Enaphalodes rufulus (Haldeman) (red oak borer; Coleoptera: Cerambycidae) is a native wood borer that colonises and develops in oaks (Quercus Linnaeus; Fagaceae) across southeastern Canada and the eastern United States of America. It is rarely considered a pest because it normally occurs at low population density levels in stressed or dying oak trees. In the late 1990s and early 2000s there was a large, historically unique outbreak of E. rufulus in the Ozark mountains of Arkansas and Missouri, United States of America. This outbreak provided an opportunity to investigate within-tree spatial distribution of attacks during unusually high insect population levels. Fifty trees from northern Arkansas were felled and destructively sampled. The locations of attack sites by female E. rufulus were standardised across varying heights and diameters for comparison across trees. Attack sites showed a significant clustered pattern within trees. Attack sites were aggregated towards the lower and middle bole, and on the south-facing side of trees. This pattern has been seen in other insects, including wood borers, and is potentially related to differences in temperature. These patterns of ovipositional behaviour in outbreak situations have implications for E. rufulus resource partitioning and facultative intraguild predation among larvae.

We analyzed nitrogen (N) content in phloem and xylem of 75 northern red oak, Quercus rubra L. (Fagaceae), removed in 2002–2007 from three sites within the Ozark National Forest, Arkansas, to investigate the relationship between vascular tissue N status and wood borer infestation. Populations of native red oak borer, Enaphalodes rufulus (Haldeman) (Coleoptera: Cerambycidae), experienced an outbreak and population crash during the sampling period. Vascular tissue N was not correlated with borer infestation density (exit holes/m−2/bark surface), which suggests variation in N status of vascular tissue was not influenced by or did not influence borer success. Vascular tissue N was greater in trees sampled during winter months than in trees sampled in spring and summer months.

The red oak borer, Enaphalodes rufulus (Haldeman), is a native wood-boring beetle implicated as a major contributor to recent high levels of oak mortality in northern Arkansas. Northern red oaks, Quercus rubra L. (Fagaceae), were grouped into three classes of red oak borer infestation history based on crown condition and basal red oak borer emergence holes: class I (low infestation), class II (moderate infestation), and class III (high infestation). In 2004 and 2005, trees from each class were mechanically wounded and callus formation was measured after one year. Class I trees exhibited significantly greater callus formation than class III trees in both years. Monthly measurements in spring and summer of 2006 indicated significant differences in callus formation among classes, with class I trees healing over significantly earlier. Moisture was measured in bark samples removed 1 week and 4 weeks after initiation of three treatments: control, mechanical wounding, and artificial insertion of larvae. Moisture levels did not vary among infestation classes or treatments. This research indicates that bark moisture is likely not a defense against red oak borer, but that callus overgrowth may be a defense early in the second year of the life cycle in healthy trees.

Studies were conducted in the summer and fall of 2001 in North Brunswick, NJ, and Marion County, Oregon, to evaluate the response of glyphosate-resistant and glyphosate-susceptible creeping bentgrass hybrids, colonial bentgrass, redtop, and dryland bentgrass grown as individual plants to postemergence (POST) herbicides. Glyphosate at 1.7 kg ae/ha, glufosinate at 1.7 kg ai/ha, fluazifop-P at 0.3 and 0.4 kg ai/ha, clethodim at 0.3 kg ai/ha, sethoxydim at 0.5 kg ai/ha, and a combination of glyphosate and fluazifop-P were applied 6 wk after planting. Glyphosate provided almost complete control of all susceptible bentgrass species at 4 weeks after treatment (WAT). Glufosinate provided 95% or greater control of all bentgrass species at 4 WAT, but regrowth was observed on all species in the summer experiment in Oregon. Fluazifop-P, clethodim, and sethoxydim provided slower control of bentgrass species, which ranged from 38 to 94% at 4 WAT, depending on species, herbicide, and experimental location. By 8 WAT, fluazifop-P at 0.4 kg/ha applied alone or in combination with glyphosate showed the highest levels of control (>90%) across all bentgrass species. Studies were also conducted in 2002 in the spring and summer in North Carolina to evaluate the response of a mature stand of glyphosate-susceptible ‘Penncross’ creeping bentgrass to POST herbicides. Two applications of glyphosate at 1.7 kg/ha were required to achieve 98% bentgrass control at 8 WAT. Fluazifop-P at 0.4 kg/ha, clethodim at 0.3 kg/ha, and sethoxydim at 0.4 kg/ha exhibited herbicidal activity, but two applications were required to reach (>82%) control of bentgrass at 8 WAT. Two sequential applications of clethodim or the combination of glyphosate and fluazifop-P provided 98% control of bentgrass at 8 WAT. Of the other herbicide treatments evaluated, only atrazine and sulfosulfuron provided (>80%) control at 8 WAT. The results of these studies demonstrate that fluazifop-P, clethodim, and sethoxydim have substantial herbicide activity on bentgrass species and may be viable alternatives to glyphosate for control of glyphosate-resistant creeping bentgrass and related bentgrass species in areas where they are not wanted. Glufosinate, atrazine, and sulfosulfuron also exhibited substantial herbicidal activity on bentgrass, and further research with these herbicides is warranted.

As early as 1844, it was stated that the size of the host may influence the size of parasitoid adults (Ratzeburg 1844) and that parasitoid size may affect fecundity (Salt 1941). Although positive relationships between host and parasitoid body size have been supported in the literature (Tillman and Cate 1993; Heimpel and Rosenheim 1995), this relationship is not universal to all host–parasitoid systems (King 1991; Morse 1994). Although the relationship between host size and body size of parasitoid adults has been observed for some bark beetle parasitoids (Bushing 1967; Samson 1984), the relationship between body size and fecundity has not been studied for bark beetle parasitoids. Roptrocerus xylophagorum Ratzeburg (Hymenoptera: Pteromalidae) is a bark beetle parasitoid with a wide host range that includes beetles in the genera Dendroctonus, Ips, and Sc