Thesis (Ph. D.)--Oregon State University, 2009. / Printout. Includes bibliographical references. Also available on the World Wide Web.

Thesis (Ph.D. Biological Sciences)--University of Waikato, 2009. / Title from PDF cover (viewed July 10, 2009) Includes bibliographical references (p. 184-202)

Thesis (Ph. D.)--University of Canterbury, 2006. / Typescript (photocopy). Includes bibliographical references (leaves 109-118). Also available via the World Wide Web.

Thesis (MScFor)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: The aim of this project was to determine the site effect- especially water availability - and the effect of cambial age on selected anatomical properties of Pinus radiata, in order to be able to predict possible changes in wood quality due to an expected change in climate. A second objective was to correlate ring and fibre properties, in order to determine, if ring properties could be used as a proxy to describe wood quality. The samples consisted of 12 trees, sampled at an age of 1 to 16 from six selected sites in the Western Cape, which ranged from water stressed to moist. Apart from the water availability all other external factors, such as elevation etc. were kept as equal as possible. Anatomical wood properties such as fibre length and fibre diameter, lumen diameter, cell wall thickness, ring width and earlywood/latewood ratio were determined and their change with cambial age and water availability was evaluated. Fibre length, fibre diameter and cell wall thickness increased with increasing cambial age, and ring width and earlywood/latewood ratio decreased with increasing cambial age. No significant correlations were found between any of the ring or fibre properties and water availability. Most of the fibre properties were significantly correlated with ring width and earlywood/latewood ratio when age was not considered as covariate, but showed no correlation when the age effect was excluded. / AFRIKAANSE OPSOMMING: Die doel van die projek was om die perseel se effek te bepaal, veral water beskikbaarheid, ten opsigte van die effek van kambium ouderdom en geselekteerde anatomiese eienskappe van Pinus radiata, om sodoende die moontike verandering in hout kwaliteit as gevolg van verwagte klimaatsverandering te voorspel. ‘n Tweede doelwit was om die ring en vesel eienskappe te korreleer en ook te bepaal of ring eienskappe gebruik kan word om hout kwaliteit te beskryf. Die monsters het bestaan uit bome van ses geselekteerde persele in die Wes Kaap en het gevarieer van ‘n water tekort na klam. Behalwe vir water beskikbaarheid is al die ander eksterne faktore, soos hoogte ens., konstant gehou waar moontlik. Anatomiese hout eienskappe soos vesel lengte en deursnee, sel deursnee, selwand dikte, ring wydte en E/L verhouding was bepaal asook die verandering met kambium ouderdom en water beskikbaarheid. Vesel lengte , vesel deursnee en selwand dikte het toegeneem met toename in kambium ouderdom, en ring wydte en E/L verhouding het afgeneem met toename in kambium ouderdom. Toename in water beskikbaarheid het gelei to afname in vesel lengte en selwand dikte, waar vesel deursnee, sel deursnee, E/L verhouding en ring wydte toegeneem het. Meeste van die vesel eienskappe het betekenisvol gekorrelleer met ring wydte en E/L verhouding wanneer ouderdom nie as ko-variant gebruik is nie.

Thesis (MSc)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: This study aimed to classify wood from trees that were exposed to forest fires with regards to their end use. Exposure to high temperatures over time is known to degrade wood in various ways. This degradation could limit the end use by altering mechanical, chemical and physical properties, leading to difficulty in processing or failing to meet required specifications for various grades. In this study wood from Pinus radiata trees that were exposed to forest fires of different levels of heat intensity was analysed with regards to its anatomical and physical changes. Trees were visually classified into three classes of burn severity. Moisture content measurements were taken from 135 standing trees, divided among the three classes. 30 trees, 10 from each of the three classes, were sampled and used for CT analysis. Samples were taken to include growth from before and after the fire. Two samples were taken from each tree, one from the charred and one from the uncharred side. The CT data was analysed and used to measure properties like growth ring width, cell wall thickness, lumen diameter and cell wall density. The data was used to compare properties from the charred and uncharred sides within a given year, as well as compare properties between years. The study showed that there were significant differences in the MC between the burnt and unburnt sides of trees from classes 2 and 3. The difference between the MC measurements on the burnt sides of three classes differed significantly from each other. Lightness measurements were taken on samples from classes 2 and 3. These samples showed no significant difference between the burnt and unburnt sides for either of the two classes. The samples from the less exposed class were lighter, but not significantly so. The macroscopic wood density was determined using core samples. A decrease in wood density was observed with an increase in fire exposure. The mean densities for all three classes however still fulfilled the requirements for structural timber set by the SABS. Growth ring width, cell wall thickness and lumen diameter analysis gave varied results, with some cases showing a decline in properties while others were seemingly unaffected. For many of the outcomes of this study, results found by previous studies could not be reproduced. / AFRIKAANSE OPSOMMING: Hierdie studie het gepoog om bome wat aan plantasiebrande blootgestel is volgens hul eindgebruik te klassifiseer. Dit is bekend dat blootstelling aan hoë tempreature hout in vele maniere afbreuk. Hierdie afbreuking kan die eindgebruik van die hout beperk deur die meganiese, fisiese en chemiese eienskappe sodanig te verander dat dit kan lei tot probleme met verwerking of ongeskiktheid vir sterktegrade. In hierdie studie is Pinus radiata bome wat aan plantasiebrande van verskillende grade blootgestel is ondersoek in terme van hul fisiese en anatomiese veranderinge. Bome is visueel in drie klasse van verskillende brandskade gegroepeer. Voglesings is op 135 staande bome, verdeel tussen die drie klasse, geneem. Monsters is van 30 bome, 10 uit elke klas, geneem vir CT analiese. Monsters is so geneem dat dit groei van voor en na die brand ingesluit het. Daar is twee monsters van elke boom geneem, een van die gebrande en een van die ongebrande kant. Die CT data is geanalieseer en gebruik om eienskappe soos jaarringwydte, selwanddikte, lumendiameter en selwand digtheid te meet. Die data is gebruik om eienskappe tussen die gebrande en ongebrande kante, sowel as tussen jare te vergelyk. Die studie het gewys dat daar noemenswaardige verskille is tussen die voginhoud van die gebrande en ongebrande kante van bome uit klasse 2 en 3. Die voginhoud van die gebrande kante van al drie klasse verkil ook noemenswaardig van mekaar. Ligtheidmetings is gedoen op monsters van klasse 2 en 3. Die monsters het nie ‘n noemenswaardige verskil tussen die gebrande en ongebrande kante getoon nie. Alhoewel die klas 2 monsters ligter vertoon het as die klas 3 monsters, was die verskil nie betekenisvol nie. Houtdigtheid is bepaal deur fisiese metings op die monsters wat vir die CT skandering gebruik is te doen. ‘n Daling in digtheid met ‘n toename in blootstelling aan die brand het duidelik na vore gekom. Die digtheid is egter nog hoog genoeg om aan die vereistes vir strukturele hout te voldoen, soos die die SABS bepaal. Jaarringwydte, selwanddikte en lumen diameter het wisselende resultate opgelewer, met sommige gevalle wat ‘n afname in eienskappe wys en ander wat ooglopend onveranderd was. Vir vele van hierdie uitkoms kon die resultate van vorige studies nie bevestig word nie.

In South Africa, the limited extent of indigenous forests accelerated the development of fast-growing introduced species plantations, on which the country is now heavily reliant for its fibre and timber products. However, the plantation forestry industry is challenged with limited freshwater resources, the need for sustainable management of introduced tree species in commercial forest production systems, and a diversity of plant ecological production factors such as soils that have to be manipulated for the purposes of increasing production capacities. Additionally, plantations are established in the limited high rainfall regions of the country and the industry’s water use has been regulated since 1972. Conversely, natural forests also provide valuable goods, however, their slow growth rates have restricted their development as commercial tree production systems. In this regard the forestry industry is continuously seeking to provide for the country’s timber and fibre needs while ensuring the provision of other ecosystem services from tree production systems. Recent developments in the forestry industry have therefore been focused on water use efficiency in current and alternative tree production systems. There is also widespread unsubstantiated belief that indigenous tree species are efficient users of water. Against this background this study sought to explore the single tree water use and water use efficiencies of introduced commercial plantation species (Pinus radiata) and that of important indigenous species (Ilex mitis, Ocotea bullata and Podocarpus latifolius) for timber and fibre production in the southern Cape region of South Africa. Single tree water use measurements were carried out for a year using the heat pulse velocity method. Growth measurements for utilisable stem wood were done on a quarterly basis for the specimen trees and growth increments over the year were determined. Single tree water use efficiency was a calculated as a function of grams of stem wood gained per litre of water transpired. Measurements of daily weather conditions and soil water content were concurrently taken during the year. The relationships between the variables that express daily climatic conditions, soil water content and daily volumes of transpired water were explored. Empirical models for the prediction of daily transpiration as a function of climate and soil water content were then developed using multiple linear regression analysis. Pinus radiata trees exhibited higher totals of volumetric transpiration than the indigenous species. The water use patterns of Pinus radiata showed higher peaks of maximum and minimum daily and seasonal water use while the indigenous species showed temperate patterns of water use throughout the year. Podocarpus latifolius attained the lowest water use efficiency in the year (0.49g/L) while Pinus radiata, Ocotea bullata and Ilex mitis had comparable water use efficiency values ranging between 1g/L to 2.50g/L. Significant positive correlations existed between climatic variables and daily sapflow volumes of the tree specimens. Daily total solar radiation showed the highest positive correlation with daily transpiration and the average value of the correlation coefficient for solar radiation and water use for all tree species was 0.70 (p < 0.001). Empirical models for predicting daily water use integrated the variables expressing plant available moisture and energy. The study enhances our understanding of single tree water use, water use efficiency, the drivers of transpiration and the applicability of such studies in developing rapid estimation techniques for water use in current and alternative South African tree production systems.

Memoria para optar al Título Profesional de Ingeniero Forestal / La madera de pino radiata, principal recurso maderero del país, es de baja durabilidad. Hongos e insectos, entre otros factores de su deterioro, son usualmente los más relevantes. Del grupo de los insectos, en particular la termita subterránea “Reticulitermes flavipes”, representa hoy la mayor preocupación, por su agresividad y avance permanente en áreas pobladas del país. El arseniato de cobre cromado (CCA) fue, por décadas, el preservante más utilizado en todo el mundo para proteger la madera, sin embargo, preocupaciones medioambientales, hace más de diez años, dieron paso a un cambio hacia otros productos. El uso de cobreazoles (CA) y en particular el de tipo B, junto con cobreazol micronizado, han sido los cambios más importantes desde entonces a nivel mundial. Su incorporación al mercado local, sin embargo, ha sido muy lenta, básicamente por costo y por no existir un marco legal que regule el uso de madera tratada con CCA. Sobre la base de los requisitos exigidos por la Australian Standard®, AS 1604.1-2012, para madera tratada con CA-B, el objetivo del estudio fue evaluar el comportamiento de madera de Pino radiata tratada con CA-B, a retenciones menores a las exigidas por la Norma Chilena, frente al ataque de hongos de pudrición y termita subterránea. Los métodos empleados fueron; “Standard Test Method for Wood Preservatives by Laboratory Soil-Block Cultures”, descrito en la ASTM Designation: D1413 − 07ɛ1 y la Norma Chilena NCh 3060.Of 2007, para el estudio con hongos y termita subterránea respectivamente. En el estudio con Lentinus lipideus, todos los grupos de retención presentaron efecto positivo en el control del hongo y diferencias estadísticamente significativas respecto a las probetas testigo. En el caso de Coriolus versicolor, solo los grupos de retención 1,4 y 1,8 kg/m3 se diferenciaron estadísticamente del testigo en el control del hongo. En el estudio contra termita subterránea, la retención necesaria de CA-B para el control de Reticulermes flavipes se ubicó entre las retenciones 1,4 y 1,8 kg/m3 (concordante con la Norma NCh 819:2012). Una retención menor en pino radiata tratado con CA-B, no pudo ser validada para el control de termita subterránea, Reticulermes flavipes.

Monterey pine (Pinus radiata), a native tree to California and two Mexican islands, is important both ecologically and economically. Outside native stands, Monterey pines are grown for landscaping in California and on plantations around the world. Pitch canker, a disease caused by the fungus Gibberella circinata Nirenberg & O’Donnell (Fusarium circinatum Nirenberg and O'Donnell) is threatening the survival of Monterey pines. The disease currently affects Monterey pines in many parts of the world including the native stands. No effective chemical or biological control is available but some Monterey pines show resistance to the disease. The purpose of this project was to develop a working protocol for producing genetic clones of the resistant pines through micropropagation. These genetic clones will be used for outplanting in places outside the native stands for ornamental and plantation purposes. This project analyzes the results of ten trials with varied parameters and bases the final protocol on the parameters used in the trial that induces the growth of new shoots. The final protocol developed in this project describes, step-by-step, the media preparation for the initiation, plant material collection, surface sterilization of plant material, plating in media and initiation of shoots on explants. The protocol calls for collecting shoot tips with hardened buds that have not yet elongated, then washing the shoot tips in sterile water with Tween 20 for 15 minutes. The shoots tips are then surface sterilized in a 50% bleach solution for 20 minutes. The explants are broken into disks (to minimize damage to the cells) by inserting the tip of a scalpel and tilting it slightly. The initiation media shown to induce growth consists of ½ strength LePoivre basal salt mixture, 5mg/L benzylaminopurine, 3% sucrose and 0.8% agar and is adjusted to a pH of 5.7, then autoclaved for 20 minutes. The explants are inserted into solidified media and incubated in a growth chamber programmed for 16 hours of light and 8 hours of dark with temperatures of 27ºC and 22ºC and light irradiance of 80µEm-2s-1. After 1 month the protocol calls for transferring the growing shoots to elongation media with full LP basal salts and transferring every month. When the number of desired shoots has been reached the forthcoming protocol for rooting can be followed.

The future resilience of Pinus radiata D. Don (Monterey pine) is dependent upon the development of a silviculture program inclusive of either preventative or management techniques for the potentially fatal pitch canker disease (Fusarium circinatum Nirenberg and O’Donnell [=F.subglutinans (Wollenw. & Reinking) Nelson et al. f. sp. Pini). As an ecologically and commercially valued species, a myriad of factors threaten the genetic resources of the geographically limited natural range. This study evaluated the effectiveness of uneven-aged forest management for regeneration success in the native, pitch canker infected Año Nuevo stand at Swanton Pacific Ranch in Davenport, California. Seedling survival and growth averages were used to evaluate the impact of the variables of gap size (0.20-hectare, 0.10-hectare, and 0.05-hectare), site-preparation treatment (pile and burn, lop and scatter), and parent tree (13 local seed sources). Pitch canker symptoms were quantified to conclude if there is indeed a range of expressed resistance according to parent tree. Statistical models (i.e. ‘mixed effect’) yielded moderately significant differences in odds of survival between site treatments, with pile and burn plots producing higher survival rates (p=0.066). No significant difference in survival was detected between gap-sizes (p=0.936 and 0.803, 0.05- and 0.10-hectare gaps respectively to 0.20-hectare reference). Significant variation was expressed (estimate=0.1219, SE=0.057) between the 13 parent trees, implicating usefulness in predicting seedling survival. ‘Mixed effect’ models only detected a significant effect from gap-size on growth measures: 0.20-hectare gaps yielded height and diameter measures significantly larger than 0.05-hectare gaps (p=0.027 and 0.0081 respectively). Contingency tables detected significant association between gap-size and number of pitch canker branch symptoms. The range of infection rates produced by the 13 parent trees did not prove significant by analysis. Pile and burn site preparation treatment increases the probability of survival for artificially regenerated seedlings and 0.20-hectare gaps yield significantly higher growth averages over 0.05-hectare gaps.

The influence of initial stocking and physiologically aged cuttings (taken from 1-year- old and 5-year-old parents) on corewood modulus of elasticity (MOE) in 6-year-old Pinus radiata D. Don was studied in a Nelder-design experiment in Rolleston, Canterbury. In the same experiment, the influence of initial stocking on MOE in 5-year- old Eucalyptus nitens was also investigated. The study incorporated 19 different stocking levels ranging from 207 to 40,446 stems/ha. Green dynamic modulus of elasticity was assessed in standing trees using the TreeTap stress-wave method over the lower part of the stem (0.3 – 1.9m) for 151 P. radiata trees and 115 E. nitens trees. The interaction between species and stocking significantly influenced MOE (P<0.001). MOE of P. radiata increased by 55% (or 3.9 GPa) between 271 and 40,466 stems/ha, and by 41% (or 2.2 GPa) between 271 and 4370 stems/ha. MOE of E. nitens was also influenced by stocking but the slope was significantly lower indicating that the effect of stocking was less pronounced than for P. radiata. Over the usual range of stockings for E. nitens there was an insignificant relationship between stocking and stiffness (P=0.335). Trees were also assessed for DBH, height, and stem slenderness (height/ DBH). None of these latter variables had a significant influence on MOE after the effects of stocking and species were accounted for. No effects of physiological age of cuttings were detected in this study. The findings of this study highlight the importance of stocking as a tool that forest managers can utilize to regulate corewood stiffness in P. radiata trees. These results also suggest that for E. nitens, where wood stiffness is a priority, forest managers could reduce establishment costs by planting at much lower initial stockings. This study also highlights the superior stiffness of E. nitens in direct comparison with P. radiata, with many trees in the experiment already exceeding stiffness thresholds for structural timber in New Zealand.