Vegetable crops

The market for organic vegetables is increasing. As conventional farmers transition fields to organics to meet this demand, there is a need for better organic nutrient management guidance, especially for nitrogen (N). Organic N management is more challenging than conventional N management due to a higher level of uncertainty surrounding the N supplying capacity of an organically managed soil as well as the constraints of organic fertilizers (supply, application timing and placement, and uncertainty of release rate and amount). As a result, conventional nutrient management strategies may not be appropriate for organically managed systems. With organic N management there is often a higher risk of excessive nitrate-N loss and higher risk of not achieving economic yield targets.

Several new powdered limestone products that are more finely ground (smaller particle size distribution) than products historically used have become commercially available. A major factor influencing the effectiveness of a liming material is its particle size distribution, with smaller particles reacting more quickly. Because lime efficiency estimates for various particle size fractions were established in the 1950’s, there is a need to evaluate current guidelines to determine if they adequately predict liming efficiency for these new products. The objective of this study was to assess the reactivity of commercially available powdered lime products (both calcitic and dolomitic) and various particle size fractions over a year with the goal of evaluating current OSU lime guidelines.

This year, we commemorate 20 years of OSU’s VegNet (1996-2016). VegNet has become a well-known and utilized resource for processed vegetable growers, researchers, and Ag professionals throughout Oregon. This regional program provides weekly activity reports for common broccoli, cauliflower, sweet corn, and snap bean pests. The main goal of the program is to serve as an early warning and detection network, to inform growers of potential pest outbreaks that may warrant increased field scouting and action. Notable trends from 2016 include extensive Cabbage Looper pressure, a continued increase of Cucumber Beetle species (12-spot and striped), and new Armyworms to be aware of. It is becoming apparent that pest activity can vary widely between field sites. Although the regional average is useful, it should not be the only metric used when considering if and how to treat for pests.