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Plain Language Summary: Poa annua is a troublesome weed in turfgrass areas such as golf courses, athletic fields, lawns, and sod farms. Controlling P. annua is made more difficult by the growing problem of herbicide resistance, the inherited ability of plants to survive herbicide applications that would normally be lethal. Researchers from 13 academic institutions collected 866 P. annua populations from different states and turfgrass systems to better understand the extent of this problem. Collections were divided and treated with four herbicides and one plant growth regulator. Plants were categorized as “susceptible” or “suspected resistant” based on their response to treatments. Suspected resistance (to at least one or more treatments) was observed in 16.8% of P. annua collections. Herbicide resistance in P. annua is a problem spanning different geographies and management practices. Therefore, coordinated research is needed to explore the scope and nature of the problem in a systematic way. [ABSTRACT FROM AUTHOR]

The western portion of the Pacific Northwest is known for being dry in the summer and cool and humid in the other months. Tall fescue is valued for its drought and heat tolerance, making it a desirable choice in regions where water is scarce and often restricted by legislation during periods of drought in the summer. However, cool and humid climates make it challenging to manage tall fescue in the winter because unacceptable quality is often observed due to low-temperature diseases and thinning in turf. A field trial was initiated in Autumn 2020 in Corvallis, OR, USA to assess the effects of mowing height as well as fertility timing and rate on tall fescue performance. Two mowing heights of 5.1 and 7.6 cm, four seasonal fertility timings, and three levels of annual N rates of 98, 196, and 294 kg⋅ha-1⋅yr-1 were evaluated using a 2 x 4 x 3 factorial experiment in a strip-plot design. Quantitative data of percent green cover and normalized difference vegetation index (NDVI) suggest that autumn fertilization is needed in cool, humid areas where tall fescue is actively growing in the winter months. The annual fertilization rate of 294 kg⋅ha-1⋅yr-1 N produced higher green turf cover and NDVI, compared with 98 or 196 kg⋅ha-1⋅yr-1 N. Furthermore, divergent effects of mowing heights were observed during winter compared with other months, suggesting that tall fescue could be mowed lower at 5.1 cm during cool, humid winter months and higher at 7.6 cm in other seasons for better overall turfgrass growth and less winter disease and thinning. Our research provides practical cultural practices for managing tall fescue turf in the Pacific Northwest or similar climates. [ABSTRACT FROM AUTHOR]

Oregon Statute requires all Oregon schools to adopt an integrated pest management (IPM) plan, create a list of acceptable low-impact pesticides, designate an IPM Coordinator, participate in annual training for IPM Coordinators, and provide periodic training for other school employees. To assist Oregon schools in meeting the requirements of the Oregon IPM in schools law, we developed an engaging and needs-based IPM training curriculum for public school IPM Coordinators and grounds employees in the Portland Metropolitan area. We used a focus group and survey to identify high-priority training topics. These topics were (1) landscape rodent management, (2) landscape and turf weed management, (3) hardscape weed management, (4) building a low-maintenance landscape, and (5) maximizing low-impact pesticides. We conducted site visits to confirm the severity of these issues and determine if other IPMrelated topics need to be incorporated into the future training events. Four separate training events were held in two different school districts. The four training events collectively reached 66 employees from 15 of the 23 school districts in the Portland area. On-site surveys were used to assess the quality of the training; follow-up focus group interviews and an on-line survey were used to quantify the impacts of this training. According to the survey, the majority of the participants (67%) felt the training improved their knowledge of turf and landscape IPM. Final assessment determined that the majority of attendees have used the provided take home material (85.7%) and plan to decrease pesticide use by using the skills they learned (71.4%). [ABSTRACT FROM AUTHOR]