Calf diarrhea (scours) is a major animal health challenge for cattle producers because it causes dehydration, depression, mortality, and long-term reduction in vitality of infected animals. Enterotoxigenic E. coli (ETEC; K99) and enterohemorrhagic E. coli (EHEC; e.g., serovars O157:H7, O26 and O111) can cause enteric colibacillosis in calves, and EHEC strains are also significant food […]
Reduced tillage can improve soil quality and reduce fossil fuel use. Adopting reduced tillage in organic production poses challenges because farmers rely on tillage as a primary means of weed management and for incorporating soil amendments to maintain soil fertility and quality. Recent research on organic reduced tillage has focused on mechanically terminated and mulched […]
Research conducted in the 2009-10 and 2010-11 growing seasons had three main components: a winter wheat-winter pea intercropping study, developing an inter-row cultivator with precision guidance for in-season weed management, and a new pea breeding project. (1) Intercropping: The potential use of winter peas as a nitrogen (N) resource for winter wheat was evaluated in […]
In previous studies, we showed that apples, strawberries, and tomatoes grown with organic nitrogen fertilizer sources had higher phytochemical contents than those fertilized with readily available sources of nitrogen. It is also possible that increased pest herbivory in the field stimulates plant defenses that elevate these phytochemicals in organic crops. To test the relative contributions […]
Organic vegetable growers in western Washington pass over their fields 10 to 20 times annually with tillage equipment ranging from spring tooth harrows to mold board plows. Soil preparation activities such as plowing, rototilling, and even spading pulverize large‐bodied soil organisms and reduce soil carbon storage and aggregates. Successful reduced tillage in organic agriculture relies […]
Biological control by naturally-occurring predatory insects and spiders is an ecologically friendly and sustainable approach to pest management. Biological control is often underutilized, however, in part because we know little about how to successfully conserve predators to maximize their impacts on pests. Here, in Washington potato fields, we investigated the effects of planting wildflower insectaries […]
Tomato, eggplant, and watermelon can be significantly impacted by Verticillium wilt, a soil-borne disease common throughout Washington. Verticillium microsclerotia are known to persist in soil for over 13 years. Symptoms impact plants later in development after most production costs have been incurred, resulting in a 25-100% crop loss in some years even when ground has […]
This study focused on adapting a disease forecasting system called WISDOM for use in managing late blight in organic specialty potato production systems of western Washington. Although disease forecasting models in crop production are generally known to reduce unnecessary fungicide sprays and fungicide application costs, none have been developed with late blight and organic potato […]
SUMMARY Effects of an alfalfa cover crop on biological control of pear psylla and tree nutrition was assessed. The bullet points below summarize findings. Experimental Orchard (Moxee) • substantial increase in predator densities on orchard floor associated with alfalfa cover crop • no correlative effect on predator numbers in trees • no effects of cover […]