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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)

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.