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We showed that temperature responses of dark respiration for foliage of Pinus radiata could be approximated by Arrhenius kinetics, whereby E(0) determines shape of the exponential response and denotes overall activation energy of respiratory metabolism. Reproducible and predictable deviation from strict Arrhenius kinetics depended on foliage age, and differed between R(CO2) and R(O2). Inhibition of oxygen reduction (R(O2)) by cyanide (inhibiting COX) or SHAM (inhibiting AOX) resulted in reproducible changes of the temperature sensitivity for R(O2), but did not affect R(CO2). Enthalpic growth--preservation of electrons in anabolic products--could be approximated with knowledge of four variables: activation energies (E(0)) for both R(CO2) and R(O2), and basal rates of respiration at a low reference temperature (R(REF)). Rates of enthalpic growth by P. radiata needles were large in spring due to differences between R(REF) of oxidative decarboxylation and that of oxygen reduction, while overall activation energies for the two processes were similar. Later during needle development, enthalpic growth was dependent on differences between E(0) for R(CO2) as compared with R(O2), and increased E(0)(R(O2)) indicated greater contributions of cytochrome oxidase to accompany the switch from carbohydrate sink to source. Temperature-dependent increments in stored energy can be calculated as the difference between R(CO2)DeltaH(CO2) and R(O2)DeltaH(O2).

Leader dieback associated with B deficiency in P. radiata D. Don plantations was treated with borax applied at rates of 50, 100 and 150 kg ha -1. This initially increased B in foliage from 5 to 40, 80 and 110/xg g-~ respectively, and was followed by a rapid decline and stabilisation at around 25/xg g-I for the duration of the study. Annual fluctuations in foliage B levels were strongly correlated with rainfall during the preceding spring and summer. Uptake of N, P and K increased as a result of applied B and comparison of the distribution of these nutrients in crowns of fertilized and unfertilised trees six years after application indicated continued uptake of these nutrients probably as a result of improved root growth due to B. Foliage concentrations of B like N, P and K, increased in young needles towards the upper crown and this, together with a decline in needle concentrations of B as foliage aged, indicated some redistribution of B from older to new foliage. A limit of 5/zg g-1 was found below which little redistribution seems to occur.Application of B prevented further leader dieback, improved apical dominance and height growth and increased volume production by 25 m 3 ha-1 at age 8 years. Differences between application rates of B were not significant in terms of growth.

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Fifteen‐year old Monterey pine (Pinus radiata) was irrigated for 3 yr with wastewater derived from industrial and municipal sources. The wastewater contained high concentrations of Na2+ and HCO3− and was quite alkaline. Irrigation thus caused substantial increases in exchangeable Na2+, extractable P, exchangeable K+, pH, and the electrical conductivity of the soil solution. Highly colored organic compounds derived from pulp‐mill effluent apparently combined with inorganic N from municipal effluent to form organic N compounds. Nitrogen remained largely in the organic form and became concentrated in the groundwater with colored humic compounds. The greatest environmental hazard in the use of such blended wastewater for irrigation is the contamination of drainage water with colored, saline water containing high concentrations of organic N. The organic compounds appeared to inhibit nitrification in the groundwater.

Pinusradiata may exhibit moderate to severe stem deformity (Toorour syndrome) when planted on ex-pasture sites in southern Australia. However, the deformity does not occur on ex-eucalypt forest sites unless N fertilizer is applied. While the symptoms of Toorour syndrome are visually similar to those induced by Cu deficiency, the syndrome is associated with high foliar Cu concentrations (and concentrations of Mn and Zn). Furthermore, although Cu-deficient trees typically exhibit lower stem lignin concentrations than nondeformed trees, there is no apparent reduction in the stem lignin concentrations of trees exhibiting Toorour syndrome. Unlike Cu deficiency, the syndrome is not alleviated by Cu fertilizer applications. From comparisons of soil chemical properties between ex-pasture (deformed) and ex-eucalypt (nondeformed) sites, across a range of soil types and lithologies, it is concluded that (i) the syndrome is associated with previous land use rather than soil type or lithology, (ii) the syndrome is associated with the high fertility of ex-pasture soils, in particular, high NO3-N production, relative nitrification, and Mn availability, and (iii) it is unlikely that the syndrome is a consequence of single trace element or other element deficiencies.