The Distribution of Saperda Inornata and Oberea Schaumii (Coleoptera: Cerambycidae) within the Crowns of Large Trembling Aspens, Populus Tremuloides

The larvae of Saperda inornata Say and Oberea schaumii LeConte inhabit the stems of trembling aspen (Populus tremuloides Michaux) root suckers and the twigs of larger trees. Nord et al. (1972a, 1972b) reported the biologies of these species in Upper Michigan and northern Wisconsin. S. inornata has a one or two year life cycle, probably depending on how early the egg is laid. Most (77.5%) 0. schaumii develop in three years while 5.0% require only two years and 17.5% require four years to develop. Knight (1963) described the distribution of galleries made by S. inornata and 0. schaumii in the crowns of large trembling aspen, P. tremuloides, in Upper Michigan. Similar distribution data were gathered from 180 large trembling aspen felled in a survey designed to determine the relative abundance of S. inornata and 0. schaumii in stands of different site quality (Nord and Knight 1972b). The analysis of that distribution data and comparisons with that of Knight (1963) are presented here. Inter- and intra-specific competition in light of the results and other behavioral information are discussed

The Relationship of the Abundance of \u3ci\u3eSaperda Inornata\u3c/i\u3e and \u3ci\u3eOberea Schaumii\u3c/i\u3e (Coleoptera: Cerambycidae) in Large Trembling Aspen, \u3ci\u3ePopulus Tremuloides\u3c/i\u3e, to Site Quality

Saperda inornata Say and Oberea schaumii LeConte are cerambycids that inhabit the stems of trembling aspen, Populus tremuloides Michaux, root suckers and the twigs of larger trees. The biologies of those species in northern Wisconsin and Upper Michigan were reported by Nord et al. (1972a and 1972b). S. inornata oviposits on the cambium under horseshoe- or shield-shaped egg niches gnawed in the outer bark by the female. The term egg niche, connotes an oviposition place prepared by the female using the mandibles and ovipositor (Linsley 1959). There are usually 2 or 3 egg niches at one level on the stem or twig, and a globose gall consisting of callus tissue forms there. The larvae feed in the cambial and callus tissue around the gall and require 1 or 2 years to complete development. The 0. schaurnii female gnaws an elongate, rectangular egg niche in the outer bark and deposits an egg on the cambium beneath it. The larva bores downward from the egg niche in the wood. Most individuals require 3 years to complete the life cycle; but some take only 2 years, while others take 4 years. A survey designed to determine the importance of the egg niches and galleries of S. inornata and 0. schaumii as infection courts of Hypoxylon pruinatum (Klotzsche) Cke. in large trembling aspen was begun in 1962 in Iron and Ontonogan Counties, Michigan. The data from that survey indicated that abundance of borers might be correlated with the site quality of the stand. Therefore in 1963 the survey was redesigned to detect differences in abundance between stands of different site quality. Since the redesign concerned only the selection of stands, not the sampling procedures used within the stand, most of the trees sampled in 1962 were incorporated into the redesigned survey. The data collected in conjuction with the survey also make possible conclusions regarding the distribution of borer galleries within the crowns of large trees. Those results and a discussion of competition between S. inornata and 0. schaurnii are given in another paper (Nord and Knight, 1972a). The incidence of H. pruinatum in the galleries was reported by Nord and Knight (1972b)

The Importance of Saperda Inornata and Oberea Schaumii (Coleoptera: Cerambycidae) Galleries as Infection Courts of Hypoxylon Pruinatum in Trembling Aspen, Populus Tremuloides

(excerpt) Trembling aspen, Populus tremuloides Michaux, and bigtooth aspen, P. grandidentata Michaux, are hosts of numerous species of injurious insects and microorganisms (Harrison 1959). Only a few of those organisms, however, are directly responsible for mortality of healthy trees. The fungus Hypoxylon pruinatum (Klotzsche) Cke. is most important in that respect, killing 1-2%o f the standing volume annually in the Lake States (Anderson 1964). It invades and spreads in cambial tissue, killing it and eventually the branch or stem by girdling. Initially, a canker appears as a sunken, yellowish-orange area in the bark (Anderson 1956). In a later stage the outer bark raises in blister-like patches and sloughs off exposing blackened, crumbling cortex

Thermoplasmonics: Quantifying plasmonic heating in single nanowires

Plasmonic absorption of light can lead to significant local heating in metallic nanostructures, an effect that defines the sub-field of thermoplasmonics and has been leveraged in diverse applications from biomedical technology to optoelectronics. Quantitatively characterizing the resulting local temperature increase can be very challenging in isolated nanostructures. By measuring the optically-induced change in resistance of metal nanowires with a transverse plasmon mode, we quantitatively determine the temperature increase in single nanostructures, with the dependence on incident polarization clearly revealing the plasmonic heating mechanism. Computational modeling explains the resonant and nonresonant contributions to the optical heating and the dominant pathways for thermal transport. These results, obtained by combining electronic and optical measurements, place a bound on the role of optical heating in prior experiments, and suggest design guidelines for engineered structures meant to leverage such effects.Comment: 17 pages, 4 figures + 3 pages supporting materia

List Size, Standards and Perfromance in General Practice - A Pilot Study in the South East Thames Region

This is a report of a piolt study carried out among 155 general practitioner trainers in South East Thames region. Similar pilot studies have been carried out among trainers in four other regions on England. Separate reports have been prepared for each of the five regions, together with a summary report comparing the findings among the regions. The pilot studies were funded by the DHSS and carried out by staff of the Health Services Research Unit at the University of Kent at Camterbury

Unemployment and wages in South Africa: A spatial approach

A large amount of recent evidence finds a negative relationship between local unemployment and wages in OECD countries, a relationship christened a ‘wage curve’. This contradicts the conventional model of the labour market in which high unemployment regions have higher wages to compensate for search and other costs. This paper discovers a wage curve in South Africa, a country with several times the typical unemployment rate of OECD countries. The wage curve elasticity in South Africa is similar to that in OECD countries (-0.1) but persists over a much larger range of unemployment rates, implying that unemployment can have a large impact on wages in South Africa. However, this wage flexibility does not extend to union wages which are well insulated from local unemployment conditions. The results here also shed light on the segmentation of the labour market based on labour immobility and on the debate about the appropriate definition of unemployment in South Africa.wages, unemployment, wage curve, South Africa

Review: Postmodern Art Education in Practice. Gude, O. (Ed.). (n.d.). Spiral Art Education

Book review of Spiral Art Education, Olivia Gude (Editor), University of Illinois, Chicago, 2003

Global/local stress analysis of composite panels

A method for performing a global/local stress analysis is described, and its capabilities are demonstrated. The method employs spline interpolation functions which satisfy the linear plate bending equation to determine displacements and rotations from a global model which are used as boundary conditions for the local model. Then, the local model is analyzed independent of the global model of the structure. This approach can be used to determine local, detailed stress states for specific structural regions using independent, refined local models which exploit information from less-refined global models. The method presented is not restricted to having a priori knowledge of the location of the regions requiring local detailed stress analysis. This approach also reduces the computational effort necessary to obtain the detailed stress state. Criteria for applying the method are developed. The effectiveness of the method is demonstrated using a classical stress concentration problem and a graphite-epoxy blade-stiffened panel with a discontinuous stiffener

The Geographic Variation of Saperda Inornata Say (Coleoptera: Cerambycidae) in Eastern North America

Excerpt: During the summers of 1962 and 1963 a study of the life history and behavior of what was thought to have been Saperda moesta LeConte in trembling aspen, Populus tremuloides Michaux, was completed in northern Michigan (Nord, 1968). After the field study, it became apparent that the original identification was doubtful. Furthermore, there was a possibility that two species were present in the study areas, thus the biological data collected may have represented not one but two species