Incidence of insects, diseases, and other damaging agents in Oregon forests.

Abstract

The Forest Service of the U.S. Department of Agriculture is dedicated to the principle of multiple use management of the Nation's forest resources for sustained yields of wood, water, forage, wildlife, and recreation. Through forestry research, cooperation with the States and private forest owners, and management of the national forests and national grasslands, it strives-as directed by Congress-to provide increasingly greater service to a growing Nation.The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, age, disability, and where applicable, sex, marital status, familial status, parental status, religion, sexual orientation, genetic information, political beliefs, reprisal, or because all or part of an individual's income is derived from any public assistance program. This report uses data from a network of forest inventory plots sampled at two points in time, annual aerial insect and disease surveys, and specialized pest damage surveys to quantify the incidence and impact of insects, diseases, and other damaging agents on Oregon's forests. The number and volume of trees damaged or killed by various agents is summarized. Differences in the frequency and severity of damaging agents between various ownership categories and geographic regions of the state are investigated.

Pest risk assessment of Atropellis spp. for the EU territory

“…Considering the lower impact observed in other Pinus spp. in North America (Schubert, ; Dunham, ; Cerezke et al., ), this impact assessment could be regarded as a worse‐case scenario. However, Heineman et al.…”

“…Considering the lower impact observed in other Pinus spp. in North America (Schubert, 1974;Dunham, 2008;Cerezke et al, 2014), this impact assessment could be regarded as a worse-case scenario. However, Heineman et al (2010) studied Atropellis impacts within a range of temperatures which is well below what commonly experienced in many areas of the EU where lodgepole pine has been planted.…”

“…The prevalence, i.e. the percentage of forest stands that are affected within an affected wood‐production area was estimated based on the evidence that the pest has been found: occasionally (general remark in Hansen, ), in 27% (Heineman et al., ; sample size = 66 plots), 37% (Roach et al., ; sample size = 27), 46% (Van der Kamp, ; 28 locations), 52% of stands (Hopkins and Callan, ; 169 sampled stands) and in many stands (general remark in Dunham, ).…”

Transformation of western hemlock (Tsuga heterophylla) tree crowns by dwarf mistletoe (Arceuthobium tsugense, Viscaceae)

“…Previous crown mapping efforts have not targeted T. heterophylla infected with Arceuthobium tsugense despite its contribution of unique canopy structures and volume across Northwest forests (Shaw et al, 2004;. In Oregon it is estimated 10.8% of all T. heterophylla are infected with A. tsugense and that 7% of those are moderate or severe (Dunham, 2008). Crown architecture and volume impacts have been more easily studied in forests where tree crowns are more visible or accessible such as in Pinus contorta Douglas ex Loudon or P. ponderosa Douglas ex P. Lawson & C. Lawson (Agne et al, 2014;Godfree, Tinnin, & Forbes, 2002, 2003Hoffman et al, 2007).…”