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Woodwasps in Sirex and related genera are well-represented in North American conifer forests, but the chemical ecology of native woodwasps is limited to a few studies demonstrating their attraction to volatile host tree compounds, primarily monoterpene hydrocarbons and monoterpene alcohols. Thus, we systematically investigated woodwasp-host chemical interactions in California's Sierra Nevada and West Virginia's Allegheny Mountains. We first tested common conifer monoterpene hydrocarbons and found that (-)-α-pinene, (+)-3-carene, and (-)-β-pinene were the three most attractive compounds. Based on these results and those of earlier studies, we further tested three monoterpene hydrocarbons and four monoterpene alcohols along with ethanol in California: monoterpene hydrocarbons caught 72.3% of all woodwasps. Among monoterpene hydrocarbons, (+)-3-carene was the most attractive followed by (-)-β-pinene and (-)-α-pinene. Among alcohols, ethanol was the most attractive, catching 41.4% of woodwasps trapped. Subsequent tests were done with fewer selected compounds, including ethanol, 3-carene, and ethanol plus (-)-α-pinene in both Sierra Nevada and Allegheny Mountains. In both locations, ethanol plus (-)-α-pinene caught more woodwasps than other treatments. We discussed the implications of these results for understanding the chemical ecology of native woodwasps and invasive Sirex noctilio in North America. In California, 749 woodwasps were caught, representing five species: Sirex areolatus Cresson, Sirex behrensii Cresson, Sirex cyaneus Fabricius, Sirex longicauda Middlekauff, and Urocerus californicus Norton. In West Virginia 411 woodwasps were caught representing four species: Sirex edwardsii Brullé, Tremex columba Linnaeus, Sirex nigricornis F., and Urocerus cressoni Norton.

Four 10- to 20-year-old plantations were precommercially thinned to determine the effects on tree growth and mortality caused by armillaria and heterobasidion root diseases. The plantations represented different species compositions with one each of (1) coastal Douglas-fir and noble fir, (2) Douglas-fir and western hemlock, (3) pure Douglas-fir, and (4) Shasta red fir and mountain hemlock. After 30 years, the probabilities of leave-tree survival and actual leave-tree survival (trees/ha [TPH]) were significantly (P ≤ 0.05) higher in thinned versus unthinned plots in one of the four plantations with no significant differences in the other three plantations. Most tree mortality was caused by armillaria root disease. Despite the high frequency of Heterobasidion occidentale in overstory stumps, only two leave trees in one plantation were killed by this fungus after 30 years. Quadratic mean diameter (QMD) growth and basal area (BA) (per ha) growth of leave trees were significantly (P ≤ 0.05) greater in thinned than in unthinned plots in one plantation for QMD and in three plantations for BA. Precommercial thinning does not appear to exacerbate the incidence of leave-tree mortality from armillaria or heterobasidion root diseases after 30 years, and leave-tree QMD and BA growth increased significantly in most but not all plantations for the tree species sampled. Armillaria and heterobasidion root diseases are not an impediment to precommercial thinning in plantations or stands similar to those we studied.

With 27 years of data (1986–2012), we examined long-term patterns of variation in abundance and population trends for 35 species of oak woodland birds. Following a standardized protocol, from three to eight observers counted birds annually at 210 count stations at the San Joaquin Experimental Range, Madera County, California. We used both linear regression and nonparametric regression (spline-smoothing the year effect) to evaluate population trends. The abundance of most species varied greatly over the study period, emphasizing the importance of long-term monitoring. Overall, 12 species increased: the California Quail (Callipepla californica), Anna’s Hummingbird (Calypte anna), Red-tailed Hawk (Buteo jamaicensis), Acorn Woodpecker (Melanerpes formicivorus), Nuttall’s Woodpecker (Picoides nuttallii), American Kestrel (Falco sparverius), Common Raven (Corvus corax), Violet-green Swallow (Tachycineta thalassina), White-breasted Nuthatch (Sitta carolinensis), Bewick’s Wren (Thryomanes bewickii), European Starling (Sturnus vulgaris), and House Finch (Haemorhous mexicanus). Five species decreased: the California Scrub-Jay (Aphelocoma californica), Blue-gray Gnatcatcher (Polioptila caerulea), Western Bluebird (Sialia mexicana), Western Meadowlark (Sturnella neglecta), and Bullock’s Oriole (Icterus bullockii). Of these, the Blue-gray Gnatcatcher, Western Meadowlark, and Bullock’s Oriole present cause for concern. We recommend further research to elucidate the causes for the declines of these three species. We also recommend continued monitoring of the California Scrub-Jay and Western Bluebird to verify recovery to previous levels of abundance. Our results emphasize the need for long-term monitoring of avian populations, which will provide insights into population dynamics and may reveal negative trends that may require conservation action.

Using 27 years of point count data collected at the San Joaquin Experimental Range, Madera County, California, we modeled the importance of weather and climate variables on annual variability in the abundance of 35 bird species, to assess the potential responses of birds to changing environmental conditions. We used semi-parametric Poisson generalized additive models (GAM) with smoothing functions to explore relationships between bird abundance and the independent climatic and weather variables and to extract the best parametric polynomial model. We then selected among three parametric generalized linear mixed models (Poisson, quasi-Poisson, and negative binomial) on the basis of how well they explained the overdispersion of the counts. This approach also allowed us to estimate and control for variability among observers. Temperature variables were important in explaining variation in bird abundance. More species responded to cold than to hot temperatures: 18 were sensitive to cold, or were more abundant following warm winters or springs, whereas only 4 species were sensitive to heat. Because minimum temperatures are increasing faster than maximum temperatures, species sensitive to cold may benefit from warming. Abundance of Anna’s Hummingbirds (Calypte anna), California Scrub-Jays (Aphelocoma californica), Oak Titmice (Baeolophus inornatus), and Bewick’s Wrens (Thryomanes bewickii) decreased with warm temperatures, so an increase in mean temperatures is likely to affect these species negatively. One species, the Turkey Vulture (Cathartes aura), was more abundant after hot summers. Response to precipitation varied, with the number of species that increased in abundance with increasing precipitation being roughly equal to the number that decreased. El Niño Southern Oscillation (ENSO) events are predicted to increase in frequency and severity with climate change. The effects of ENSO vary geographically; for example, species that occur at lower elevations appear to respond differently from those that breed at higher elevations, where winter precipitation is dominated by snow rather than rain. In our low-elevation study area 12 species responded positively to warm, wet El Niño conditions; only 4 responded negatively. We found no clear pattern of response to long-term variation related to the Pacific Decadal Oscillation (PDO). We identified four species that decreased following drought years, but one of these, the Red-tailed Hawk (Buteo jamaicensis), was primarily responding (positively) to wet years. Abundance of Nuttall’s Woodpeckers (Picoides nuttallii), Canyon Wrens (Catherpes mexicanus), and Lesser Goldfinches (Spinus psaltria) decreased with drought, so these species should be negatively affected by the increased frequency and severity of droughts projected with climate change. Oak woodland birds are closely tied to oaks and the acorns they produce, but questions about the ability of oaks to shift upward in elevation and latitude raise doubts about the ability of these bird species to adapt to climate change. Long-term monitoring data are useful for investigating and predicting avian responses to climate change. Understanding potential responses will help inform conservation decisions and planning for an uncertain future. We hope our predictions for how California oak woodland birds may respond to the changing climate will help prioritize future research and facilitate conservation.

A single strain of Puccinia psidii, the causal agent of rust disease on Myrtaceae, was recently reported on multiple myrtaceous hosts in Hawai‘i, but this strain has caused only mild levels of damage to the state’s predominantn ative forest tree, ‘öhi‘a ( etrosideros polymorpha). Multiple other strains of Puc­ Mcinia psidii have been identified from Brazil and characterized via extensive sampling and microsatellite analyses. Potential effects of other Brazilian P. psidii strains on Hawai‘i’s ‘öhi‘a were investigated with two inoculation experiments conducted in Brazil. The first, a split-plot experiment, was conducted to deter- mine pathological impact of five Brazilian P. psidii strains on ‘öhi‘a seedlings and to assess variation in susceptibility of seedlings from six different open-­ ollinatedp ‘öhi‘a parent trees to each P. psidii strain. The second experiment was conducted to determine influence of the rust disease on growth and survival of ‘öhi‘a seedlings. Three of the five P. psidii strains were highly virulent on most of the inoculated ‘öhi‘a seedlings (93% 00% infection rates), and none of the ‘öhi‘a–1 families used in this test showed significant resistance. The other two strains tested were much less virulent. Infection by the highly virulent strains of P. psidii resulted, on average, in a 69% reduction in height growth and 27% increase in mortality of ‘öhi‘a seedlings at 6 months postinfection. These results have immediate implications for designing Hawai‘i’s quarantine barriers.

California coast live oaks ( Quercus agrifolia Nee) have suffered large losses from sudden oak death, caused by the introduced oomycete Phytophthora ramorum . Infected mature coast live oaks exhibit cankers on the main stem that produce a viscous sap-derived exudate, referred to as bleeding. Subsequent attacks by ambrosia and bark beetles, followed by the activity of fungi introduced by these insects, have led to mortality levels greater than 50% since the mid-1990s. Despite an infection rate of 5% year −1 , asymptomatic trees still persist in many heavily infected stands after more than 15 years of exposure to the pathogen. We hypothesized that varying responses to P. ramorum , including apparent recovery from infections, reflected phenotypic differences in susceptibility. In this study we evaluated the relationship between the early development of symptoms in mature trees that were experimentally inoculated with P. ramorum and long-term survival. A logit model showed that external canker lengths measured 9 months following inoculation predicted survival 7 years later. We defined resistance to P. ramorum in the surviving trees as absence or cessation of bleeding after the 7 years of the study and absence of beetle attacks on bleeding trees. Probability of resistance was also predicted by external canker length measured 9 months after inoculation. Canker length distribution was consistent with quantitative resistance to P. ramorum . The role of plant chemistry in resistance was examined by quantifying soluble phenolics in phloem methanol extracts prepared from the surviving trees. A logistic regression model found that expression of resistance was associated with four phenolic compounds; ellagic acid and a partially characterized ellagic acid derivative, and two chromatographic peaks that represent two uncharacterized phenolic compounds. Ellagic acid and a crude methanol extract from coast live oak phloem (total phenolics) were fungistatic when assayed in vitro at physiologically relevant levels and total phenolics were fungicidal at the highest concentration tested. The association of certain phenolics with resistance may facilitate the use of biomarkers in minimally invasive assays to predict the response of trees to P. ramorum , thereby increasing the options for managing threatened forests.

In interior Alaska, increased use of mechanical fuel reduction treatments, increased interests in the use of wood energy systems as alternatives to fossil fuels, and elevated populations of northern spruce engraver, Ips perturbatus (Eichhoff), have raised concerns regarding the impact of this bark beetle to forest resources. We conducted a large-scale field study in 2009−2011 (Study 1) to determine the effects of slash scoring (mechanical by chainsaw versus none), slash distribution (scattered versus decked), and cutting date (spring versus fall) on I. perturbatus colonization of and reproductive performance in white spruce, Picea glauca (Moench) Voss, slash, and to determine the effects of resulting treatments on adjacent levels of tree mortality caused by I. perturbatus. Unfortunately, attack densities were lower than expected, and did not provide for a very robust examination of the effects of these treatments. As a result, we reproduced several aspects of Study 1 in a second study (2011) using a baited design. Higher levels of I. perturbatus attack and emergence occurred on dispersed logs. Attack densities were highest in the dispersed, unscored treatment, and ∼70% higher than observed in the decked, scored treatment. The scoring of dispersed logs significantly reduced attack densities by ∼28%, but had no effect in decked treatments or on levels of emergence in either treatment. Higher levels of attack and emergence were observed on the tops of logs as compared to the bottoms of logs. Brood production (i.e., defined here as emergence/attacks) was also greater on the tops of logs compared to the bottoms of logs, suggesting the tops of logs are not only more attractive to I. perturbatus, but confer some advantage to brood development. Lower levels of attack and emergence occurred on small diameter logs. Higher levels of attack and emergence were observed on logs in a shaded fuelbreak (i.e., a more open condition of lower tree density) compared to the adjacent forest. Overall, our research suggests that unlike other works on Ips spp. in the western USA that promote the desiccation of slash to minimize colonization and brood production, I. perturbatus appears regulated by the apparency and accessibility of host material. This finding highlights the importance of developing management guidelines based on local science. A third study found two semiochemicals, trans-conophthorin and verbenone, reduced colonization of slash by I. perturbatus, and therefore holds promise as a tool for managing I. perturbatus populations. The implications of these and other results to the management of I. perturbatus in interior Alaska are discussed.

A critical component of a growth and yield simulator is an estimate of mortality rates. The mortality models presented here are developed from long-term permanent plots in provinces from throughout the geographic range of ponderosa pine in the United States extending from the Black Hills of South Dakota to the Pacific Coast. The study had two objectives: estimation of the probability of a tree survival for the next 5 years and the probability of a tree surviving longer than a given time period (survival trend) for a given set of covariates. The probability of a tree surviving for the next 5 years was estimated using a logistic model regressed on 18 covariates measured 5 years before the last measurement period with 15 smoothing variables (S1–S15) for spatial effects of latitude and longitude surface. The fitted model showed that the probability of survival increased with increasing diameter at breast height (DBH), DBH periodic annual increment (PAIDBH) and increasing plot basal area/number of trees per hectare (PBAH/TPH), and decreased with increasing average of the 5 tallest trees in the plot (AVGHT5) when other selected covariates were included in the model. The probability of a tree surviving longer than a given time period was estimated by fitting the Cox Proportional Hazard model to the last observed survival period regressed on 13 covariates measured at the first measurement period. This probability also increased with increasing DBH and PAIDBH, and decreased with increasing AVGHT5. The Akaike’s Information Criterion (AIC) and graphs of partial residuals were used in the selection of covariates included in the models.

DISRUPT Micro-Flake Verbenone Bark Beetle Anti-Aggregant flakes (Hercon Environmental, Inc., Emigsville, Pennsylvania) were applied in two large-scale tests to assess their efficacy for protecting whitebark pine Pinus albicaulis Engelm. from attack by mountain pine beetle Dendroctonus ponderosae Hopkins (Coleoptera: Scolytinae) (MPB). At two locations, five plots of equivalent size and stand structure served as untreated controls. All plots had early- to mid-outbreak beetle populations (i.e. 7.1-29.2 attacked trees/ha). Verbenone was applied at 370 g/ha in both studies. Intercept traps baited with MPB aggregation pheromone were placed near the corners of each plot after the treatment in order to monitor beetle flight within the plots. Trap catches were collected at 7- to 14-day intervals, and assessments were made at the end of the season of stand structure, stand composition and MPB attack rate for the current and previous years. 2 Applications of verbenone flakes significantly reduced the numbers of beetles trapped in treated plots compared with controls at both sites by approximately 50% at the first collection date. 3 The applications also significantly reduced the proportion of trees attacked in both Wyoming and Washington using the proportion of trees attacked the previous year as a covariate in the model for analysis of current year attack rates; in both sites, the reduction was ≥ 50%. 4 The flake formulation of verbenone appears to have promise for area-wide treatment by aerial application when aiming to control the mountain pine beetle in whitebark pine forests.

BACKGROUND: The mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae, Scolytinae), is the most destructive bark beetle in western North America. Dendroctonus ponderosae can be prevented from successfully colonizing and killing individual trees by ground-based sprays of insecticides applied directly to the tree bole. However, the future availability of several active ingredients, including carbaryl which is most commonly used in the western United States, is uncertain. Two novel insecticides, cyantraniliprole [Cyazypyr™-OD (oil dispersion) and Cyazypyr™-SC (suspension concentrate)] and chlorantraniliprole (Rynaxypyr®), and carbaryl were assayed in both filter paper and topical assays. RESULTS: Compared with 20 000 mg L−1 carbaryl (i.e. the maximum label rate for solutions applied to conifers for protection from bark beetle attack in the western United States), cyantraniliprole OD caused similar rates of mortality in D. ponderosae adults at 400-fold weaker concentrations in both bioassays, while cyantraniliprole SC caused similar rates of mortality at 40-fold weaker concentrations. Probit analyses confirmed that D. ponderosae is most sensitive to cyantraniliprole OD, while chlorantraniliprole was effective at concentrations similar to carbaryl. CONCLUSIONS: These results suggest that lower concentrations of carbaryl have merit for field testing than have been previously considered. While cyantraniliprole and chlorantraniliprole have similar modes of action, cyantraniliprole OD appears to have greater promise for protecting individual trees from mortality attributed to D. ponderosae attack and should be evaluated in field studies. Published 2011 by John Wiley & Sons, Ltd.

One of the primary assumptions associated with many wildlife and population trend studies is that target species are correctly identified. This assumption may not always be valid, particularly for species similar in appearance to co-occurring species. We examined size overlap and identification error rates among Cooper's (Accipiter cooperii) and sharp-shinned (A. striatus) hawks specific to a raptor migration count station along the Pacific Coast of North America. Illustrating the difficulty of distinguishing between these 2 species, we found overlap in 7 metrics among species–sex groups and in 2 metrics between species, and a principal components analysis revealed a continuum of discrete clusters for each species–sex combination in morphospace. Among juvenile hawks (n = 940), we found the greatest misidentification rate for male Cooper's hawks (23% of the 156 males were identified as sharp-shinned), lesser error rates for female Cooper's (8%, n = 339) and female sharp-shinned (6%, n = 246)...

Summary • Recent studies have investigated the relationships between pairs or groups of exotic species to illustrate invasive mechanisms, but most have focused on interactions at a single trophic level. • Here, we conducted pathogenicity tests, analyses of host volatiles and fungal growth tests to elucidate an intricate network of interactions between the host tree, the invasive red turpentine beetle and its fungal associates. • Seedlings inoculated with two strains of Leptographium procerum isolated from Dendroctonus valens in China had significantly longer lesions and higher mortality rates than seedlings inoculated with other fungal isolates. These two strains of L. procerum were significantly more tolerant of 3-carene than all other fungi isolated there, and the infection of Chinese pine (Pinus tabuliformis) seedlings by these two strains enhanced the production and release of 3-carene, the main attractant for D. valens, by the seedlings. • Our results raise the possibility that interactions among the fungal associates of D. valens and their pine hosts in China may confer advantages to these strains of L. procerum and, by extension, to the beetles themselves. These interactions may therefore enhance invasion by the beetle–fungal complex.

Sudden oak death, caused byPhytophthora ramorum, is widely established in mesic forests of coastal central and northern California. In 2000, we placed 18 plots in two Marin County sites to monitor dis- ease progression in coast live oaks (Quercus agrifolia), California black oaks (Q. kelloggii), and tanoaks (Lithocarpus densiflorus), the species that are most consistently killed by the pathogen in these areas. Through early 2008, the numbers of newly infected trees increased for all species. The infection rate for trees that were asymptomatic in 2000 was 5.0%y "1 for coast live oaks, 4.1%y "1 for black oaks and

The fisher (Martes pennanti) is a forest mustelid endemic to North America that has experienced range reductions in Pacific states that have led to their listing under the Endangered Species Act as warranted but precluded by higher priorities. The viability of the southern Sierra Nevada fisher population is of particular concern due to its reduced historical range, isolated nature, and low genetic variability. We located resting structures of radio-collared fishers in the southern Sierra Nevada and compared resting and available habitat to examine selection for specific features of resting sites. Resting structures provide protection from predators and unfavorable weather and are believed to be the most limiting habitat element across fisher home ranges. Resting structures were found primarily in live trees (76%) and snags (15%). Trees used by fishers for resting were among the largest available and frequently had mistletoe infestations. Ponderosa pines (Pinus ponderosa) were used more often than expected and incense cedars (Calocedrus decurrens) less than expected. Snags were also large and in fairly advanced stages of decay. Habitat at fisher resting sites had higher canopy cover, greater basal area of snags and hardwoods, and smaller and more variable tree sizes compared to random sites. Resting sites were also found on steeper slopes and closer to streams. Canopy cover was consistently the most important variable distinguishing rest and random sites. In western North America, fishers are generally associated with late-successional forests, but changes in these forests due to logging and fire suppression have resulted in a transition to forest stands characterized by fewer large trees and more small stems. These conditions are consistent with our finding that the large rest structures were surrounded by smaller than average trees. Management practices that support the growth and retention of greater numbers of large trees and snags, while maintaining a minimum of 61% (based on moosehorn) or 56% (generated via Forest Vegetation Simulator) canopy cover and a complex horizontal and vertical forest structure, can improve and provide for future fisher habitat.

We tested a new formulation of verbenone, an antiaggregation pheromone of the mountain pine beetle (Dendroctonus ponderosae Hopkins) (Coleoptera: Curculionidae: Scolytinae), for area-wide protection of lodgepole pine (Pinus contorta Douglas ex Loudon) stands in the western United States. Helicopter applications of verbenone-releasing laminated flakes were made at the rate of 370 g of active ingredient/ha to two sites, one in California and one in Idaho, during summer 2005. Each site consisted of five 20.23-ha treated plots and five matching 20.23-ha untreated plots. We assessed D. ponderosae flight into study plots using traps baited with aggregation pheromones and we tallied D. ponderosae attack rates on P. contorta trees in treated and control plots before and after application. There were no significant differences between numbers of D. ponderosae trapped on treated and control plots. However, a significantly smaller proportion of P. contorta trees was attacked in treated plots than in control plots at both sites; the attack rate in untreated stands was roughly three times that of treated stands in both California and Idaho, even at this low application rate. Furthermore, attack rate in 2004 was a significant explanatory variable for the response in 2005 regardless of treatment in both California and Idaho. There was no significant treatment effect at either site on attraction of Temnochila chlorodia (Coleoptera: Trogositidae) Mannerheim, a key predator of D. ponderosae, to the prey aggregation pheromone.

We tested methylcyclohexenone (MCH), an anti-aggregation pheromone for the Douglas-fir beetle (Dendroctonus pseudotsugae), for protection of Douglas-fir (Pseudotsuga menziesii) stands by applying MCH-releasing polymer flakes by helicopter twice during summer 2006 to five 4.05-ha plots in the State of Washington, USA. Five similar plots served as untreated controls. We assessed D. pseudotsugae flight into study plots using baited pheromone traps, and tallied D. pseudotsugae attack rates on all P. menziesii trees in 2005 and 2006. We also measured stand basal area and incorporated that as an explanatory variable in the analysis. Significantly fewer D. pseudotsugae were trapped in treated plots than in control plots, and significantly fewer P. menziesii trees were attacked in treated plots than in control plots. The attack rate in untreated stands was nearly 10 times that of treated plots, and stands with higher basal area were significantly more likely to be attacked by D. pseudotsugae than were stands of lower basal area. Attack rates in 2006 and 2005 were significantly correlated, regardless of treatment.

The western pine beetle Dendroctonus brevicomis LeConte (Coleoptera: Scolytidae) is one of the most damaging insect pests of ponderosa pines Pinus ponder osa Douglas ex P. & C. Lawson in Western U.S.A. We compared the effect of verbenone, a well known bark beetle anti-aggregation pheromone, with that of acetophenone on the attraction of D. brevicomis to its aggregation pheromone in a ponderosa pine forest in northern California. We tested the D. brevicomis ag- gregation pheromone alone and with three different release ratios of the aggregation pheromone (attractant) to verbenone or acetophenone (1 : 1, 1 : 2 and 1 : 5). 2 All treatments containing acetophenone or verbenone resulted in a significant re- duction in the catch of D. brevicomis relative to the aggregation pheromone alone. When beetle responses to the three verbenone or three acetophenone treatments were pooled, the pooled verbenone treatment caught more D. brevicomis than the pooled acetophenone treatment. 3 There was no significant difference in the number of D. brevicomis caught among the three release rates of verbenone. By contrast, the 1 : 2 attractant : acetophenone ratio attracted significantly more D. brevicomis than the traps with the 1 : 5 attractant : acetophenone ratio. 4 Attraction of a major predator, Temnochila chlorodia (Mannerheim) (Coleoptera: Trogositidae), to the aggregation pheromone of D. brevicomis was reduced by verbenone, but not by acetophenone. Moreover, the T. chlorodia : D. brevicomis ratio for the pooled acetophenone treatment was 1.7-fold greater than that for the attractant alone and two-fold greater than the ratio for the pooled verbenone treatment, suggesting that acetophenone would not disrupt populations of this natural enemy. The importance of anti-attractants in the biology of D. brevicomis and other bark beetles is discussed.

We assessed spider (Arachnida: Araneae) responses to prescribed fire following stand structure treatments in pon- derosa pine (Pinus ponderosa Dougl. ex P. & C. Laws.) stands in the Cascade Range of California. Stands were logged or left untreated to create three levels of structural diversity. We logged one treatment to minimize old-growth characteristics (low diversity) and one to enhance old-growth characteristics (high diversity) and we used unlogged Research Natural Areas (RNAs) as old-growth, highest-diversity reference stands. We conducted low-intensity prescribed fire on half of each plot fol- lowing harvest. Spider assemblages in unburned, logged stands were similar to one another but diverged from those in RNAs, with increased abundance, species richness, and diversity in more structurally diverse stands. Prescribed fire, which altered habitat in the organic soil layer where many spiders forage, resulted in altered spider assemblages and population declines in most plots. Fire generally reduced spider species richness, evenness, and diversity. Several taxa were potential indicators of fire and old-growth structure, and we discovered one species and one genus that were previously unknown. There was evi- dence that old-growth characteristics intensified the effects of fire on spider abundance. This outcome probably results from the deep litter layers in high-diversity stands and RNAs, which constituted greater fuel loads than low-diversity stands. Resume´ : Nous avons evaluela reaction des araignees (Arachnida : Araneae) au brulage dirigeala suite de traitements vi- sant amodifier la structure du peuplement dans des peuplements de pin ponderosa (Pinus ponderosa Dougl. ex P. & C. Laws.) situes dans la chaoˆne des Cascades en Californie. Les peuplements furent recoltes ou ne furent pas traites afin de creer trois niveaux de diversitestructurale. Un traitement visait a reduire au minimum les caracteristiques de vieille foret (fa- ible diversite ´), un autre visait a accentuer les caracteristiques de vieille foret (forte diversite ´) et des zones naturelles de re- cherche non exploitees qui ont eteutilisees comme peuplements temoins de vieille foret avaient la plus forte diversite ´. Nous avons effectueun brulage dirigede faible intensitedans la moitiede chacune des parcelles apresl a recolte. Les assemblages d'araignees dans les peuplements recoltes non brulesetaient semblables mais differaient de ceux des peuplements temoins. L'abondance ainsi que la richesse et la diversiteen especes etaient plus grandes dans les peuplements avec la plus forte diversitestructurale. Le brulage dirige ´, qui a alterel'habitat dans l'horizon organique du sol ouplusieurs araignees se nour- rissent, a modifieles assemblages d'araignees dont la population a diminuedans la plupart des parcelles. Le feu a generale- ment reduit la richesse, l'equitabiliteet la diversitedes especes. Plusieurs taxons etaient des indicateurs potentiels du feu et d'une structure de vieille foret et nous avons decouvert une espece et un genre jusqu'amaintenant inconnus. Il y avait des indices que les caracteristiques de vieille foret accentuent les effets du feu sur l'abondance des araignees. Ceci est probable- ment le resultat de l'epaisse couche de litiere qui constitue une charge de combustibles plus importante dans les peuplements avec une forte diversiteet les peuplements temoins que dans les peuplements avec une faible diversite ´. (Traduit par la Redaction)

We studied responses of Acari, especially oribatid mites, to prescribed low-intensity fire in an east side pine site in the southern Cascade Range in California. We compared oribatid population and assemblage responses to prescribed fire in stands that had been selectively logged to enhance old growth characteristics, in logged stands to minimize old growth characteristics, and in undisturbed forest reference stands. Low-intensity prescribed fire altered habitat characteris- tics within the organic layer of forest soil. Acarine populations declined following prescribed fire, and oribatid losses ac- counted for two thirds of that decline. Individual oribatid species responded differently to prescribed fire, with a few populations increasing after fire but most declining. The prescribed fire also altered oribatid assemblages, reducing species richness and species diversity and modifying assemblage dominance relationships. We also identified several oribatid taxa that were potential indicator species of fire effects upon forest soil fauna. Finally, our results suggested that oribatid re- sponses to fire were intensified by stand alteration and especially by removal of old growth structural characteristics. De- cline in oribatid abundance, species richness and diversity, and loss of equilibrium dominance relationships was greatest in the low structural diversity plots. Resume´ : Nous avons etudieles reponses des acariens, en particulier celles des oribates, au brulage dirigeafaible inten- sitedans une pinede exposeeal'est et situee dans la partie sud de la chaoˆne des Cascades en Californie. Nous avons com- pareles reponses des populations et des assemblages d'oribates au brulage dirigedans des peuplements qui avaient fait l'objet d'une coupe selective visant a ameliorer les caracteristiques de vieille foret, dans des peuplements coupes de man- iere a minimiser les caracteristiques de vieille foret et dans des peuplements temoins en foret non perturbee. Le brulage di- rigeafaible intensitea altereles caracteristiques d'habitat dans la couche de matiere organique du sol forestier. Les populations d'acariens ont diminueala suite du brulage dirige ´, en particulier celles des oribates dont les pertes represen- taient les deux tiers de cette diminution. Chaque espece d'oribates a reagi differemment au brulage dirige ´ : certaines popu- lations ont augmenteapres feu mais la majorited'entre elles ont diminue ´. Le brulage dirigea aussi altereles assemblages d'oribates en reduisant la richesse et la diversitespecifiques et en modifiant les relations de dominance entre les assemb- lages. Nous avons aussi identifieplusieurs taxons d'oribates qui pourraient servir d'especes indicatrices des effets du feu sur la faune du sol forestier. Finalement, nos resultats indiquent que la reponse des oribates au feu a eteamplifiee par l'al- teration du peuplement, en particulier l'elimination des caracteristiques structurales de vieille foret. Le declin de l'abondance, de la richesse et de la diversitespecifiques des oribates, ainsi que la disparition de l'equilibre des relations de dominance, etaient maximales dans les places-echantillons oula diversitestructurale etait faible. (Traduit par la Redaction)

In a study site in interior northern California, twenty individual lodgepole pines Pinus contorta were sprayed with a suspension of DISRUPT Micro-Flake ® Verbenone (4,6,6-trimethylbicyclo(3.1)hept-3-en-2-one) Bark Beetle Anti- Aggregant flakes (Hercon Environmental, Emigsville, Pennsylvania) in water, with sticker and thickener, from ground level to a height of 7 m. Twenty trees sprayed with just water, sticker and thickener served as controls. All trees were baited immediately after spraying with mountain pine beetle Dendroctonus ponde- rosae aggregation pheromone lures, and lures were refreshed after 4 weeks. 2 Trees treated with verbenone had significantly lower attack density by D. ponde- rosae than controls at 2, 4, 6 and 8 weeks after application of flakes. 3 None of the treated trees was attacked by red turpentine beetle Dendroctonus valens , whereas control trees averaged nearly two D. valens attacks per tree, 8 weeks after treatment. 4 A dry frass index, used to predict ultimate tree mortality, was significantly higher in control trees than treated trees for all four sampling intervals. This index proved to be a significant predictor of ultimate tree mortality. 5 Ten months after application, treated trees showed significantly lower mortality than control trees.

Two aerial applications of microencapsulated pheromone were conducted on five 20.2 ha plots to disrupt western pine shoot borer (Eucosma sonomana Kearfott) and ponderosa pine tip moth (Rhyacionia zozana (Kearfott); Lepidoptera: Tortricidae) orientation to pheromones and oviposition in ponderosa pine plantations in 2002 and 2004. The first application was made at 29.6 g active ingredient (AI)/ha, and the second at 59.3 g AI/ha. Baited sentinel traps were used to assess disruption of orientation by both moth species toward pheromones, and E. sonomana infestation levels were tallied from 2001 to 2004. Treatments disrupted orientation by both species for several weeks, with the first lasting 35 days and the second for 75 days. Both applications reduced infestation by E. sonomana, but the lower application rate provided greater absolute reduction, perhaps because prior infestation levels were higher in 2002 than in 2004. Infestations in treated plots were reduced by two-thirds in both years, suggesting that while increasing the application rate may prolong disruption, it may not provide greater proportional efficacy in terms of tree protection. The incidence of infestations even in plots with complete disruption suggests that treatments missed some early emerging females or that mated females immigrated into treated plots; thus operational testing should be timed earlier in the season and should comprise much larger plots. In both years, moths emerged earlier than reported previously, indicating that disruption programs should account for warmer climates in timing of applications. The AIs we tested are behaviorally active for 13 other species of Rhyacionia and six other species of Eucosma, so the approach may have wide application.

Sudden oak death (SOD), caused by Phytophthora ramorum, is killing oaks and tanoaks in the Coast Ranges of California, from Monterey County to Humboldt County. In March 2000, 20 disease progression plots were established in Marin County, California, to characterize the progress of disease symptoms, and to determine the fidelity of the association of three or more bark and ambrosia beetle species (Coleoptera: Scolytidae) with diseased oaks and tanoaks. Symptoms of sudden oak death and signs of associated organisms were recorded from coast live oaks (Quercus agrifolia), California black oaks (Q. kelloggii), valley oaks (Q. lobata), and tanoaks (Lithocarpus densiflorus), four times per year, from March 2000 through March 2003. Symptoms and signs in Q. agrifolia progressed from bleeding, to infestation by scolytid beetles, to the development of fruiting structures of the fungus Hypoxylon thouarsianum. Mortality of symptomatic trees increased from 2000 to 2003 as follows: Q. agrifolia (n = 668), 5.8‐17.4%; Q. kelloggii (n = 53), 3.8‐9.4%; and L. densiflorus (n = 164), 8.3‐22.2%. All 31 Q. lobata remained asymptomatic. From 2000 to 2003, bleeding trees were 25.0‐23.6% of living Q. agrifolia, 15.5‐25.0% of Q. kelloggii, and 39.0‐62.4% of L. densiflorus. Scolytid beetles colonized more than 95% of the living symptomatic Q. agrifolia that subsequently died. Same-symptom cohorts were followed from March 2000 through March 2003. In the asymptomatic Q. agrifolia cohort, 12.0% developed bleeding by 2003. For the bleeding only cohort, 22.7% of Q. agrifolia died, but 73.5% of the beetle-colonized bleeding cohort died. Bleeding developed in 40.9% of the initially asymptomatic L. densiflorus cohort. By 2003, 24.6% of the initially bleeding L. densiflorus cohort had died. Both Weibull and Cox Proportional Hazards regression were

We used data from two oak-woodland sites in California to develop guidelines for the design of bird monitoring programs using point counts. We used power analysis to determine sample size adequacy when varying the number of visits, count stations, and years for examining trends in abundance. We assumed an overdispersed Poisson distribution for count data, with overdispersion attributed to observer variability, and used Poisson regression for analysis of population trends. Overdispersion had a large, negative effect on power. The number of sampling years also had an especially large effect on power. In all cases, 10 years of sampling were insufficient to detect a decline in abundance of 30% over 10 years. Increasing the sampling period to 20 years provided adequate power for 56% of breeding species at one site. The number of count stations needed for detecting trends for a given species depended primarily on observer variability. If observer variability was high, increasing the number of years and visits was a better approach than increasing the number of stations. Increasing the number of stations was most beneficial for species with low abundance or low observer variability. When the number of stations is limited by the size of the area, we recommend multiple visits to stations. For most species, multiple visits per year (six or more) for 15–20 years were needed to detect a 30% decreasing trend in 10 years with adequate power. We suggest potentially useful focal species for monitoring, such as keystone species like the Acorn Woodpecker (Melanerpes formicivorus).Consideraciones de Diseño para Examinar las Tendencias en la Abundancia de Aves Usando Conteos Puntuales: Ejemplos con Datos de Bosques de Encino en CaliforniaResumen. Usamos datos de dos sitios ubicados en bosques de encino en California, con el fin de desarrollar una guía para diseñar programas de monitoreo usando conteos puntuales. Usamos un análisis del poder de la prueba para determinar el tamaño adecuado de la muestra al cambiar el número de visitas, el número de estaciones de conteo y los años de conteo con el fin de examinar las tendencias en la abundancia. Supusimos la distribución de Poisson para el conteo, con sobredispersión atribuida a la variabilidad del observador. La sobredispersión tuvo un efecto fuerte y negativo en el poder de la prueba. El efecto del número de años de muestreo fue especialmente grande sobre el poder. En cada caso, 10 años de muestreo fueron insuficientes para detectar una disminución de la abundancia del 30% en 10 años. Al aumentar el período de muestreo a 20 años, el análisis proporcionó un poder adecuado para 56% de las especies reproductivas en uno de los sitios. El número de estaciones de conteo requeridos para una especie dada dependió principalmente de la variabilidad del observador. Si la variabilidad del observador era alta, aumentar el número de años de observación y visitas fue una estrategia mejor que aumentar el número de estaciones. Aumentar el número de estaciones fue más benéfico para especies poco abundantes o con baja variabilidad del observador. Cuando el número de estaciones es limitado por el tamaño del área, recomendamos visitas múltiples a las estaciones. Para la mayoría de las especies se requieren visitas anuales múltiples (6 o más) durante 15–20 años para detectar una tendencia de decrecimiento a una razón del 30% en 10 años con un poder adecuado. Sugerimos especies focales potencialmente útiles para monitoreo tales como la especie clave Melanerpes formicivorus.

Monitoring is required of land managers and conservation practitioners to assess the success of management actions. ''Shortcuts'' are sought to reduce monitoring costs, most often consisting of the selection of a small number of species that are closely monitored to represent the status of many associated species and environmental correlates. Assumptions associated with such shortcuts have been challenged, yet alternative ap- proaches remain scant. We evaluated an approach that departs significantly from the ap- proach of selecting a few representative species. We explored two primary assertions: (1) that a coordinated multiple-species monitoring effort that collects presence-absence data on a broad range of species is a robust alternative to a few intensive single-species efforts, and (2) that the vertebrate species expected to be detected using this approach are numerous and diverse enough to represent all vertebrate species. We simulated monitoring the ver- tebrate species pool on an existing sample grid across the 7 million ha of public lands in the Sierra Nevada (USA) ecoregion. Based on the use of eight standard presence-absence protocols, we estimated the number of vertebrate species (excluding fish) with an adequate number of sample points within their range to detect $20% relative change in the proportion of points with detections between two points in time. We estimated that adequate detections would be obtained for 76% of the 465 vertebrate species, including 83% of all birds, 76% of all mammals, 65% of all reptiles, and 44% of all amphibians. Detection adequacy varied among life-history and ecological groups, but .50% of the species were adequately detected in every group with the exception of three groups: rare species, endemic species, and species of concern (33%, 24%, and 47% of associated species adequately detected, respectively). A multiple-species monitoring approach represents an effective and feasible alternative to the challenges of large-scale monitoring needs by targeting the most basic of population

To develop safe and effective methods to protect whitebark pines, Pinus albicaulis Engelmann, and limber pines, Pinus flexilis James, from attack by mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae), we compared verbenone and verbenone plus green leaf volatiles (GLVs) for prevention of beetle attack. We used two strategies: area-wide protection where semiochemical-releasing flakes are dispersed over the forest floor, and individual tree tests where flakes are applied to tree trunks. The area-wide bioassays were conducted by applying verbenone- and GLV-releasing flakes without stickers to the forest floor on 0.81-ha plots dominated by whitebark pines in the State of Washington with four replicates. We conducted individual tree bioassays by applying the same formulations with stickers to whitebark and limber pines in Montana and Colorado, respectively. In all three situations, both verbenone-alone and verbenone plus GLVs significantly increased the proportion of trees escaping mass attack by beetles, but the two formulations were not significantly different from one another. Despite a lack of significance at a Bonferroni-adjusted α = 0.05, adding GLVs gave slightly greater absolute levels of tree protection in most cases. Monitoring traps placed in the area-wide treatments in Washington showed similar outcomes for numbers of beetles trapped: both treatments had significantly fewer beetles than controls, and they were not significantly different from one another. At peak flight, however, plots with GLVs combined with verbenone had roughly 40% fewer beetles than plots with verbenone alone. GLVs are considerably cheaper than verbenone, so tests of higher application rates may be warranted to achieve enhanced tree protection at reasonable cost.

In an attempt to improve semiochemical-based treatments for protecting forest stands from bark beetle attack, we compared push-pull versus push-only tactics for protecting lodgepole pine (Pinus contorta Douglas ex Loudon) and whitebark pine (Pinus albicaulis Engelm.) stands from attack by mountain pine beetle (Dendroctonus ponderosae Hopkins) in two studies. The first was conducted on replicated 4.04-ha plots in lodgepole pine stands (California, 2008) and the second on 0.81-ha plots in whitebark pine stands (Washington, 2010). In both studies, D. ponderosae population levels were moderate to severe. The treatments were 1) push-only (D. ponderosae antiaggregant semiochemicals alone); 2) push-pull (D. ponderosae antiaggregants plus perimeter traps placed at regular intervals, baited with four-component D. ponderosae aggregation pheromone); and 3) untreated controls. We installed monitoring traps baited with two-component D. ponderosae lures inside each plot to assess effect of treatments on beetle flight. In California, fewer beetles were collected in push-pull treated plots than in control plots, but push-only did not have a significant effect on trap catch. Both treatments significantly reduced the rate of mass and strip attacks by D. ponderosae, but the difference in attack rates between push-pull and push-only was not significant. In Washington, both push-pull and push-only treatments significantly reduced numbers of beetles caught in traps. Differences between attack rates in treated and control plots in Washington were not significant, but the push-only treatment reduced attack rates by 30% compared with both the control and push-pull treatment. We conclude that, at these spatial scales and beetle densities, push-only may be preferable for mitigating D. ponderosae attack because it is much less expensive, simpler, and adding trap-out does not appear to improve efficacy.

An experiment was started in 1938 to compare methods of harvest cutting in the eastside pine type of northeastern California. The study was designed as a randomized block experiment that included 10 blocks with four to six plots per block. Each plot on which a single treatment was applied is 20 ac. Treatments removed approximately 16, 54, 74, and 95% of the original volume. One uncut control plot was established in each block. The plots were remeasured 5, 10, and 20 yr after establishment and again in 1990-1991. During the last 30 yr growth period, net growth of the sawtimber component increased with the intensity of cut and ranged from -6 ft³/ac/yr in the controls to 28 ft³/ac/yr in the 95% removal plots. Net yield during the 50 yr period was highest in the 74% removal plots and averaged 5351 ft³/ac. The number of stems in the small diameter classes has increased four to five times in all treatment plots. We theorize that this influx of small trees has increased the competitive stress and resulting mortality of the old-growth trees. West. J. Appl. For. 10(3):101-108.

White fir, Abies concolor (Gordon & Glendinning) Lindley ex Hildebrand, is an important tree species along the western slope of the Sierra Nevada in California. In 1989 and 1990, the ability of implanted applications of acephate, dimethoate, and carbofuran to protect potential scionwood from damage by the Douglas-fir tussock moth, Orgyia pseudotsugata (McDunnough), was evaluated. Dimethoate was not effective during either the first or the second year, carbofuran was effective only during the second year, and acephate was effective for two successive years after implantation. One application of acephate increased the availability of usable scions from 1 to 99% during the first year of treatment with similar results the year after treatment application.

The mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae, Scolytinae), is the most destructive bark beetle in western North America. Dendroctonus ponderosae can be prevented from successfully colonizing and killing individual trees by ground-based sprays of insecticides applied directly to the tree bole. However, the future availability of several active ingredients, including carbaryl which is most commonly used in the western United States, is uncertain. Two novel insecticides, cyantraniliprole [Cyazypyr(™)-OD (oil dispersion) and Cyazypyr(™)-SC (suspension concentrate)] and chlorantraniliprole (Rynaxypyr(®)), and carbaryl were assayed in both filter paper and topical assays.Compared with 20,000 mg L(-1) carbaryl (i.e. the maximum label rate for solutions applied to conifers for protection from bark beetle attack in the western United States), cyantraniliprole OD caused similar rates of mortality in D. ponderosae adults at 400-fold weaker concentrations in both bioassays, while cyantraniliprole SC caused similar rates of mortality at 40-fold weaker concentrations. Probit analyses confirmed that D. ponderosae is most sensitive to cyantraniliprole OD, while chlorantraniliprole was effective at concentrations similar to carbaryl.These results suggest that lower concentrations of carbaryl have merit for field testing than have been previously considered. While cyantraniliprole and chlorantraniliprole have similar modes of action, cyantraniliprole OD appears to have greater promise for protecting individual trees from mortality attributed to D. ponderosae attack and should be evaluated in field studies.

Host location and colonization by bark beetles is dependent upon the relative and absolute amounts of attractant and antiattractant compounds available. Many investigations have lead to use of antiattractants for the management of these pests and have been especially focused on verbenone. However, recent studies have identified new antiattractants for several species of bark beetles. We report results of recent investigations of the response of western pine beetle, Dendroctonus brevicomis LeConte, to two recently identified antiattractants, acetophenone, and fenchyl alcohol, with verbenone as a standard of comparison, in northern California. Release of both acetophenone and verbenone resulted in significantly lower trap catches of D. brevicomis in aggregation pheromone-baited traps, while fenchyl alcohol was inactive. Acetophenone was the only antiattractant that did not reduce numbers of the most abundant predator of D. brevicomis, Temnochila chlorodia (Mannerheim), responding to the attractant pheromone of its prey. Aggregation pheromone-baited traps with acetophenone also had the highest predator/prey ratio. Our results suggest that acetophenone may be part of the intra- and interspecific interactions among sympatric species of bark beetles and may have application in their control.

Models are fit to 11 years of storm peak flows, flow volumes, and suspended sediment loads on a network of 14 stream gaging stations in the North Fork Caspar Creek, a 473ha coastal watershed bearing a second-growth forest of redwood and Douglas-fir. For the first 4 years of monitoring, the watershed was in a relatively undisturbed state, having last been logged prior to 1904, with only a county road traversing the ridgetops. Nearly half the watershed was clear-cut over a period of 3 years, and yarded primarily using uphill skyline cable systems to spur roads constructed high on the slopes. Three tributaries were maintained as controls and left undisturbed. Four years of data were collected after logging was completed. Exploratory analysis and model fitting permit characterization and quantification of the effects of watershed disturbances, watershed area, antecedent wetness, and time since disturbance on storm runoff and suspended sediment. Model interpretations provide insight into the nature of certain types of cumulative watershed effects. INTRODUCTION This paired-watershed study in the North Fork of Caspar Creek was motivated by a desire to understand how a particular logging system affects storm peak flows, flow volumes, and suspended sediment loads in a second-growth coastal redwood forest. The logging system consisted of clear-cutting with streamside buffers, and yarding primarily by skyline to spur roads located on upper slopes and ridges. Primary objectives were to quantify how impacts vary with different levels of disturbance and how the effects of a given disturbance vary downstream. Pursuant to these objectives, a statistical model was developed for a treatment-and-control experimental design involving multiple watersheds. The study was also an opportunity for testing new technologies, and demonstrates two new automated schemes for suspended sediment sampling. Techniques for estimating sediment loads from these samples are tested and applied. Storm Peaks Throughout much of the Pacific Northwest, a large soil moisture deficit develops during the dry summer. With the onset of the rainy season in the fall, the dry soil profile begins to be recharged with moisture. In the H.J. Andrews Experimental Forest in the Oregon Cascades, the first storms of the fall produced streamflow peaks from a 96-ha clear-cut watershed that ranged from 40% to 200% larger than those predicted from the pre-logging relationship [Rothacher, 1971; 1973]. In the Alsea watershed near the Oregon coast, Harris [1977] found no significant change in the mean peak flow after clear-cutting a 71-ha watershed or patch cutting 25% of an adjacent 303-ha watershed. However, when Harr [1976] added an additional 30 smaller early winter runoff events to the data, average fall peak flow was increased 122%. In Caspar Creek, Ziemer [1981] reported that selection cutting and tractor yarding of an 85-year-old second-growth redwood and Douglas-fir forest increased the first streamflow peaks in the fall about

In a pollen exclusion experiment performed on the cones of five Douglas-fir ( Pseudotsuga menziesii [Mirbel] Franco) trees, the number of seeds infested by a seed chalcid, Megastigmus spermotrophus Wachtl, did not differ significantly between pollinated and unpollinated cones from the same tree. This finding led to a revision of the formula used to calculate M. spermotrophus effect on Douglas-fir seed production because the traditional formula, which is based on the assumption that only pollinated seeds are infested by these chalcids, exaggerates their effect. The relationship between the new formula and the traditional formula is nonlinear, varying with both pollination rate and infestation level. To assist other researchers in estimating the error in past chalcid studies, the discrepancies for a range of pollination rates were calculated. Past assessments were strongly biased only where pollination rates were