up to one seedling in error out of each batch of six in one population and nine in the other, was correctly assessed in 78% and 90%, respectively, of the frosts of those populations. In frosts where more than 10% of the seedlings were incorrectly classified the impedance ratio tended to overpredict survival. Seedlings with a ZR <0.9 had a 100% chance of surviving, and this screening method could provide for rapid selection of material where no seedling loss is acceptable.
Regeneration patterns in Beilschmiedia tawa-dominant forest at Rotoehu.Smale, M. C., & Kimberley, M. O.
Regeneration in gaps and under closed high canopy, representing the gap and mature phases of the forest growth cycle, was investigated in two small areas within forest dominated by Beilschmiedia tawa (A. Cunn.) Kirk (tawa) at Rotoehu in the North Island of New Zealand. Significant differences in regeneration occurred between phases, and within phases diameter distributions varied among species. These results suggest differing replacement strategies among species, largely reflecting differences in shade-tolerance. Of the four major regenerating species, shade-tolerant tawa and Dysoxylum spectabile (Forst, f.) Hook. f. (kohekohe) commonly develop to advanced stages beneath closed canopies; relatively intolerant Litsea calicaris (A. Cunn.) Kirk (mangeao) and Knightia excelsa R. Br. (rewarewa) seldom do, apparently requiring gap formation for development to maturity. In the area where tawa and kohekohe were co-dominant in the canopy, they tended to replace each other, thus maintaining their co-dominance.
In forests where the gap phase is important, replacement trends may best be gauged from gap regeneration alone. Of the indices of species' relative importance tested, four juveniles of largest diameter appeared the most appropriate predictor of future canopy occupation in gaps.
Inoculation of Pinus caribaea var. hondurensis seedlings with Ganoderma lucidum in Fiji.Hood, I. A., & Bell, T. I. W.
Woodblock cultures of two isolates of Ganoderma lucidum sensu lato from a basidiocarp on a dead tree of Pinus caribaea var. hondurensis Barr. & Golf. (Caribbean pine) were used to inoculate 98 potted Caribbean pine seedlings in Fiji. Although the inoculum remained active for 22 months in direct contact with seedling roots, pathogenicity was not demonstrated using these isolates.
Resistance of Douglas-fir to Pseudocoremia suavis.Kay, M.
The resistance of a 70-year-old Pseudotsuga menziesii (Mirb.) Franco (Douglas fir) to a major geometrid defoliator has been investigated. The resistance was largely confined to the current-year foliage and Pseudocoremia suavis (Butler) (Lepidoptera : Geometridae) larvae feeding on this exhibited high mortality and reduced growth rates and final weights.
Reciprocal cross effects in Pinus radiata.Wilcox, M. D.
Twenty-nine pairs of reciprocal crosses of Pinus radiata D. Don were made by controlled pollination, incidental to producing full-sib families for progeny testing and third-generation selection.
Seed size of each cross was measured by the weight of 100 seeds. Of the two crosses of each full-sib family, the one with heavier seeds was classified as the "big-seeded" cross and that with the lighter seeds, the "small-seeded" cross. Seeds of the 58 crosses were sown in a replicated split-plot design in the nursery in October 1979. Heights of seedlings were measured in the nursery in March 1980, and in a field test in May 1981 and again in July 1982.
Significant reciprocal cross effects were detected in the nursery and field tests, with a general tendency for the "small-seeded" cross to be shorter than the "big-seeded" cross. Consequently, it was shown that selection among families at age 2 years after planting (mean height 228 cm) would result in one wrong selection (or culling) for every four correct ones.
Seasonal changes in the biomass of a young Pinus radiata stand.Madgwick, H. A. I.
The dry matter content of above-ground components of a clonal plantation of Pinus radiata D. Don was estimated at eight intervals throughout its fifth growing season after planting. Total above-ground dry matter increment over the 11-month period was 20 t/ha. Stem increment varied from less than 1 t/ha/ month in winter to 3 t/ha/month in summer. Branch growth was approximately 3 t/ha/annum and occurred mostly in spring and summer. Production of 5 t new foliage/ha followed a sigmoid growth curve similar to other pine species and was predominantly restricted to a 4-month period late spring and early summer.
Nitrate losses from disturbed ecosystems in New Zealand - a comparative analysis.Dyck, W. J., Gosz, J. R., & Hodgkiss, P. D.
Tube lysimeters were used to determine the relative potential of several ecosystems to lose nutrients through leaching after disturbance. The ecosystems examined were all on yellow-brown pumice soils and were dominated by species exotic to New Zealand: (1) Pinus radiata D. Don (radiata pine), (2) Pseudotsuga menziesii (Mirb.) Franco (Douglas fir), (3)Eucalyptus saligna Sm., and (4) Ulex europaeus L. (gorse). The treatments applied to the systems were trenching and weeding (for 1, 2, and 3), clearfelling (1), clearfelling followed by herbicide application and burning (2), and crushing and burning (4). Soil water was periodically collected from 10 lysimeters in each treated area as well as in undisturbed controls for up to 2 years after disturbance, and analysed for nitrate nitrogen as an indicator of nutrient loss. For the undisturbed systems nitrate loss was in the order gorse > > Douglas fir >
Growth and nutrition of Pinus radiata on a recent coastal sand as affected by nitrogen fertiliser.Hunter, I. R., & Hoy, G. F.
Two nitrogen fertiliser trials were established in nitrogen-deficient Pinus radiata D. Don growing on a recent coastal sand. Results after 5 years showed that nitrogen fertiliser induced a large increase in basal area growth, an increase in height growth, but no change in tree form. Foliar nitrogen concentrations were ephemerally increased by nitrogen fertiliser.