Ed Weber

Priority risk factors for back injury in agricultural field work: vineyard ergonomics

ABSTRACT With support of a NIOSH Community Partners grant, the authors reviewed data from three cooperating vineyard companies in Napa and Sonoma Counties, finding both high rates of evidence of musculoskeletal disorders (MSDs) and identifying priority MSD hazards for intervention. Data from OSHA 200 injury report logs identified 29 reported MSDs and 435 lost workdays in a working population of 194 in a 30-month period. The majority of these (20) involved backstrain. High risk job tasks were identified, including: employer-identified tasks, analysis of injury reports, and ergonomics risk factor checklist survey of task work. Triangulating across these three data groups resulted in identification of high priority tasks, including: hand harvest work, hand pruning, and weeding using shovels. Priority risk factors for back injury in these jobs were: repetitive lifting of heavy loads, repetitive exertion of force by the trunk and upper extremities, and repetitive or sustained awkward postures of the trunk (including full stoop and twisting with loads).

High Risk Tasks for Musculoskeletal Disorders in Agricultural Field Work

Agricultural work involves heavy physical exertion and is characterized by evidence of high rates of musculoskeletal disorders. Currently ergonomics is a low priority for injury and illness prevention in agriculture. However, based on costs and incidence rates ergonomics risk factors should rank among the highest farm safety priorities. Analysis of field work jobs by the University of California with support from NIOSH yield an industry generalizable set of high risk tasks which should have high intervention priority. These are: repetitive and awkward forward flexion, repetitive lifting and carrying heavy loads, and highly repetitive hand work.

Testing the Efficacy of Barrier Plantings for Limiting Sharpshooter Spread

Barrier plantings have been used successfully in the management of plant diseases. Their effectiveness at limiting the incursion of the blue-green sharpshooter (Graphocephala atropunctata), an important vector of the pathogen Xylella fastidiosa, into vineyards was evaluated. Four barrier treatments (three tree species plots and one open control plot) were established and sharpshooters were monitored regularly over eight years. Barriers had intermittent effects, with significantly lower abundance of sharpshooters adjacent to tree plots in one year and significantly lower trapping frequency in three of the eight years. This inconsistency suggests that, on their own, barriers are likely to be an incomplete strategy for limiting pathogen spread into vineyards.

Severe Pruning of Infected Grapevines Has Limited Efficacy for Managing Pierce’s Disease

After the initial infection, bacterial plant pathogens often localize to specific tissues or within certain parts of their hosts. In such cases, it may be possible to clear the infection by removing the infected portion and retraining the plant from the base of the trunk. We tested the efficacy of severe pruning at clearing grapevine infections by Xylella fastidiosa, the causal agent of Pierce’s disease. We surveyed vines in six Northern California vineyards and rated them on a scale of disease severity from 0 to 3. Next, we aggressively pruned vines by removing the trunk 10 cm above the graft union and we monitored their retrained canopies over time. Although 82% (284/346) of severely pruned vines appeared disease free the following season, the prevalence of symptoms in conventionally pruned control vines suggests that more than one-third (112/324) of vines would have recovered without severe pruning—at least those with less advanced symptoms. Moreover, for five of the six vineyards, the majority of severely pruned vines showed symptoms of Pierce’s disease by the time vines were retrained, two seasons after pruning (as high as 81%, 86/106; 71% overall, 245/346). These results suggest that severe pruning does not clear X. fastidiosa infection from grapevines to an extent that would justify its adoption for disease management.