Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 30 of 46

Full-Text Articles in Life Sciences

Surface Waters: Ammonium Is Not Ammonia – Part 3, John E. Sawyer, Matthew J. Helmers Jul 2016

Surface Waters: Ammonium Is Not Ammonia – Part 3, John E. Sawyer, Matthew J. Helmers

John E. Sawyer

Two previous ICM News articles outlined the difference between ammonium and ammonia, the relationship between the two nitrogen forms, and the implication of a combined (ammonium-N plus ammonia-N) analysis related to water quality criteria for aquatic life and chlorination treatment for drinking water.This article focuses on the potential sourcing of ammonium and ammonia in surface waters. Ammonium and ammonia in surface water systems can originate from many sources, and are naturally occurring forms of nitrogen. Predominant sources will vary on a watershed or sub-watershed basis. Also, sources and concentrations are greatly influenced by hydrology, including timing and volume of water …


Corn Following Corn In 2008, Mahdi Al-Kaisi, Roger W. Elmore, Antonio P. Mallarino, Palle Pedersen, Alison E. Robertson, John E. Sawyer, Jon J. Tollefson Jul 2016

Corn Following Corn In 2008, Mahdi Al-Kaisi, Roger W. Elmore, Antonio P. Mallarino, Palle Pedersen, Alison E. Robertson, John E. Sawyer, Jon J. Tollefson

John E. Sawyer

Corn following corn is in rough shape in areas across Iowa. Many wonder what is happening. The crop’s condition in general is not normal for this time of year. For example, last Sunday the USDA rated this year’s Iowa corn crop as 54 percent in ‘Good’ to ‘Excellent’ condition and 15 percent is ‘Poor’ or ‘Very Poor.’ Last year 72 percent was rated ‘Good’ to ‘Excellent’ and 5 percent was in ‘Poor’ or ‘Very Poor’ condition during the same week. Average plant height as of Sunday was 24 inches compared to 40 inches at end of the same week last …


Ec86-1548 Common Insect Pests Of Trees In The Great Plains, Mary Ellen Dix, Judith E. Pasek, Mark O. Harrell, Frederick P. Baxendale Jul 2015

Ec86-1548 Common Insect Pests Of Trees In The Great Plains, Mary Ellen Dix, Judith E. Pasek, Mark O. Harrell, Frederick P. Baxendale

Judith E Pasek

This publication was developed by entomologists on the Pest Management Task Force of the Great Plains Agricultural Council Forestry Committee to provide the public and professionals with information needed to identify and manage common insect pests of trees in the Great Plains. It is designed for those with no formal training in entomology and is not intended to summarize everything known about a particular insect.


Infestation Of Aetalion Reticulatum (Linnaeus) (Hemiptera: Aethalionidae) In Plants Of Euterpe Oleracea Martius (Arecaceae) In Acre State, Brazil, Rodrigo Souza Santos Rss Jan 2015

Infestation Of Aetalion Reticulatum (Linnaeus) (Hemiptera: Aethalionidae) In Plants Of Euterpe Oleracea Martius (Arecaceae) In Acre State, Brazil, Rodrigo Souza Santos Rss

Rodrigo Souza Santos RSS

The açai palm (Euterpe oleracea Martius) is a native palm tree from the Amazon region floodplains and may be indicated as the most economically profitable species of this genus. Its fruit pulp is extracted and widely consumed by the population of northern Brazil in several ways. With the expansion of the planted area many factors may affect the production and limit the cultivation, highlighting the occurrence of insect pests that cause losses in production. This report presents the first occurrence of the leafhopper Aetalion reticulatum (Linnaeus) (Hemiptera: Auchenorrhyncha: Aethalionidae) in E. oleracea plants. The occurrence of this insect associated with …


Use Of The Internet For Information Organization, Distance Learning, And Specimen Presentation , John Kevin Vandyk Oct 2014

Use Of The Internet For Information Organization, Distance Learning, And Specimen Presentation , John Kevin Vandyk

John K. VanDyk

The advent of the internet has had an effect on the discipline of entomology. The history of the relationship between entomology and the internet is summarized, and several effects are examined in detail. One effect is to create an explosion of available information about insects and pest management, largely available on the world-wide web (WWW). A metadata-based solution to categorizing, searching and filtering this information is presented, along with a case study that used this solution to examine the value added by the use of metadata. In the case study website, one third of the users arrived at web pages …


Taming Of The Skew: Transactional Models Fail To Predict Reproductive Partitioning In The Paper Wasp Polistes Dominulus, Aviva Liebert, Philip Starks Feb 2013

Taming Of The Skew: Transactional Models Fail To Predict Reproductive Partitioning In The Paper Wasp Polistes Dominulus, Aviva Liebert, Philip Starks

Aviva E Liebert

Female Polistes paper wasps can initiate colonies either solitarily or in cooperative groups. Reproduction is often distributed unequally in groups, even to the point of complete monopolization of breeding by the dominant group member. Transactional models of reproductive skew predict the degree of reproductive partitioning, assuming that the dominant controls group membership and will yield a proportion of reproduction to a subordinate as an incentive to stay peacefully in the group. Using a combination of demographic, genetic and morphological data from a population of P. dominulus, we test predictions of 'classical' two-person skew models as well as more complex …


Sexual Interactions And Nestmate Recognition In Invasive Populations Of Polistes Dominulus Wasps, Aviva Liebert, N Wilson-Rich, C Johnson, Philip Starks Feb 2013

Sexual Interactions And Nestmate Recognition In Invasive Populations Of Polistes Dominulus Wasps, Aviva Liebert, N Wilson-Rich, C Johnson, Philip Starks

Aviva E Liebert

Many social insect species have mating systems or recognition abilities that minimize the chance of inbreeding. In haplodiploid systems, inbreeding is especially costly due to the production of sterile offspring such as diploid males. Diploid males (and their triploid offspring) have been identified in invasive populations of the paper wasp, Polistes dominulus, but to date have not been reported in its native populations. Due to the degree of genetic diversity in the invasive populations, it is unlikely that the production of these genetic ‘misfits’ is the result of a genetic bottleneck alone, but rather that errors in nestmate recognition may …


Nest Hydrocarbons As Cues For Philopatry In A Paper Wasp, Annagiri Sumana, Aviva Liebert, Anne Berry, Ghislaine Switz, Colin Orians, Philip Starks Feb 2013

Nest Hydrocarbons As Cues For Philopatry In A Paper Wasp, Annagiri Sumana, Aviva Liebert, Anne Berry, Ghislaine Switz, Colin Orians, Philip Starks

Aviva E Liebert

Philopatric behavior has been demonstrated in a wide taxonomic spread of animals. In temperate environments, overwintered Polistes wasp foundresses often return to their natal nest prior to initiating colony construction. Previous research has shown that these spring foundresses can identify the natal nest in the absence of landmark and gross morphological cues. Hydrocarbons are essential recognition cues for Polistes nest and nestmate discrimination, but cuticular hydrocarbon profiles can become homogenized when foundresses overwinter in mixed colony groups. We examined the hydrocarbon profiles of Polistes dominulus foundresses and nests before and after an overwintering period, and found that the hydrocarbon profiles …


Extreme Polygyny: Multi-Seasonal “Hypergynous” Nesting In The Introduced Paper Wasp Polistes Dominulus, Aviva Liebert, Julia Hui, Peter Nonacs, Philip Starks Feb 2013

Extreme Polygyny: Multi-Seasonal “Hypergynous” Nesting In The Introduced Paper Wasp Polistes Dominulus, Aviva Liebert, Julia Hui, Peter Nonacs, Philip Starks

Aviva E Liebert

In temperate climates, female paper wasps typically initiate new colonies in the spring. Several nest-founding tactics have been documented in Polistes species, including solitary nest initiation, joining a cooperative association, usurping an existing nest, or adopting an abandoned nest. Occasionally, exceptionally large groups of females have also been found reusing nests from the previous season. Here we report this phenomenon in introduced populations of the Eurasian species Polistes dominulus. We describe in detail the demographic and genetic characteristics of one such spring colony from Los Angeles, California, USA, which was collected with 84 associated adults and all stages of developing …


Solitary Nesting And Reproductive Success In The Paper Wasp Polistes Aurifer, Aviva Liebert, Peter Nonacs, Robert Wayne Feb 2013

Solitary Nesting And Reproductive Success In The Paper Wasp Polistes Aurifer, Aviva Liebert, Peter Nonacs, Robert Wayne

Aviva E Liebert

Female Polistes paper wasps are capable of independent nesting, yet many populations demonstrate a mixture of solitary and cooperative nest foundation. Previous studies of Polistes have found survival and/or productivity advantages of cooperative nest foundation compared to solitary nesting, and reproductive skew models have been designed to predict the dynamics of such flexible cooperation. In this paper, we examine the success of different nesting strategies in a previously unstudied population of Polistes aurifer in southern California. The colony cycle of this population is less synchronous than that of other temperate species, and the frequency of solitary nesting averages 86.2%. Our …


Diploid Males And Their Triploid Offspring In The Paper Wasp Polistes Dominulus, Aviva Liebert, Annagiri Sumana, Philip Starks Feb 2013

Diploid Males And Their Triploid Offspring In The Paper Wasp Polistes Dominulus, Aviva Liebert, Annagiri Sumana, Philip Starks

Aviva E Liebert

Although the hymenopteran sex-determining mechanism generally results in haploid males and diploid females, diploid males can be produced via homozygosity at the sex-determining locus. Diploid males have low fitness because they are effectively sterile or produce presumably sterile triploid offspring. Previously, triploid females were observed in three species of North American Polistes paper wasps, and this was interpreted as indirect evidence of diploid males. Here we report what is, to our knowledge, the first direct evidence: four of five early male-producing Polistes dominulus nests from three populations contained diploid males. Because haploid males were also found, however, the adaptive value …


Ground Nesting In The Paper Wasp Polistes Aurifer (Hymenoptera: Vespidae), Aviva Liebert Feb 2013

Ground Nesting In The Paper Wasp Polistes Aurifer (Hymenoptera: Vespidae), Aviva Liebert

Aviva E Liebert

Polistes paper wasp species vary in their nest site selection, with some nesting in relatively exposed areas and others in protected cavities. Locating the nest sites of cavity dwelling species in natural habitat can prove difficult, and most behavioral studies on these species are therefore conducted using human-built structures. Since Hungerford and Williams (1912) and Rau (1929) noted the location of several P. fuscatus (Fabricius) nests in rodent burrows, there have been no published accounts of ground nesting Polistes species. I report the occurrence of a large, dense cluster of P. aurifer (Saussure) nests located within cracks in the dried …


Transactional Skew And Assured Fitness Return Models Fail To Predict Patterns Of Cooperation In Wasps, Peter Nonacs, Aviva Liebert, Philip Starks Dec 2012

Transactional Skew And Assured Fitness Return Models Fail To Predict Patterns Of Cooperation In Wasps, Peter Nonacs, Aviva Liebert, Philip Starks

Aviva E Liebert

Cooperative breeders often exhibit reproductive skew, where dominant individuals reproduce more than subordinates. Two approaches derived from Hamilton’s inclusive fitness model predict when subordinate behavior is favored over living solitarily. The assured fitness return (AFR) model predicts that subordinates help when they are highly likely to gain immediate indirect fitness. Transactional skew models predict dominants and subordinates “agree” on a level of reproductive skew that induces subordinates to join groups. We show the AFR model to be a special case of transactional skew models that assumes no direct reproduction by subordinates. We use data from 11 populations of four wasp …


Genetics, Behavior And Ecology Of A Paper Wasp Invasion: Polistes Dominulus In North America, Aviva Liebert Dec 2012

Genetics, Behavior And Ecology Of A Paper Wasp Invasion: Polistes Dominulus In North America, Aviva Liebert

Aviva E Liebert

Studies of social insect invasions to date have focused primarily on highly eusocial insects such as ants and yellowjacket wasps. Yet insect societies without fixed, morphological caste systems may be particularly good invaders due to their behavioral flexibility, as demonstrated by the recent invasion of the European paper wasp Polistes dominulus into North America. Here we provide a review of this ongoing invasion in terms of (1) population genetic variation in P. dominulus, and (2) comparative behavior and ecology of P. dominulus vs. the native P. fuscatus. We present new genetic evidence supporting the occurrence of multiple independent introductions of …


G74-108 Wilts Of Cucurbits (Revised October 1994), James R. Steadman, David L. Keith, Laurie Hodges Sep 2012

G74-108 Wilts Of Cucurbits (Revised October 1994), James R. Steadman, David L. Keith, Laurie Hodges

Laurie Hodges

Discussion covers the symptoms, disease cycles, and control measures for bacterial and Fusarium wilts of cucurbits, including cucumbers, cantaloupe, watermelons, squash, and pumpkins. Wilt caused by squash vine borer also is covered.


G73-46 Hessian Fly On Wheat, John E. Foster, Gary L. Hein Mar 2012

G73-46 Hessian Fly On Wheat, John E. Foster, Gary L. Hein

John E. Foster

This NebGuide discusses the life cycle, control and prevention of the Hessian fly. Plant-safe dates and resistant wheat varieties are also examined. The Hessian fly, Mayetiola destructor (Say), is not native to the United States, but was probably introduced by Hessian soldiers during the Revolutionary War. This insect was given its common name by Americans because of its damage on Long Island in 1779. The pest has become distributed throughout the United States wheat production areas since then. The Hessian fly belongs to the family of insects known as gall midges (Diptera: Cecidomyiidae), a group noted for their habit of …


Desempenho Do Bicho-Da-Seda (Lepidoptera: Bombycidae) Sob O Efeito Da Adição De Minerais Nas Folhas De Amoreira Antes E Depois Do Trato Alimentar, Rodrigo Souza Santos Rss Jan 2010

Desempenho Do Bicho-Da-Seda (Lepidoptera: Bombycidae) Sob O Efeito Da Adição De Minerais Nas Folhas De Amoreira Antes E Depois Do Trato Alimentar, Rodrigo Souza Santos Rss

Rodrigo Souza Santos RSS

No abstract provided.


New Models Of Emergence Traps For Endophytic Egg Parasitoids Capture, Rodrigo Souza Santos Rss Jan 2009

New Models Of Emergence Traps For Endophytic Egg Parasitoids Capture, Rodrigo Souza Santos Rss

Rodrigo Souza Santos RSS

For strain selection studies of natural enemies from the field, studies of behavior or even of taxonomy, capture of alive insects are of great importance. One alternative for obtaining adult parasitoids (Hymenoptera) is the use of emergency traps. Therefore, the objective of this work was to propose two models of emergency traps (traps like “box” and “bottle”), for obtaining alive endophytic egg parasitoids. The two models proposed were efficient in the capture of alive parasitoids, however a larger capture of specimens was observed in the “box” trap in relation to the e “bottle”, due to larger folioles storage inside the …


Description Of New Species Of Fidicinoides Boulard & Martinelli (Hemiptera: Cicadidae) From Brazil, Rodrigo Souza Santos Rss Jan 2009

Description Of New Species Of Fidicinoides Boulard & Martinelli (Hemiptera: Cicadidae) From Brazil, Rodrigo Souza Santos Rss

Rodrigo Souza Santos RSS

The examination of entomological collections of cicadas of several Brazilian institutions revealed three undescribed species in the genus Fidicinoides Boulard & Martinelli i.e., F. dolosa sp.n., F. carmenae sp.n. and F. rosabasalae sp.n. They are described and illustrated based on the male genitalia, the right anterior femur and the operculum.


Diversity And Spatial Distribution Of Ground Arthropods In Agroecosystems, Rodrigo Souza Santos Rss Jan 2009

Diversity And Spatial Distribution Of Ground Arthropods In Agroecosystems, Rodrigo Souza Santos Rss

Rodrigo Souza Santos RSS

The knowledge of the diversity and distribution of ground arthropods contributes for the development of sustainable agricultural systems. This work was carried out at the Paulista State University, Jaboticabal campus, State of São Paulo, Brazil, during the period from February to April 2004. The objective was to analyse the community of Carabidae, Staphylinidae, Formicidae e Araneae through faunistic indexes, to determine the spatial distribution and interespecific interactions of predominant species in soybean (Glycine max (L.) Merr.), corn (Zea mays L.) and rubber tree (Hevea brasiliensis Muell. Arg.). The arthropods were sampled by pitfall traps distributed each 10 m in two …


First Report Of The Signal Fly, Scholastes Sp (Diptera: Platystomatidae) Visiting Animal Carcasses In Malaysia, Chen Chee Dhang Jan 2008

First Report Of The Signal Fly, Scholastes Sp (Diptera: Platystomatidae) Visiting Animal Carcasses In Malaysia, Chen Chee Dhang

Chen Chee Dhang

Signal fly, Scholastes sp. (Diptera: Platystomatidae) was observed associated with animal carcasses in Malaysia. The first observation was on a monkey carcass, which was killed by using a handgun and immediately placed in a forested area in Gombak, Selangor while the second observation was on a pig that died of natural causes and whose carcass was placed in an oil palm plantation in Tanjung Sepat, Selangor. Both animal carcasses were visited by Scholastes sp. flies during the fresh decomposition period. However, the role Scholastes flies in the decomposition process remains unknown. In this paper, we report the occurrence of Scholastes …


Occurrence Of Fidicinoides Pauliensis Boulard & Martinelli, 1996 (Hemiptera: Cicadidae) In Coffee Plant In Tapiratiba, Sp, Rodrigo Souza Santos Rss Jan 2007

Occurrence Of Fidicinoides Pauliensis Boulard & Martinelli, 1996 (Hemiptera: Cicadidae) In Coffee Plant In Tapiratiba, Sp, Rodrigo Souza Santos Rss

Rodrigo Souza Santos RSS

This paper presents the first register of Fidicinoides pauliensis Boulard & Martinelli, 1996 in coffee plant in the municipality of Tapiratiba, State of São Paulo, Brazil. The characterization and illustrations of the species are presented.


Potential Effect Of Anoplophora Glabripennis (Coleoptera: Cerambycidae) On Urban Trees In The United States, David Nowak, Judith Pasek, Ronaldo Sequeira, Daniel Crane, Victor Mastro Dec 2000

Potential Effect Of Anoplophora Glabripennis (Coleoptera: Cerambycidae) On Urban Trees In The United States, David Nowak, Judith Pasek, Ronaldo Sequeira, Daniel Crane, Victor Mastro

Judith E Pasek

Anoplophora glabripennis Motschulsky, a wood borer native to Asia, was recently found in New York City and Chicago. In an attempt to eradicate these beetle populations, thousands of infested city trees have been removed. Field data from nine U.S. cities and national tree cover data were used to estimate the potential effects of A. glabripennis on urban resources through time. For the cities analyzed, the potential tree resources at risk to A. glabripennis attack based on host preferences, ranges from 12 to 61% of the city tree population, with an estimated value of $72 million-$2.3 billion per city. The corresponding …


Pest Risk Assessment For Importation Of Solid Wood Packing Materials Into The United States, Judith E. Pasek, Harold H. Burdsall Jr, Joseph F. Cavey, Andris Eglitis, Robert A. Haack, Dennis A. Haugen, Michael I. Haverty, Charles S. Hodges, Daniel R. Kucera, John D. Lattin, William J. Mattson, David J. Nowak, Joseph G. O'Brien, Richard L. Orr, Ronaldo A. Sequeira, Eugene B. Smalley, Borys M. Tkaxz, William E. Wallner Jul 2000

Pest Risk Assessment For Importation Of Solid Wood Packing Materials Into The United States, Judith E. Pasek, Harold H. Burdsall Jr, Joseph F. Cavey, Andris Eglitis, Robert A. Haack, Dennis A. Haugen, Michael I. Haverty, Charles S. Hodges, Daniel R. Kucera, John D. Lattin, William J. Mattson, David J. Nowak, Joseph G. O'Brien, Richard L. Orr, Ronaldo A. Sequeira, Eugene B. Smalley, Borys M. Tkaxz, William E. Wallner

Judith E Pasek

A wide variety of exotic tree pests can readily be transported into the United States on untreated wooden pallets, crating, bracing, and other solid wood packing materials (SWPM). Recent introductions of forest pests associated with importation of SWPM demonstrate that current United States import regulations are inadequate to exclude such pests. Nearly all (97 percent) of the quarantine-significant tree pests found by port inspectors are associated with SWPM. In spite of current bark-free import requirements, about 9 percent of maritime shipments contain bark, which provides habitat for numerous organisms. A pest risk assessment was conducted for the SWPM pathway to …


Pine Shoot Beetle (Tomicus Piniperda (L.)): Pest-Initiated Pest Risk Assessment For Likelihood And Consequences Of Spread Within The Continental United States, Judith E. Pasek Mar 2000

Pine Shoot Beetle (Tomicus Piniperda (L.)): Pest-Initiated Pest Risk Assessment For Likelihood And Consequences Of Spread Within The Continental United States, Judith E. Pasek

Judith E Pasek

This pest risk assessment for pine shoot beetle, Tomicus piniperda (L.), was conducted by the United States Department of Agriculture, Animal and Plant Health Inspection Service, Plant Protection and Quarantine (USDA-APHIS, PPQ). A need to reevaluate the appropriateness of current quarantine and compliance management regulations pertaining to the Lake States and northeastern United States was identified considering the high program costs and impacts to affected industries and growers. Questions central to this issue include predictions of what levels of damage or impact might be expected should the pine shoot beetle (PSB) spread to other regions of the United States, and …


Khapra Beetle (Trogoderma Granarium Everts): Pest-Initiated Pest Risk Assessment, Judith Pasek Aug 1998

Khapra Beetle (Trogoderma Granarium Everts): Pest-Initiated Pest Risk Assessment, Judith Pasek

Judith E Pasek

This pest risk assessment was conducted by the United States Department of Agriculture, Animal and Plant Health Inspection Service, Plant Protection and Quarantine (USDA, APHIS, PPQ). It was initiated in response to a need identified during an agency Program Review for khapra beetle (Trogoderma granarium Everts; Coleoptera: Dermestidae), which was requested during the November 1997 meeting of the Plant Protection and Quarantine Strategy Team (PPQST) and the National Plant Board Council. This assessment addresses the likelihood of khapra beetle becoming established in the United States, the economic consequences of khapra beetle infestation in the US, and available information regarding pathways, …


Emergence And Overwintering Brood Of Douglas-Fir Beetle Eight Years After The Clover Mist Fire On The Clarks Fork Ranger District, Shoshone National Forest, Wyoming, Kurt K. Allen Mar 1997

Emergence And Overwintering Brood Of Douglas-Fir Beetle Eight Years After The Clover Mist Fire On The Clarks Fork Ranger District, Shoshone National Forest, Wyoming, Kurt K. Allen

Judith E Pasek

The Douglas-fir beetle outbreak on the Shoshone National Forest is evaluated for the eighth consecutive year. Adult emergence in 1996 showed a single peak. Overwintering brood in 1996 were used to predict population levels for 1997. Brood levels declined from 1995 but 81% of the overwintering brood are adults. Damage levels (number of trees killed) was at its lowest point in the last 7 years, a 4.5 fold decline from 1995. Brood counts indicate a steady or slight increase in beetle populations; however, in most areas suitable host trees are becoming scarce.

Management alternatives include salvage and sanitation, tree baiting, …


Emergence And Overwintering Brood Of Douglas-Fir Beetle Seven Years After The Clover Mist Fire On The Clarks Fork Ranger District, Shoshone National Forest, Wyoming, Judith E. Pasek Aug 1996

Emergence And Overwintering Brood Of Douglas-Fir Beetle Seven Years After The Clover Mist Fire On The Clarks Fork Ranger District, Shoshone National Forest, Wyoming, Judith E. Pasek

Judith E Pasek

Emergence patterns and population levels of Douglas-fir beetles (DFB), Dendroctonus pseudotsugae Hopkins, in the seventh year of infestation following the Clover Mist Fire were evaluated on the Clarks Fork Ranger District of the Shoshone National Forest. Adult emergence in 1995 returned to a single peak beginning in mid-June, about a week later than normal likely due to cold, wet spring weather. Adults of both the '93-'94 and '94-'95 generations emerged, demonstrating for the second year in a row that DFB can extend its life cycle up to two years. Almost half of the total emergence of the '93-'94 generation was …


Emergence And Overwintering Brood Of Douglas-Fir Beetle Six Years After The Clover Mist Fire On The Clarks Fork Ranger District, Shoshone National Forest, Wyoming, Judith E. Pasek, Willis C. Schaupp Jr Jun 1995

Emergence And Overwintering Brood Of Douglas-Fir Beetle Six Years After The Clover Mist Fire On The Clarks Fork Ranger District, Shoshone National Forest, Wyoming, Judith E. Pasek, Willis C. Schaupp Jr

Judith E Pasek

Two emergence peaks were evident for adult Douglas-fir beetles (DFB), Dendroctonus pseudotsugae Hopkins, collected from caged brood trees in 1994. The June peak resembled emergence patterns observed in previous years; however, an August peak was detected for the first time since monitoring of the outbreak began. The second peak likely resulted from delayed development of brood of the '93-'94 generation that largely overwintered as larvae. A portion of the '92-'93 generation also emerged in 1994, confirming that DFB can extend its life cycle to two years under certain conditions. The '93-'94 generation apparently also has developed an extended life cycle, …


Emergence And Overwintering Brood Of Douglas-Fir Beetle Five Years After The Clover Mist Fire On The Clarks Fork Ranger District, Shoshone National Forest, Wyoming, Willis C. Schaupp Jr, Judith E. Pasek Mar 1995

Emergence And Overwintering Brood Of Douglas-Fir Beetle Five Years After The Clover Mist Fire On The Clarks Fork Ranger District, Shoshone National Forest, Wyoming, Willis C. Schaupp Jr, Judith E. Pasek

Judith E Pasek

The emergence of adult Douglas-fir beetles (DFB), Dendroctonus pseudotsugae Hopkins, from caged brood trees in 1993, occurred from May to September, with a peak in mid- to late June. The 1993 emergence pattern is very similar to that observed in 1990 and 1992. In late fall 1993, live DFB adults were found under the bark of trees from which emergence was presumed to have been complete, because the trees had been attacked during summer of 1992. For the '92-'93 DFB generation, emerging adults were far fewer than overwintering brood, suggesting poor winter survival and/or a shift to a 2-year life …