Ryan P. Hanavan

Considering species richness and rarity when selecting optimal survey traps: comparisons of semiochemical baited flight intercept traps for Cerambycidae in eastern North America

We compared standard multiple‐funnel, modified multiple‐funnel, intercept panel and canopy malaise (SLAM) traps with top and bottom collecting cups for their effectiveness (species richness, rarity, abundance) at capturing Cerambycidae in eastern North America. Experiments were conducted in New York, Louisiana, Massachusetts and Georgia in 2011 and 2012. A combination of pheromones and host volatiles chosen to match local forest types were used as lures. Species richness tended to be higher in SLAM and modified funnel traps than standard funnel and intercept panel traps. SLAM traps also captured the highest number of species, unique species, rare (species accounting for ≤ 1% of total cerambycids at a site) and singleton species at each site. Individual‐based rarefaction and sample‐based species accumulation curves suggested that SLAM traps are more effective for capturing cerambycid species. For many estimates, modified funnel and funnel traps were lower than SLAM traps but greater than intercept panel traps for describing cerambycid communities. Modified funnel and SLAM traps generally captured the highest abundance of cerambycids but the response of the individual subfamily and species varied by trap type. SLAM traps should be considered as a strong tool to describe cerambycid communities when used in conjunction with pheromones and host volatiles.

Considering species richness and rarity when selecting optimal survey traps: comparison of semiochecmial baited flight intercept traps for Cerambycidae in eastern North America

We compared standard multiple‐funnel, modified multiple‐funnel, intercept panel and canopy malaise (SLAM) traps with top and bottom collecting cups for their effectiveness (species richness, rarity, abundance) at capturing Cerambycidae in eastern North America. Experiments were conducted in New York, Louisiana, Massachusetts and Georgia in 2011 and 2012. A combination of pheromones and host volatiles chosen to match local forest types were used as lures. Species richness tended to be higher in SLAM and modified funnel traps than standard funnel and intercept panel traps. SLAM traps also captured the highest number of species, unique species, rare (species accounting for ≤ 1% of total cerambycids at a site) and singleton species at each site. Individual‐based rarefaction and sample‐based species accumulation curves suggested that SLAM traps are more effective for capturing cerambycid species. For many estimates, modified funnel and funnel traps were lower than SLAM traps but greater than intercept panel traps for describing cerambycid communities. Modified funnel and SLAM traps generally captured the highest abundance of cerambycids but the response of the individual subfamily and species varied by trap type. SLAM traps should be considered as a strong tool to describe cerambycid communities when used in conjunction with pheromones and host volatiles.

Early-Season Aerial Adult Colonization and Ground Activity of Pea Leaf Weevil (Coleoptera: Curculionidae) in Pea as Influenced by Tillage System

Abstract The pea leaf weevil, Sitona lineatus (L.) (Coleoptera: Curculionidae), is an important pest of pea, Pisum sativum L., in northern Idaho. Previous research revealed greater relative pea leaf weevil abundance and feeding damage in peas grown using conventional-tillage compared with no-tillage practices. However, the effects of tillage practices on early season colonization and activity by the pea leaf weevil on pea are not fully understood. Aerial traps and pitfall traps were used to assess adult colonization and relative density of adult pea leaf weevil into conventional-tillage and no-tillage pea in northern Idaho during 2005 and 2006. Feeding damage to the crop also was evaluated. During both years, aerial traps captured more pea leaf weevil in May, when crop establishment and early growth occurred, than in later months. Significantly more adult pea leaf weevils were captured in aerial traps in conventional-tillage than in no-tillage plots in May of both years. Significantly more pea leaf weevil were captured in pitfall traps in conventional-tillage plots than in no-tillage plots during the period immediately after peak aerial adult colonization in late May and early June. Crop feeding damage was significantly greater in conventional-tillage than in no-tillage plots in late May and early June. The patterns suggest that more adult pea leaf weevil colonize conventional-tillage pea than no-tillage pea. Pea plants in conventional-tillage emerged earlier and were larger than those in no-tillage during the pea leaf weevil colonization period, possibly accounting for the differences in colonization rates. This leads to greater early season pea leaf weevil infestation of conventional-tillage plots at a critical period for pea development that might ultimately influence crop yield.

Influence of Tillage on Adult and Immature Pea Leaf Weevil (Coleoptera: Curculionidae) Densities in Pea

ABSTRACT The pea leaf weevil, Sitona lineatus (L.) (Coleoptera: Curculionidae), has been a major pest of pea, Pisum sativum L., in eastern Washington and northern Idaho since its introduction to the region in the early 1970s. Eggs are deposited in the spring on the soil surface and first instars hatch and move to pea root nodules, where larvae feed before they pupate and adults emerge in mid- to late summer. No-tillage practices are known to reduce pea leaf weevil colonization in pea, but the effects of tillage on larval densities and subsequent adult emergence have not been examined. During 2005, 2006, and 2007, we compared densities of colonizing adult and immature pea leaf weevils on pea plots grown using conventional tillage and no-tillage. In 2005 and 2006, emergence of adult pea leaf weevil was monitored in the same plots. Densities of colonizing adult and immature pea leaf weevil were significantly higher in conventional tillage plots. Larvae in conventional tillage were further along in development than larvae in no-tillage plots during June and July. Densities of emerging adult pea leaf weevil were significantly greater from conventional tillage than no-tillage plots. Based on densities of colonizing and subsequent emerging adults, survival of weevils from egg through adult was greater in conventional tillage plots, Soils under no-tillage are cooler, resulting in later emergence of the pea crop and delayed root nodule development, possibly affecting the ability of first-instar pea leaf weevil to locate host plant roots. Our results indicate no-tillage fields are less suitable for pea leaf weevil colonization and survival than conventional tillage fields.

A 10-Year Assessment of Hemlock Decline in the Catskill Mountain Region of New York State Using Hyperspectral Remote Sensing Techniques.

ABSTRACT The hemlock woolly adelgid is a serious pest of Eastern and Carolina hemlock in the eastern United States. Successfully managing the hemlock resource in the region depends on careful monitoring of the spread of this invasive pest and the targeted application of management options such as biological control, chemical, or silvicultural treatments. To inform these management activities and test the applicability of a landscape-scale remote sensing effort to monitor hemlock condition, hyperspectral collections, and concurrent ground-truthing in 2001 and 2012 of hemlock condition were compared with field metrics spanning a 10-yr survey in the Catskills region of New York. Fine twig dieback significantly increased from 9 to 15% and live crown ratio significantly decreased from 67 to 56% in 2001 and 2012, respectively. We found a significant shift from 59% “healthy” hemlock in 2001 to only 16% in 2012. However, this shift from healthy to declining classifications was mostly a shift to decline class 2 “early decline”. These results indicate that while there has been significant increase in decline symptoms as measured in both field and remote sensing assessments, a majority of the declining areas identified in the resulting spatial coverages remain in the “early decline” category and widespread mortality has not yet occurred. While this slow decline across the region stands in contrast to many reports of mortality within 10 yr, the results from this work are in line with other long-term monitoring studies and indicate that armed with the spatial information provided here, continued management strategies can be focused on particular areas to help control the further decline of hemlock in the region.

Influence of no-tillage practices and later planting date on the pea leaf weevil, Sitona lineatus, in pea, Pisum sativum

The pea leaf weevil, Sitona lineatus (L.) (Coleoptera: Curculionidae), is a periodic pest of pea, Pisum sativum L. (Fabaceae), in the Palouse region of northern Idaho and eastern Washington, USA. Previous work on‐station and in commercial pea fields showed initial adult weevil colonization was greater in conventional‐tillage than in no‐tillage fields. Increased surface residue of no‐tillage systems results in cooler soils with greater available moisture typically resulting in later planting dates for conventional‐tillage fields. Cereal residue, a characteristic of the regions no‐tillage systems, and planting date were investigated as potential inhibitors of adult pea leaf weevil colonization and feeding on peas via field experiments in 2005 and 2006. Plots without cereal residue and early‐planted plots had greater weevil abundance. Early‐planted peas had greater weevil feeding injury compared to late‐planted peas. The presence of cereal residue did not significantly impact injury levels. A laboratory choice‐test with peas grown in conventional‐tillage and no‐tillage fields indicated greater adult weevil feeding damage on conventional‐tillage‐grown peas. A separate laboratory choice‐test using peas planted 10 days apart demonstrated greater adult weevil feeding injury on early‐planted peas. However, adjusting for available leaf edge resulted in no differences between treatments in either choice test, indicating crop availability and plant apparency during peak weevil colonization rather than plant factors resulting from growing conditions likely explain greater injury on peas planted early and under conventional‐tillage in the field.

Firewood collected after a catastrophic wind event: the bark beetle (Scolytinae) and woodborer (Buprestidae, Cerambycidae) community present over a 3‐year period

An EF 3 tornado created a 63‐km path through urban and forested areas of western Massachusetts, U.S.A., on 1 June 2011. We collected ash, birch, maple, oak and pine logs from the tornado blowdown, once per year, over a 3‐year period and split these into firewood sized pieces. Firewood was then placed into rearing barrels and insects were collected for 1 year. An estimated 38 121 beetles from 42 species of Buprestidae, Cerambycidae and Curculionidae: Scolytinae were reared from firewood over the 3‐year period. The most abundant species collected included Hylesinus aculeatus Say (85% of total), Xyleborinus attenuatus (Blandford) (3.9%) and Monarthrum mali (Fitch) (3.6%). The largest abundance of insects was found from ash in 2012 and 2014, and from maple in 2013. Species richness was highest in oak in 2012 and 2013, and in birch and pine in 2014. Four species of exotic xyleborines [Cyclorhipidion pelliculosum (Eichhoff), X. attenuatus, Xyleborinus saxesenii and Xylosandrus germanus (Bladford)] were reared out of every firewood genus and accounted for a large proportion of the Scolytinae captured. Potential new host associations include the Cerambycidae Astylopsis macula (Say) in red pine, the Scolytinae Gnathotrichus materiarius (Fitch) in hardwoods, and M. mali, X. attenuatus and X. saxesenii in ash. Firewood harvested from a large scale disturbance in northeastern hardwood forests produced large numbers of insects, even 3 years after the disturbance.

Effects of tillage practices on pea leaf weevil (Sitona lineatus L., Coleoptera: Curculionidae) biology and crop damage: a farm-scale study in the US Pacific Northwest.

The pea leaf weevil, Sitona lineatus L., is periodically a significant pest of pea, Pisum sativum L., in the Palouse region of northern Idaho and eastern Washington, USA. Previous on-station research demonstrated significantly greater adult pea leaf weevil colonization, immature survival, adult emergence and plant damage in conventional-tillage compared to no-tillage plots of pea. In experiments conducted during the 2006 and 2007 growing seasons, aerial and ground adult pea leaf weevil colonization of large-scale commercial pea fields under different tillage regimes in northern Idaho and eastern Washington was examined for the first time. Initial pea leaf weevil feeding damage, immature weevil densities and subsequent adult emergence from the fields were also assessed. During both years, significantly more adult pea leaf weevils were captured in conventional-tillage than in no-tillage fields during the crop establishment period in May. No-tillage soils remained wet longer in the spring and could not be planted by growers until later than conventional-tillage fields. Pea planted under conventional-tillage emerged earlier and had significantly greater feeding damage by the pea leaf weevil than no-tillage pea. Significantly, greater immature pea leaf weevil densities and subsequent adult emergence were observed in conventional-tillage than in no-tillage pea fields. Delayed development of root nodules in the cooler, moister conditions of no-tillage pea fields likely resulted in escape from attack and injury during the critical growth stages that ultimately influence yield. Results indicate that large-scale commercial no-tillage pea fields are less suitable for colonization and survival of the pea leaf weevil and suffer less weevil damage than fields under conventional tillage.