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Wildland fires have a multitude of ecological effects in forests, woodlands, and savannas across the globe. A major focus of past research has been on tree mortality from fire, as trees provide a vast range of biological services. We assembled a database of individual-tree records from prescribed fires and wildfires in the United States. The Fire and Tree Mortality (FTM) database includes records from 164,293 individual trees with records of fire injury (crown scorch, bole char, etc.), tree diameter, and either mortality or top-kill up to ten years post-fire. Data span 142 species and 62 genera, from 409 fires occurring from 1981-2016. Additional variables such as insect attack are included when available. The FTM database can be used to evaluate individual fire-caused mortality models for pre-fire planning and post-fire decision support, to develop improved models, and to explore general patterns of individual fire-induced tree death. The database can also be used to identify knowledge gaps that could be addressed in future research.

Red turpentine beetle, Dendroctonus valens LeConte (Coleoptera: Curculionidae: Scolytinae), previously responded more strongly to (−)‐β‐pinene + ethanol than (+)‐3‐carene + ethanol lures at sites burned the prior year by wildfire in Oregon and northeastern California, whereas at a thinned‐unburned Arizona site (+)‐3‐carene + ethanol was the stronger attractant. This discrepancy was further examined to tease apart whether D. valens attraction varies by region or previous forest disturbance types.Here, (−)‐β‐pinene + ethanol and (+)‐3‐carene + ethanol lures were tested in pine stands at two Oregon sites disturbed the previous year by a prescribed burn or thinning only. Both lures were tested also with or without trace amounts of the pheromone frontalin, as its presence enhanced attractions in China but had not been tested in North America.At both sites, regardless of prior forest disturbance, (−)‐β‐pinene + ethanol lures attracted the most beetles. Lures releasing trace frontalin attracted more beetles than their corresponding lures without it at both sites, except in one case.Overall, previous year disturbances from disparate management treatments had minimal influence on lure attraction to D. valens. For detection, monitoring or management (−)‐β‐pinene + ethanol + frontalin in trace amounts attracts the most beetles of lures tested to date in Pacific Northwest pine forests. [ABSTRACT FROM AUTHOR]

Lure attraction strength for red turpentine beetle, Dendroctonus valens (Coleoptera: Curculionidae: Scolytinae) observed previously in US Pacific Northwest ponderosa pine forests is (−)‐β‐pinene+ethanol > (+)‐3‐carene+ethanol, but untested elsewhere in its western US range. Thus, both were tested with (−)‐β‐pinene, (+)‐3‐carene, ethanol, and a blank in Oregon and California sites burned by wildfire, whereas in Arizona the first four lures were tested in a thinned‐unburned site.The D. valens responses in burned Oregon and California sites were similar, (−)‐β‐pinene+ethanol > (−)‐β‐pinene > 3‐carene = 3‐carene+ethanol > ethanol > blank, whereas in the cut‐unburned Arizona site it was 3‐carene+ethanol > 3‐carene = (−)‐β‐pinene+ethanol > (−)‐β‐pinene. Whether this variation was influenced by beetle genetic differences, or chemical and physical parameters in the different environments and remaining stressed host resources 1‐year post disturbance warrants additional study.Responses to (−)‐β‐pinene varied, from a stronger attractant than (+)‐3‐carene in Oregon and California, to a weaker lure than (+)‐3‐carene in Arizona. This (−)‐β‐pinene variability was minimized when released in combination with ethanol, making (−)‐β‐pinene+ethanol the most consistent attractant of those tested across the three states, and a reliable lure for detection, monitoring, and management projects for D. valens in western US pine forests. [ABSTRACT FROM AUTHOR]

Current knowledge concerning the interactions between forest disturbances such as fire and insect defoliation is limited. Wildfires and prescribed burns may influence the intensity and severity of insect outbreaks by affecting the vigor of residual trees, altering aspects of stand structure and abundance of preferred hosts, and by changing the physical environment within forest stands. Prescribed burn timing and frequency are particularly important aspects of the fire regime to consider because they can alter numerous aspects of tree vigor, stand structure, and environmental conditions, and can be manipulated by managers. We evaluated ponderosa pine (Pinus ponderosa Douglas ex P. Lawson & C. Lawson) defoliation patterns in relation to season (fall and spring) and interval (5 or 15 years) of prescribed burn in the southern Blue Mountains of Oregon. Beginning in 2008 a pine butterfly (Neophasia menapia C. Felder & R. Felder) (Lepidoptera: Pieridae) outbreak coincided with a long-term experimental study, providing a unique opportunity to address this question. Defoliation patterns were measured in 2012. The 5 year interval plots had burned three times with five growing seasons of recovery and the 15 year interval plots had burned once with 15 growing seasons of recovery. Mean pine butterfly defoliation across the study area was about 71%. We found a significant interaction between season of burn and interval of burn on defoliation. Areas burned in the fall every 5 years had marginally less (about 5%) defoliation compared with areas that were burned in the fall 15 years previous. Regression tree analysis revealed that defoliation patterns varied based on stand location, percent mortality since the start of the experiment, and tree height. Our results show that (i) season of burn and interval of burn did not predispose these stands to increased defoliation during a pine butterfly outbreak and (ii) repeat burning may actually lead to lower defoliation. However, the effect we document is small and only marginally significant. Resume: Les connaissances actuelles au sujet des interactions entre les perturbations de la foret, telles que le feu et la defoliation par les insectes, sont limitees. Les feux de foret et les brulages diriges peuvent influencer l'intensite et la severite des epidemies d'insecte. A cause de leur impact sur la vigueur des arbres residuels, ils peuvent modifier les aspects de la structure du peuplement et l'abondance des hotes preferes et changer l'environnement physique a l'interieur des peuplements forestiers. La frequence des brulages diriges et le moment ou ils sont effectues sont des aspects particulierement importants du regime des feux a prendre en compte parce qu'ils peuvent alterer plusieurs aspects de la vigueur des arbres, de la structure des peuplements et des conditions environnementales et peuvent etre manipules par les amenagistes. Nous avons evalue les schemas de defoliation du pin ponderosa (Pinus ponderosa Douglas ex P. Lawson & C. Lawson) en fonction de la saison (automne ou printemps) et de la periode de recurrence (5 ou 15 ans) des brulages diriges dans le sud des montagnes Bleues en Oregon. A partir de 2008, une epidemie de pieride du pin (Neophasia menapia C. Felder & R. Felder) (Lepidoptera: Pieridae) qui coincidait avec une etude experimentale a long terme a fourni une occasion unique de s'attaquer a cette question. Les schemas de defoliation ont ete mesures en 2012. Les placettes associees a l'intervalle de 5 ans avaient brule trois fois et recupere pendant cinq saisons de croissance et les placettes associees a l'intervalle de 15 ans avaient brule une fois et recupere pendant 15 saisons de croissance. Le taux moyen de defoliation par la pieride du pin dans l'ensemble de l'aire d'etude etait d'environ 71 %. Nous avons trouve une interaction significative entre la saison ou a eu lieu le brulage et l'intervalle entre les brulages dans le cas de la defoliation. Les zones brulees a l'automne a tous les 5 ans avaient subi legerement moins (environ 5 %) de defoliation que les zones brulees a l'automne 15 ans auparavant. L'analyse de l'arbre de regression a revele que les schemas de defoliation variaient selon l'endroit ou se trouvait un peuplement, le pourcentage de mortalite depuis le debut de l'experience et la hauteur des arbres. Nos resultats montrent que (i) la saison ou a eu lieu le brulage et l'intervalle de temps entre les brulages n'ont pas predispose ces peuplements a une defoliation plus severe lors d'une epidemie de pieride du pin et (ii) les brulages repetes peuvent en fait reduire la defoliation. Cependant, l'effet que nous avons note est faible et seulement legerement significatif. [Traduit par la Redaction], Introduction The pine butterfly (Neophasia menapia (C. Felder & R. Felder)) (Lepidoptera: Pieridae) occurs in pine and Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) forests throughout western North America. This butterfly is [...]

Lure efficacy for primary attraction of red turpentine beetle, Dendroctonus valens (Coleoptera: Curculionidae: Scolytinae) observed previously in US Pacific Northwest ponderosa pine forests is (−)‐β‐pinene+ethanol > (+)‐3‐carene+ethanol > (+)‐α‐pinene+ethanol.Influence of (−)‐β‐pinene+ethanol release rates was tested with nine lures representing all combinations of three release levels for each compound in a 3 × 3 factorial design field test in Oregon. Beetle catch had a positive, linear relationship with the combined (−)‐β‐pinene+ethanol total release (or dose), resulting from higher release of either one or both compounds. Reversing component ratios, that is, 1 : 2 versus 2 : 1 with similar total doses, produced minimal changes in beetle response.Females produce frontalin with dual aggregation and sex‐pheromone functions. In another test, high‐release frontalin, defined as >1.0 mg/day release, was tested at 1.4 to 1.5 mg/day in combination with each monoterpene+ethanol lure above and their trap catch compared with (−)‐β‐pinene+ethanol lures. Presence of high‐release frontalin produced minimal changes in beetle responses. [ABSTRACT FROM AUTHOR]

In US Pacific Northwest ponderosa pine forests the primary attraction order shown previously for red turpentine beetle, Dendroctonus valens (Coleoptera: Curculionidae: Scolytinae), is (−)‐β‐pinene+ethanol > (+)‐3‐carene+ethanol > (+)‐α‐pinene+ethanol. The monoterpenes are bicyclic C10H16 isomers containing one 6‐carbon ring with one double bond. Both pinenes have a 4‐carbon second ring and differ only by their endocyclic or exocyclic double bond. The (+)‐3‐carene second ring has 3‐carbons; its double bond is endocyclic like (+)‐α‐pinene.Ring system and double bond influences on primary attraction were evaluated by hydrogenating (+)‐3‐carene and (+)‐α‐pinene to cis‐carane and cis‐pinane, respectively. Field test primary attraction strengths were (−)‐β‐pinene+ethanol > cis‐carane+ethanol > cis‐pinane+ethanol > ethanol.In combination with ethanol (i) a double bond is not required in either ring system to attract D. valens, (ii) the cis‐carane bicyclic 3, 6‐carbon ring system provides stronger beetle attraction than the cis‐pinane 4, 6‐carbon bicyclic ring system, and likely structural basis for stronger (+)‐3‐carene attraction over (+)‐α‐pinene, (iii) adding an exocyclic double bond to the 4, 6‐carbon ring system elevates attraction above the 3, 6‐carbon ring system with no double bond, and (iv) the 4, 6‐carbon ring system is a much stronger attractant with an exocyclic rather than endocyclic double bond. [ABSTRACT FROM AUTHOR]

Abstract: Red turpentine beetle Dendroctonus valens LeConte is a non‐aggressive bark beetle in North America that attacks weakened or recently dead pines, as well as their fresh logs or stumps. Fire‐injured ponderosa pines releasing stress‐induced ethanol are often attacked. The oleoresin from these trees frequently contains 3‐carene as a major component mixed with α‐ or β‐pinene. 3‐Carene lures usually attract more D. valens than α‐ or β‐pinene lures or 1 : 1 : 1 mixtures, whereas the attraction of ethanol + 3‐carene lures has never been tested. Funnel traps with ethanol, 3‐carene or ethanol + 3‐carene lures, and a no lure blank, were set‐up as a randomized complete block design in a pine forest near La Pine, Oregon, U.S.A., from 23 April until 11 June 2015. Dendroctonus valens, Hylastes nigrinus, Hylurgops reticulatus, Hylurgops porosus and Hylastes gracilis exhibited similar responses, with highest numbers captured in traps with ethanol + 3‐carene. The response by the first three species was confirmed as synergistic. Ips spp., Pityogenes spp., Gnathotrichus spp., Pachysquamus subcostulatus and Hylastes macer composed a second group whose numbers captured with ethanol lures were similar or greater than the 3‐carene or ethanol + 3‐carene lures. A reduced H. macer response to ethanol + 3‐carene was confirmed as an interruption. [ABSTRACT FROM AUTHOR]

Prescribed burning is used to reduce fuel loads and to return fire to its historic disturbance role in western forests. Managers need to know the effects of prescribed fire on tree growth. Growth of residual ponderosa pine (Pinus ponderosa Dougl. ex Laws.) was measured in an existing long-term study of the effects of season-of-prescribed burn in combination with a single or a repeated burn. Each of six previously thinned mixed-age stands in the Blue Mountains near Burns, Oregon, was subdivided into three experimental units, and one of three treatments was randomly assigned to each: fall 1997 burn, spring 1998 burn, and no burn (control). Treatments were operational-sized prescribed burns. In 2002/2003 each burned unit was split, and one-half was burned again, maintaining the original season of burn. Sample trees were evaluated for growth 5 and 10 seasons after the initial prescribed fires. We conclude that after accounting for ihe crown scorch proportion neither a single spring or fall prescribed fire treatment nor a repeated fire treatment 5 years later affected the growth of thinned ponderosa pine 10 years after the initial 1997/1998 fires. A linear regression is included to estimate bark thickness based on dbh. [ABSTRACT FROM AUTHOR]