Daniel R. Miller

Effects of post-wildfire erosion on channel environments, Boise River, Idaho

What is the geological or ecological context that earth scientists, biologists, and resource managers use to understand largescale watershed disturbances, such as fires, mass wasting, and floods? We address this question using a field study of post-fire channel changes in the Boise River basin in central Idaho based on surveys of over 27 km of channels. Intense rill and gully erosion from the Rabbit Creek fire (1995) greatly increased sediment supply to numerous third- through sixth-order valley floors. We concentrated our field study where recently aggraded and enlarged alluvial fans impinged on channels in drainage areas of 100‐350 km 2 . Alluvial fans that had enlarged because of post-fire sedimentation triggered a number of morphological changes in channels and valley floors. Alluvial fans created nick points in receiving channels that caused an increase in channel gradient immediately downstream of fans and a decrease in channel gradients upstream of fans for distances up to 4 km. Wide floodplains, side channels, and the beginning of terrace construction were associated with increased sediment storage in proximity to aggraded fans. Fan-related changes in channel gradients also affected the spatial distribution of channel substrates. Studies across western North America indicate that periodic, large influxes of sediment to channels are a fundamental part of stream ecosystems. In addition, new perspectives in riverine ecology focus on the patchy distribution of aquatic habitats. Our study integrates those two perspectives by illustrating how fire-related sediment production coupled with irregularly spaced tributary junctions contributed to the formation of certain types of riverine habitats. # 2003 Elsevier Science B.V. All rights reserved.

Time, space, and episodicity of physical disturbance in streams

Storm-driven episodes of gully erosion and landsliding produce large influxes of sediment to stream channels that have both immediate, often detrimental, impacts on aquatic communities and long-term consequences that are essential in the creation and maintenance of certain channel and riparian landforms. Together, these effects form an important component of river ecosystems. In this paper, we describe issues involved in characterizing and predicting the frequency, magnitude, spatial extent, and synchrony of these sediment influxes. The processes that drive sediment fluxes exhibit spatial and temporal variability over a large range of scales. Disregard of this variability can have unanticipated consequences for efforts to quantify process rates, as we illustrate using landslide densities observed for a storm event in western Oregon. Multiple factors interact to create the temporal and spatial patterns of erosional and mass-wasting events that affect stream channels. Fires, in particular, enhance susceptibility to erosional and mass-wasting processes, and thus affect the timing and magnitude of sediment-mobilizing events. We use examples from west-central Idaho to show how fires, storms, and topography interact to create spatially distinct patches of intense erosional activity. We require quantitative descriptions of these controlling factors to make quantitative predictions of how differences or changes in topography, fire regime, and climate will affect the regime of sediment fluxes. The stochastic and heterogeneous nature of these factors leads us to quantify them in probabilistic terms. The effects of future fire and storm sequences are governed in part by the past sequence of events over time frames spanning centuries and spatial extents spanning entire river basins. Empirical characterization of past events poses a considerable challenge, given that our observational record typically spans several decades at most. Numerical models that simulate multiple event sequences provide an alternative means for estimating the influence of antecedent conditions and for quantifying the role of different controlling factors.

Inter- and intrapopulation variation of the pheromone, ipsdienol produced by male pine engravers,Ips pini (Say) (Coleoptera: Scolytidae)

We determined the chirality of ipsdienol in individual male pine engravers,Ips pini (Say), from New York, California, and two localities in British Columbia (BC). Both quantity and chirality of ipsdienol varied significantly between and within populations ofI. pini. Beetles from California and southeastern BC produced primarily (R)-(−)-ipsdienol with mean ratios of (S)-(+) : (R)-(−) of 9 : 91 and 11 : 89, respectively, while beetles from New York produced primarily (S)-(+)-ipsdienol with a mean (S)-(+) : (R)-(−) ratio of 57 : 43. A population from southwestern BC was unlike any other known western population, producing primarily (S)-(+)-ipsdienol with a mean (S)-(+) : (R)-(−) ratio of 66 : 34. In contrast to the unimodal chirality profiles for ipsdienol production in populations from California and southeastern BC, the profiles of the populations from southwestern BC and New York were bimodal, with a common mode at approximately 44 : 56 (S)-(+) : (R)-(−). Bimodality in the profiles of ipsdienol chirality in two populations ofI. pini and remarkably high levels of intrapopulation variation in pheromone chirality in all four populations suggest that evolutionary change in pheromone channels of communication could occur, possibly in response to artificial selection pressures such as mass trapping.

Effect of verbenone on five species of bark beetles (Coleoptera: Scolytidae) in Lodgepole pine forests

Abstract The response by five species of bark beetles to a range of verbenone doses were tested in bioassays using Lindgren funnel traps baited with attractant semiochemicals. The objective was to determine how these bark beetles respond to verbenone, a purported anti-aggregation pheromone of several economically significant bark beetle species. Catches of Dendroctonus ponderosae Hopkins, a species attacking live trees, were unaffected relative to a control trap (no verbenone) at release rates of 0.2 mg/24 h or less, but were significantly reduced at rates of 1.8 mg/24 h or more. Catches of Ips pini (Say) and I. latidens (LeConte), two opportunistic species normally attacking fresh, dead host material, were gradually reduced with increasing verbenone dose. Verbenone did not affect catches of Hylurgops porosus (LeConte) and Hylastes longicollis Swaine, two species normally associated with bark in contact with the ground, where saprophytic microorganisms quickly invade phloem tissue. The effect by verbenone on catches of the five species was consistent with differences in host-age preference. Catches of species requiring relatively fresh host tissue were reduced by verbenone, whereas catches of species accepting aged tissue were unaffected.

Bark beetle pheromones and pine volatiles: attractant kairomone lure blend for longhorn beetles (Cerambycidae) in pine stands of the southeastern United States.

ABSTRACT In 2006, we examined the flight responses of 43 species of longhorn beetles (Coleoptera: Cerambycidae) to multiple-funnel traps baited with binary lure blends of 1) ipsenol + ipsdienol, 2) ethanol + &agr;-pinene, and a quaternary lure blend of 3) ipsenol + ipsdienol + ethanol + &agr;-pinene in the southeastern United States. In addition, we monitored responses of Buprestidae, Elateridae, and Curculionidae commonly associated with pine longhorn beetles. Field trials were conducted in mature pine (Pinus pp.) stands in Florida, Georgia, Louisiana, and Virginia. The following species preferred traps baited with the quaternary blend over those baited with ethanol + &agr;-pinene: Acanthocinus nodosus (F.), Acanthocinus obsoletus (Olivier), Astylopsis arcuata (LeConte), Astylopsis sexguttata (Say), Monochamus scutellatus (Say), Monochamus titillator (F.) complex, Rhagium inquisitor (L.) (Cerambycidae), Buprestis consularis Gory, Buprestis lineata F. (Buprestidae), Ips avulsus (Eichhoff), Ips calligraphus (Germar), Ips grandicollis (Eichhoff), Orthotomicus caelatus (Eichhoff), and Gnathotrichus materiarus (Fitch) (Curculionidae). The addition of ipsenol and ipsdienol had no effect on catches of 17 other species of bark and wood boring beetles in traps baited with ethanol and &agr;-pinene. Ethanol + &agr;-pinene interrupted the attraction of Ips avulsus, I. grandicollis, and Pityophthorus Eichhoff spp. (but not I. calligraphus) (Curculionidae) to traps baited with ipsenol + ipsdienol. Our results support the use of traps baited with a quaternary blend of ipsenol + ipsdienol + ethanol + &agr;-pinene for common saproxylic beetles in pine forests of the southeastern United States.

Comparison of arboreal beetle catches in wet and dry collection cups with Lindgren multiple funnel traps.

Abstract We compared the effectiveness of a dry collection cup (with an insecticide killing strip) to a wet collection cup (containing antifreeze) for use with Lindgren multiple-funnel traps in catching several common species of bark and wood-boring beetles, and their associates in southern pine forests. All traps were baited with either the binary combination of ethanol and (−)-α-pinene or the quaternary combination of (±)-ipsenol, (±)-ipsdienol, ethanol, and (−)-α-pinene. We found that cup treatment had little, if any, effect on catches of Ips avulsus (Eichhoff) and I. grandicollis (Eichhoff) (Coleoptera: Scolytidae), Alaus myops (F.) (Elateridae), Chalcophora Solier species (Buprestidae), Temnochila virescens (F.) (Trogositidae), and Lasconotus Erichson species (Colydiidae). In contrast, catches of the following species were significantly less (by 40–97%) in traps with dry cups than in traps with wet cups: Hylobius pales Herbst and Pachylobius picivorus LeConte (Curculionidae); Buprestis lineata F. (Buprestidae); Acanthocinus obsoletus (Olivier), Arhopalus rusticus nubilus (LeConte), Monochamus titillator (F.) and Xylotrechus sagittatus sagittatus (Cerambycidae); Hylastes porculus Erichson and Xyleborinus saxeseni (Ratzeburg) (Scolytidae); and Thanasimus dubius (F.) (Cleridae). The same was true in at least one experiment for the following species: Dendroctonus terebrans (Olivier), Hylastes salebrosus Eichhoff, Hylastes tenuis Eichhoff, and Xylosandrus crassiusculus (Motschulsky) (Scolytidae). We conclude that cup treatment can have a significant impact on catches of some arboreal beetles in baited multiple-funnel traps. Anyone using multiple-funnel traps to capture arboreal beetles should evaluate the potential impacts arising from their choice of collection cup treatment to their trapping objectives and expectations. The issue of cup treatment may be particular important at low population levels when maximum trap efficiency is required such as in the detection of exotic insects at ports-of-entry and within quarantine and containment zones.

Ipsenol and Ipsdienol Attract Monochamus titillator (Coleoptera: Cerambycidae) and Associated Large Pine Woodborers in Southeastern United States

We determined the responses of the southern pine sawyer, Monochamus titillator (F.) (Coleoptera: Cerambycidae), to the pheromones (ipsenol, ipsdienol, and lanierone) used by pine engraver beetles (Coleoptera: Scolytidae) in the southeastern United States. (+/-)-Ipsenol, (+/-)-ipsdienol, or a combination increased catches of M. titillator in Florida, Louisiana, Georgia, and North Carolina. Catches of Acanthocinus obsoletus (Olivier) (Cerambycidae) were increased by (+/-)-ipsenol and (+/-)-ipsdienol in Florida and North Carolina, whereas only (+/-)-ipsenol was attractive in Georgia. (+/-)-Ipsenol and (+/-)-ipsdienol were attractive to Pachylobius picivorus (Germar) (Coleoptera: Curculionidae) in Florida, whereas only (+/-)-ipsdienol was active in Louisiana. In Florida, catches of M. titillator, A. obsoletus, and P. picivorus were greatest in traps baited with both (+/-)-ipsenol and (+/-)-ipsdienol. In Louisiana, catches of the woodborer Chalcophora virginiensis (Drury) (Buprestidae) were increased by (+/-)-ipsenol. Lanierone did not affect trap catches of the aforementioned species. The combination of (+/-)-ipsenol and (+/-)-ipsdienol may be a cost-effective lure for these four species because we found no evidence of interruption in attraction to baited traps, and the cost of the lure combination is relatively low.

Ipsenol: an aggregation pheromone for Ips latidens (LeConte) (Coleoptera: Scolytidae)

Ipsenol was identified from the frass of male, but not female,Ips latidens from British Columbia, feeding in phloem tissue of lodgepole pine,Pinus contorta var.latifolia. The responses ofJ. latidens to sources of ips-enol andcis-verbenol were determined with multiple-funnel traps in stands of lodgepole pine in British Columbia. Ipsenol attracted both male and femaleI. latidens, verifying that it is a pheromone for this species. MaleI. latidens showed a slight preference for (S)-(−)-ipsenol.cis-Verbenol was not produced by beetles of either sex and, in contrast to an earlier report, both enantiomers inhibited attraction to ipsenol-baited traps. The predators,Enoclerus sphegeus andThanasimus undatulus (Cleridae), were attracted to traps baited withcis-verbenol and ipsenol.

Attaching Lures to Multiple-Funnel Traps Targeting Saproxylic Beetles (Coleoptera) in Pine Stands: Inside or Outside Funnels?

ABSTRACT We conducted two field trapping experiments with multiple-funnel traps in 2008 and one experiment in 2010 to determine the effects of lure placement (inside or outside funnels) on catches of saproxylic species of beetles (Coleoptera). The experiments were conducted in southern pine (Pinus spp.) stands in central Georgia using combinations of ethanol, &agr;-pinene, ipsenol, and ipsdienol lures. We report on a modification to the multiple-funnel trap that allows placement of large lures inside the confines of the funnels with minimal blockage. In general, catches of five species of common longhorn beetles (Cerambycidae), two species of regeneration weevils (Curculionidae), four species of bark beetles (Curculionidae: Scolytinae), and seven species of beetle predators and ectoparasites (Cleridae, Histeridae, Tenebrionidae, Trogossitidae, and Zopheridae) were higher in funnel traps with lures attached inside the funnels than in those with lures attached outside of the funnels. Catches of the remaining species were unaffected by lure placement. In no instance were catches of any species lower in funnel traps with lures attached inside the funnels than in those with lures attached outside of the funnels. For most species, catches in modified funnel traps with ethanol, &agr;-pinene, ipsenol, and ipsdienol lures attached inside funnels were comparable with those in cross-vane panel traps.

Effect of Verbenone on Attraction of Predatory and Woodboring Beetles (Coleoptera) to Kairomones in Lodgepole Pine Forests

Abstract The response of bark beetle predators and woodboring beetles to the bark beetle anti-aggregation pheromone, verbenone, was tested in the field with multiple-funnel traps baited with attractant kairomones. Catches of the predators Thanasimus undatulus (Say), Enoclerus sphegeus (F.), Enoclerus lecontei (Wolcott) (Coleoptera: Cleridae), and Lasconotus complex LeConte (Coleoptera: Colydiidae) declined significantly with increasing release rates of verbenone. Lasconotus subcostulatus Kraus, and Corticeus praetermissus (Fall) (Coleoptera: Tenebrionidae) (in two of three experiments), showed no significant response to verbenone. In a third experiment, catches of C. praetermissus increased with verbenone dose. Likewise, catches of the striped ambrosia beetle, Trypodendron lineatum (Olivier) (Coleoptera: Scolytidae), increased with verbenone dose in one experiment, but there was no effect in two other experiments. Verbenone had no effect on the response of Spondylis upiformis Mannerheim (Coleoptera: Cerambycidae). We hypothesize that predators specializing on early successional bark beetles are repelled by verbenone since this compound indicates a late stage attack. Generalist predators and woodborers either do not respond to verbenone at all, or they may be attracted by it.