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The cost of harvesting short-rotation plantation eucalypts can be in excess of AU$2500 x [ha.sup.-1]. Despite this high cost, the extent to which harvesting productivity is affected by tree genetics is not well understood. We address this issue in a study of two 10-year-old genetic field trials of Eucalyptus globulus Labill. in Australia. Standing-tree traits analysed were survival, diameter at breast height, basal area, and stem straightness and forking. Harvest traits analysed were volume, time, and productivity. Genetic group and within-group genetic variation (additive and dominance), stand-level family variation, phenotypic and genetic correlations, and the effects of inbreeding were estimated for these traits. The different scenarios studied showed that plantation harvest productivity was affected by tree genetics to some degree but was mainly affected through positive covariation with stem diameter. Harvest productivity is thus unlikely to have been adversely affected by past selection. Although no significant additive or dominance genetic variation in stem forking or straightness was detected, weak phenotypic correlations were consistent with harvest productivity being higher in straighter trees with no forking. High inbreeding depression was evident for growth and survival; however, in open-pollinated progeny, this resulted in only a slight reduction in harvest productivity (5.5%) compared with out-crossed progeny. Key words: harvest productivity, additive genetic variation, dominance genetic variation, inbreeding depression, standing-tree traits. Le cout de la recolte de bois d'Eucalyptus en plantations a courte revolution peut atteindre plus de 2500 $A x [ha.sup.-1]. En depit de ce cout eleve, l'influence de la genetique de l'arbre sur la productivite de la recolte est peu comprise. Les auteurs ont aborde cette problematique en etudiant deux tests genetiques d'Eucalyptus globulus Labill. etablis au champ depuis 10 ans en Australie. Les caracteristiques a l'etude des arbres sur pied etaient la survie, le diametre a hauteur de poitrine, la surface terriere, la rectitude de la tige et la presence de fourches. Les caracteres relies a la recolte des arbres etaient le volume, la duree de la recolte et la productivite de cette derniere. Pour ces caracteres, la variation genetique additive et de dominance au sein des groupements genetiques et entre ces derniers, la variation familiale a l'echelle du peuplement, les correlations phenotypiques et genetiques ainsi que les effets decoulant de la consanguinite ont ete estimes. Les differents scenarios etudies ont indique que la genetique avait, jusqu'a un certain point, un impact sur la productivite de la recolte des plantations et cela principalement par le biais d'une covariation positive avec le diametre de la tige. Il est donc peu probable que la productivite de la recolte ait pu etre affectee negativement par la selection passee. Alors qu'aucune variation genetique significative de nature additive ou de dominance n'a ete observee pour la presence de fourches ou la rectitude de la tige, de faibles correlations phenotypiques etaient coherentes avec la productivite de la recolte qui etait plus elevee lorsque les arbres etaient plus droits et exempts de fourches. Une depression consanguine elevee a ete observee dans le cas de la croissance et de la survie. Cependant, cela n'a entraine qu'une faible reduction de la productivite de la recolte (5,5 %) chez les descendants issus de pollinisation libre comparativement aux descendants issus de fecondation croisee. [Traduit par la Redaction] Mots-cles : productivite de la recolte, variation genetique additive, variation genetique de dominance, depression consanguine, caracteristiques des arbres sur pied., Introduction In recent decades, mechanised forest harvesting systems have been widely adopted, primarily to reduce harvest costs and improve worker safety. Time and motion studies of mechanical harvesting operations have [...]

Sustainability and globally competitive forest product supply markets are two of the pressures that forest managers face today. Both require that managers have good metrics of the quantity, quality, and location of timber resources within their forests. The value of this information must be weighed against the cost of obtaining it and losses associated with not having access to it. A cost-plus-loss procedure for assessing the relative contributions to error in estimating stand-level value recovery and log product yields was developed and tested on two Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) stands in Oregon. The sources of error were those associated with (i) market complexity, (ii) sampling intensity, (iii) stem quality assessment methods, and (iv) bucking optimization algorithms. Two performance measures were used as part of the assessment procedure: market fulfilment and the difference in total net value recovery between having complete and less than complete information. Average market fulfilment ranged between 60% and 100%. The difference in total net value recovery ranged from-21.2% to +0.8%. Stem quality assessment followed by bucking optimization algorithms and sampling intensity had the greatest effects on these performance measures. Market complexity had a negligible effect on these performance measures but affected net value recovery. La durabilite et les marches d'approvisionnement en produits forestiers competitifs a l'echelle mondiale sont deux des pressions auxquelles font face les gestionnaires forestiers de nos jours. Ces deux pressions exigent que les gestionnaires aient une bonne idee de la quantite, de la qualite et de l'emplacement de la matiere ligneuse dans leurs forets. La valeur de ces informations doit etre evaluee en tenant compte de leur cout d'acquisition et des pertes associees au fait de ne pas y avoir acces. Une analyse cout plus perte pour evaluer les contributions relatives a l'erreur dans l'evaluation de la valeur de recouvrement au niveau du peuplement et des rendements en billes a ete developpee et evaluee pour deux peuplements de douglas vert (Pseudotsuga menziesii (Mirb.) Franco) en Oregon. Les sources d'erreur etaient celles associees (i) a la comple-xite du marche, (ii) a l'intensite d'echantillonnage, (iii) aux methodes d'evaluation de qualite des tiges et (iv) aux algorithmes d'optimisation du tronconnage. Deux mesures de performance ont ete utilisees dans la procedure d'evaluation: la gestion optimale des commandes et la difference dans la valeur totale nette de recouvrement entre une situation ou l'information est complete et une autre ou l'information n'est pas complete. La valeur moyenne pour la gestion optimale des commandes se situait entre 60 % et 100 %. La difference dans la valeur totale nette de recouvrement variait de -21,2 % a 0,8 %. L'evalua-tion de la qualite des tiges, suivie par les algorithmes d'optimisation du tronconnage et l'intensite d'echantillonnage avaient le plus d'influence sur ces mesures de performance. La complexite du marche avait un effet negligeable sur ces mesures de performance, mais elle avait un effet sur la valeur totale nette de recouvrement. [Traduit par la Redaction], Introduction Two of the pressures that forest managers face today are globally competitive forest product supply markets and sustainability. Good metrics of the quantity, quality, and location of timber resources [...]

Forest management planners usually treat potential fire loss estimates as exogenous parameters in their timber production planning processes. When they do so, they do not account for the fact that forest access road construction, timber harvesting, and silvicultural activities can alter a landscape's vegetation or fuel composition, and they ignore the possibility that such activities may influence future fire losses. We develop an integrated fire and forest management planning methodology that accounts for and exploits such interactions. Our methodology is based on fire occurrence, suppression, and spread models, a fire protection value model that identifies crucial stands, the harvesting of which can have a significant influence on the spread of fires across the landscape, and a spatially explicit timber harvest scheduling model. We illustrate its use by applying it to a forest management unit in the boreal forest region of the province of Alberta in western Canada. We found that for our study area, integrated fire--forest management planning based on our methodology could result in an 8.1% increase in net present value when compared with traditional planning in which fire loss is treated as an exogenous factor. Resume: Les amenagistes forestiers considerent habituellement l'estimation des pertes potentielles causees par le feu comme un parametre exogene dans leurs processus de planification de la production de matiere ligneuse. Ce faisant, ils ne tiennent pas compte du fait que la construction de routes d'acces en foret, la coupe de bois et les travaux sylvicoles peuvent modifier la vegetation ou la composition des combustibles d'un paysage et ils ignorent la possibilite que de telles activite s puissent influencer les pertes futures causees par le feu. Nous avons developpe une methodologie integree de planification de l'amenagement forestier et de la gestion du feu qui tient compte de ces interactions et les exploite. Notre methodologie est basee sur des modeles d'occurrence, de suppression et de propagation des feux, un modele de la valeur de la protection contre le feu qui permet d'identifier les peuplements cruciaux dont la coupe peut avoir une influence significative sur la propagation des feux dans le paysage, ainsi qu'un modele spatialement explicite pour etablir le calendrier des coupes de bois. Nous illustrons son utilisation en l'appliquant a une unite d'amenagement forestier dans la region de la foret boreale de la province d'Alberta, au Canada. Dans notre aire d'etude, nous avons constate que la planification inte-gree de l'amenagement forestier et de la gestion du feu basee sur notre methodologie produisait une augmentation de 8,1 % de la valeur actualisee nette comparativement a la planification traditionnelle dans laquelle les pertes causees par le feu sont traitees comme un facteur exogene. [Traduit par la Redaction], Introduction Fire is a natural component of many forest ecosystems and is particularly important in the boreal forest region of Canada. Although fire does have beneficial impacts on many natural [...]

New sensor-based approaches for assessing the quantity, quality, and value of timber are being developed with the goals of improving the accuracy and economics of forest measurements. One new approach is based on terrestrial laser scanning (TLS). Thirty-three plots in six radiata pine (Pinus radiata D. Don) stands were scanned using TLS. Tree locations were automatically detected. Stem profiles were measured using three methods: (i) TLS scans, (ii) Atlas Cruiser inventory procedures, and (iii) manual measurement after harvesting. Stems were optimally bucked based on log specifications and prices for Australian markets. Tree values and log product yields were estimated for the TLS data and compared with estimates based on Cruiser and actual manual measurements of stem profiles. TLS volume and value recovery were within 8% and 7%, respectively, of actual harvester recovery for five of the six stands in which it was used. Cruiser volume and value estimates were both within 4% of actual harvester recovery. Plot preparation procedures, tree characteristics, and taper equations used to model diameters on hidden stem sections affected the accuracy of automated stem detection and profile measurements for the TLS system. Improvements in data capture and analytical procedures should improve the accuracy of TLS-based volume and value estimates. Resume: Dans le but d'ameliorer la precision et l'economie des mesures dendrometriques, de nouvelles approches basees sur les capteurs sont en cours d'elaboration pour evaluer la quantite, la qualite et la valeur du bois. Une nouvelle approche est basee sur le balayage laser terrestre (BLT). Trente trois placettes etablies dans six peuplements de pin de Monterey (Pinus radiata D. Don) ont ete numerisees par BLT. L'emplacement des arbres a ete detecte automatiquement. Le defilement des tiges a ete mesure en utilisant trois methodes: (i) le BLT, (ii) l'inventaire Atlas Cruiser et (iii) la mesure reelle apres la coupe. Les tiges ont ete tronconnees de maniere optimale a l'aide des specifications des billes de bois et des prix du bois sur les marches australiens. La valeur des arbres et le rendement des produits de transformation des billes ont ete estimes par BLT et compares aux estimations basees sur l'inventaire Atlas Cruiser et aux mesures reelles du defilement. Les estimations du volume par BLT et de la valeur des produits de transformation ne depassaient pas respectivement 8 et 7 % des resultats reels de l'abatteuse pour cinq des six peuplements ou le BLT a ete utilise. Les estimations du volume et de la valeur des produits de transformation basees sur l'inventaire Atlas Cruiser ne depassaient pas 4 % des resultats reels de l'abatteuse. Les procedures de preparation des placettes, les caracteristiques des arbres et les equations du defilement utilisees pour predire le diametre des sections de tige cachees par les arbres voisins ont affecte la precision de la detection automatique des tiges et la mesure du defilement dans le cas du BLT. L'amelioration de la saisie des donnees et des proce dures d'analyse devrait ameliorer la precision de l'estimation du volume et de la valeur du bois par BLT. [Traduit par la Redaction], Introduction Good metrics of the quantity, quality, and location of timber resources within each forest are essential for ensuring that wastage is minimized, harvest and volume growth increments are balanced, [...]

High-resolution unmanned aerial vehicle (UAV) multi-spectral sensor images can provide valuable information for mapping forest areas that have recently been burned. In this study, we investigate the use of multi-spectral images captured with a UAV to evaluate burn severity in areas affected by forest fires in Gumi-si, South Korea. Fire classification was performed using two supervised learning algorithms, maximum likelihood (ML) and spectral angle mapper (SAM). Three spectral indices, namely, normalized difference vegetation index (NDVI), RedEdge NDVI (RE-NDVI), and the visible-band difference vegetation index (VDVI), were used to create burn severity thresholds in ML and SAM classifiers. The classification results indicated that ML has higher overall accuracy (80-89%, Kappa coefficient = 0.8) than SAM (44-52%, Kappa coefficients ~0.27) in identifying fire severity classes. The ML classifier showed higher accuracy for both unburned and crown fire classes, whereas the SAM classifier exhibited moderate accuracy for all classes. Most of the misclassification was identified between the unburned area and the low heat-damaged area. This research revealed that distinguishing between the unburned area and low heat-damaged area is the most challenging task in fire severity classification. Also, further investigation is required to improve the accuracy of fire severity classification from multi-spectral images. [ABSTRACT FROM AUTHOR]

Investment in thinning as part of forest management is generally for one of three purposes: improved future stand growth and quality to produce higher value products for later final harvest, removal of fuels to reduce fire risk or to meet ecological goals such as increasing biodiversity. The focus of this paper is on the thinning operations in Australian pine and eucalypt plantations, which are almost exclusively conducted by harvester-processors and forwarders. The Australian Forest Operations Research Alliance (AFORA) has conducted research projects on assessing the productivity of harvester-processors and forwarders in pine and eucalypt plantations in different sates/regions. All-time study data collected in different case studies have been consolidated into a data base called ALPACA (Australian Logging Productivity and Cost Appraisal). The data were used to develop the general productivity predicting models for harvester and forwarder based on multiple regression modelling. Harvester productivity was mainly a function of tree volume. Forwarder productivity was primarily a function of extraction distance. Slope has been included in the models as a weighting factor based on three classes and namely <15%, from 15% to 25% and >25%. [ABSTRACT FROM AUTHOR]