312 Arboriculture & Urban Forestry 2006. 32(6):312–313. ARBORICULTURAL ABSTRACTS ANALYZING THE SPREAD OF BEECH CANKER Nicole H. Augustin, Edgar Kublin, Berthold Metzler, Elsa Meierjohann, and Georg von Wühlisch We investigate the spread of Nectria canker of beech, which is a fungal chronic disease caused by Nectria ditissima Tul. et C. Tul. Data are available from a beech provenance trial. A possible influential factor on the proportion of infected trees per plot is the wind dispersal zone(s) (wdz), a categorical variable describing the distance and wind direction from dis- eased shelterwood, the source of infection. We investigate the effect of wdz and whether the disease incidence in the regen- eration can be explained alone by the wdz using different approaches accounting for spatial correlation in the data. One method uses generalized estimating equations (GEE) where, through specification of a general variance–covariance matrix allowing for nonindependence, spatial correlation can be ac- counted for in the model. The second method uses general- ized additive models (GAM) and the spatial autocorrelation is dealt with by modeling it as a spatial trend. The third method uses generalized linear mixed models (GLMM) with a ran- dom effect accounting for spatial correlation and heterogene- ity. We show that, in the beech data, some spatial correlation is present that is over and above that accounted for by the wdz. Therefore, methods not accounting for this correlation are inappropriate. The GLMM is the most appropriate model because it manages to model the biological process best: It explains the variation in disease incidence by the wdz and by secondary infection. Hence it yields the most precise esti- mates. (Forest Science 2005. 51(5):438–448) FIELD EVALUATIONS OF SYSTEMIC INSECTICIDES FOR CONTROL OF ANOPLOPHORA GLABRIPENNIS (COLEOPTERA: CERAMBYCIDAE) IN CHINA Therese M. Poland, Robert A. Haack, Toby R. Petrice, Deborah L. Miller, Leah S. Bauer, and Ruitong Gao Anoplophora glabripennis (Motschulsky) (Coleoptera: Cer- ambycidae), a pest native to China and Korea, was discovered in North America in 1996. Currently, the only reliable strat- egy available for eradication and control is to cut and chip all infested trees. We evaluated various doses of the systemic insecticides azadirachtin, emamectin benzoate, imidacloprid, and thiacloprid for control of A. glabripennis in naturally infested elms (Ulmus spp.), poplars (Populus spp.), and wil- lows (Salix spp.) in China between 2000 and 2002. Signifi- cantly more dead A. glabripennis adults were found beneath elm and poplar trees treated with imidacloprid (in 2000 and 2001) or thiacloprid (in 2001) and beneath willow trees in- ©2006 International Society of Arboriculture jected with imidacloprid or thiacloprid (in 2002) compared with control trees. In 2000, 4 months after injection, the den- sity of live A. glabripennis was significantly reduced in pop- lar trees treated with imidacloprid (90%) and in willow trees treated with imidacloprid (83%) or emamectin benzoate (71%) compared with controls. In 2001, 9 months after in- jection, the density of live A. glabripennis was significantly reduced in poplar (76%) and willow (45%) trees treated with imidacloprid compared with control trees. Similarly, percent- age mortality of all life stages of A. glabripennis feeding within trees was significantly higher on poplar trees 4 months after injection with imidacloprid (64%) in 2000 and on elms (55%) and poplars (63%) 9 months after injection with imi- dacloprid in 2001 compared with control trees. Imidacloprid residue levels in leaves and twigs collected at various times from 1 day to 9 months after injection ranged from 0.27 to 0.46 ppm. Injecting A. glabripennis-infested trees with imi- dacloprid can result in significant mortality of adults during maturation feeding on leaves and twigs and of all life stages feeding within infested trees. Imidacloprid is translocated rapidly in infested trees and is persistent at lethal levels for several months. Although, injection with imidacloprid does not provide complete control of A. glabripennis, systemic insecticides may prove useful as part of an integrated eradi- cation or management program. (Journal of Economic Ento- mology 2006. 99(2):383–392) ROLE OF URBAN GREENWAY SYSTEMS IN PLANNING RESIDENTIAL COMMUNITIES: A CASE STUDY FROM EGYPT Khalid Zakaria El Adli Imam Greenways have long played a significant role in the devel- opment of urban and sub-urban areas. They help mitigate the loss of “natural” space, often have scenic qualities, provide for recreation, education, a sense of well-being, and preser- vation of the natural habitat. This article explores the concept, history and development of urban greenways. The article il- lustrates the concept of linked parks and urban greenways in structuring urban and sub-urban developments while suggest- ing a methodological blueprint for their implementation in the planning process. A case study of a suburban development west of the city of Cairo, Egypt is presented to demonstrate the role of urban greenway systems in planning residential communities. An in-depth investigation of the planning pro- cess, context, approach, and development concept is followed by an overview of the rationale and significance of the method. The objective of this article is thus twofold. First, to
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