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Agrilus cuprescens (Ménétries, 1832), the rose stem girdler, is a Palearctic Buprestidae (Coleoptera) pest of Rosa and Rubus species. Its introduction and consequent spread across North America may now make it the most widely distributed Agrilus species, globally.No evidence reviewed indicated A. cuprescens was present in North America long before it was first reported on Rosa in New Jersey, USA, in 1913. The species incrementally progressed westward, reaching the Pacific coast in Washington, USA, 101 years later. Future spread is most likely within the northern Canadian prairies and the Pacific Northwest regions. Its presence in the latter region poses a contemporary threat to epicentres of Rubus production in both the United States and Canada. As of 2022, confirmed spread within the region extended nearly to the Canadian border in Washington and the southern Willamette Valley in Oregon.The most comprehensive, foundational investigations of A. cuprescens in North America were conducted in the late 1930s and early 1940s in New York, USA, and in Utah, USA, during the late 1950s and early 1960s following damaging outbreaks on Rubus. Ongoing research in the Pacific Northwest is attempting to refine information on this pest as it progresses towards naturalization within a new North American ecological and agricultural context.This review aggregates and clarifies the geographical progression, biological understandings and management of this species in North America, which has been fraught with a convoluted history of misidentifications, and varying degrees of consideration given to it as a pest of concern. [ABSTRACT FROM AUTHOR]

Eulophid larvae discovered in galleries of Agrilus cuprescens (Ménétries, 1832) within canes of Rubus sp. (Rosaceae) in the Pacific Northwest, U.S.A. region between 2018 and 2021 were identified as Baryscapus rugglesi (Rohwer, 1919) (subfamily Tetrastichinae). This species had previously only been found in eastern North America. Identification was based on numerous specimens reared from larvae collected from eight disparate locations in western Oregon and Washington State, U.S.A., in 2019 and 2021, and examination against its type series from 1919 in Minnesota, U.S.A. and specimens from 1938 in New York, U.S.A (Mundinger 1941). Both sexes of B. rugglesi are herein redescribed and illustrated. Additionally, DNA sequences from specimens collected in 2019 were direct sequence matches with original specimens collected in 2018. The ubiquitous occurrence of B. rugglesi suggests it is likely a predominant parasitoid of A. cuprescens in the region. Baryscapus rugglesi is a gregarious larval parasitoid of several native Agrilus spp. in North America, so it is presumably native to the Nearctic region and has adapted as an alternative parasitoid of A. cuprescens, a Eurasian-native pest introduced into North America. However, COI sequences of B. rugglesi were similar to those of an unidentified eulophid from Europe in the Barcode of Life Database (almost 96% identity), possibly indicating a Holarctic distribution. Observed wasp biology, behavior, and perspectives on the potential role of B. rugglesi as a natural enemy within integrated pest management programs for A. cuprescens control are discussed. [ABSTRACT FROM AUTHOR]

Replacing summer fallow practices with annual legumes as green manures (LGMs) may increase the sustainability of northern Great Plains wheat (Triticum aestivum L.) systems. Viability hinges on soil water use management and realizing biologically fixed nitrogen (N) benefits. Plot-scale research has shown that managing LGMs with first-flower stage termination and no-till practices conserves soil water and that rotational N benefits can increase wheat grain quality. Nonetheless, farmer adoption of LGMs has been negligible. To better understand this practice and its regional adoption potential, we conducted a participatory on-farm assessment of no-till LGM versus summer fallow-wheat rotations in north-central Montana. Soil water and nitrate (NO3) levels to 0.9 m (3 ft), potentially mineralizable N (PMN) to 0.3 m (1 ft), wheat yields, conservation potential, and producer adoption challenges were assessed at five farmer-managed, field-scale sites. Compared to fallow, LGM treatment diminished mean wheat yield by 6% (0.24 Mg ha-1 [3.7 bu ac-1]), diminished grain protein by 9 g kg-1 when wheat was fertilized with N (p = 0.01), and increased grain protein by 5 g kg-1 when wheat was unfertilized (p = 0.08). Small soil water depletions in LGM treatments below fallow at wheat seeding (17%; 30 mm [1.2 in]) and near-record high rainfall during the wheat growing season (280 to 380 mm [11 to 14 in]) suggest that LGMs likely did not limit soil water available to wheat in this study. Soil NO3 levels following LGMs were 29% to 56% less than summer fallow at wheat seeding, and conversely, greater PMN was detected in LGM treatments at 3 of 5 sites. We theorize that N mineralization from LGMs was insubstantial by wheat seeding due to dry soil conditions and low LGM biomass N contributions, consequently affecting wheat yield potential due to limited early season soil N availability. LGMs increased average use efficiency of available N by 24% during the wheat year and increased total residue carbon (C) and N returned to soils by 260 and 26 kg ha-1 (232 and 23 lb ac-1), respectively, after two years. Our results illustrated that farmers viably managed LGM soil water use with early termination and no-till practices but that LGM adoption may be hindered by a lack of immediate wheat yield or protein benefits from legume-N and seed costs for LGMs. Appropriate incentives, management strategies, and yield benefit expectations (short versus long term) should be fostered to increase the adoption potential of this N-economizing soil and water conservation strategy. [ABSTRACT FROM AUTHOR]