Premise While root‐order approaches to fine‐root classification have shown wide utility among wild plants, they have seen limited use for perennial crop plants. Moreover, inadequate characterization of fine roots across species of domesticated perennial crops has led to a knowledge gap in the understanding of evolutionary and functional patterns associated with different fine‐root orders. Methods We examined fine‐root traits of common horticultural fruit and nut crops: Malus × domestica , Prunus persica , Vitus vinifera , Prunus dulcis , and Citrus × clementina . Additional roots were sampled from 33 common perennial horticultural crops, native to tropical, subtropical, and temperate regions, to examine variation in 1st‐ and 2nd‐order absorptive roots. Results First‐order roots of grape and 1st‐ and 2nd‐order roots of apple and peach were consistently thin, nonwoody, mycorrhizal, and had high N:C ratios. In contrast, 4th‐ and 5th‐order roots of grape and 5th‐order roots of apple and peach were woody, nonmycorrhizal, had low N:C ratios, and were thicker than lower‐order roots. Among the 33 horticultural species, diameter of 1st‐ and 2nd‐order roots varied about 15‐fold, ranging from 0.04 to 0.60 mm and 0.05 to 0.89 mm respectively. This variation generally was phylogenetically conserved across plant lineages. Conclusions Collectively, our research shows that root‐order characterization has considerably more utility than an arbitrary diameter cutoff for identifying roots of different functions in perennial horticultural crops. In addition, much of the variation in root diameter among species can be predicted by evolutionary relationships.

Abstract Herbicide resistance is ‘wicked’ in nature; therefore, results of the many educational efforts to encourage diversification of weed control practices in the United States have been mixed. It is clear that we do not sufficiently understand the totality of the grassroots obstacles, concerns, challenges, and specific solutions needed for varied crop production systems. Weed management issues and solutions vary with such variables as management styles, regions, cropping systems, and available or affordable technologies. Therefore, to help the weed science community better understand the needs and ideas of those directly dealing with herbicide resistance, seven half-day regional listening sessions were held across the United States between December 2016 and April 2017 with groups of diverse stakeholders on the issues and potential solutions for herbicide resistance management. The major goals of the sessions were to gain an understanding of stakeholders and their goals and concerns related to herbicide resistance management, to become familiar with regional differences, and to identify decision maker needs to address herbicide resistance. The messages shared by listening-session participants could be summarized by six themes: we need new herbicides; there is no need for more regulation; there is a need for more education, especially for others who were not present; diversity is hard; the agricultural economy makes it difficult to make changes; and we are aware of herbicide resistance but are managing it. The authors concluded that more work is needed to bring a community-wide, interdisciplinary approach to understanding the complexity of managing weeds within the context of the whole farm operation and for communicating the need to address herbicide resistance.

AbstractSeven half-day regional listening sessions were held between December 2016 and April 2017 with groups of diverse stakeholders on the issues and potential solutions for herbicide-resistance management. The objective of the listening sessions was to connect with stakeholders and hear their challenges and recommendations for addressing herbicide resistance. The coordinating team hired Strategic Conservation Solutions, LLC, to facilitate all the sessions. They and the coordinating team used in-person meetings, teleconferences, and email to communicate and coordinate the activities leading up to each regional listening session. The agenda was the same across all sessions and included small-group discussions followed by reporting to the full group for discussion. The planning process was the same across all the sessions, although the selection of venue, time of day, and stakeholder participants differed to accommodate the differences among regions. The listening-session format required a great deal of work and flexibility on the part of the coordinating team and regional coordinators. Overall, the participant evaluations from the sessions were positive, with participants expressing appreciation that they were asked for their thoughts on the subject of herbicide resistance. This paper details the methods and processes used to conduct these regional listening sessions and provides an assessment of the strengths and limitations of those processes.