Over the years of Kerb use in lettuce (more like decades) there has been a lot of work on application methods. Our transplanted lettuce in southern California is usually grown on drip and when possible, we like to apply all things through it. Our fields are surrounded by four cities and folks there just don't seem to enjoy sprayer rigs that much.
At the UC Hansen Research & Extension Center (clay loam soil) we applied Kerb at 2.5 and 5 pints/A rate either via drip or bed spray. The herbicide was applied with second irrigation after transplanting of ‘Inferno' romaine (great name for green lettuce). The irrigation continued after Kerb application to assure moisture movement from drip tape past the plant...
Automated lettuce thinners that use a spray mechanism to remove unwanted lettuce plants and weeds have been widely adopted in the Salinas Valley and desert production districts. The machines utilize a camera to capture images of the lettuce plants in the seedline, calculate plants that need to be removed and those that will be kept (keepers) and then it activates a spray mechanism treat the unwanted plants. The spray mechanism has advantages over mechanical devices (e.g. swinging or spinning blades) because they do not disturb the soil or cut roots, and in addition, they have less inertia and can be quicker in responding to a signal from the computer. However, spray mechanisms can potentially drift or wafting control materials onto the...
The following information is from the Salinas Valley Agriculture blog.
On January 12, 2016 the Federal EPA label for Kerb SC was reinstated for leaf lettuce. The registration on leaf lettuce was pulled in 2009 and Dow AgroSciences has been working to reregister Kerb since that time. As part of this reregistration effort, Kerb was reclassified as “not likely to be carcinogenic to humans” which freed up space in the risk cup. Of particular interest are the preharvest intervals allowed in the label:
- Author: Richard Smith
Richard Smith, Farm Advisor and Tricia Love, Research Assistant
University of California Cooperative Extension Monterey County
The current automated weeding machines use cameras to detect plants, and a computer algorithm to process the image, calculate which plants to keep/remove, and activate a kill mechanism. These machines are capable of cultivating within the seedline and removing weeds that would otherwise be left by traditional cultivation. The machines used in these studies included the Robovator, F Poulsen Engineering Aps, Hvalsø, Denmark and Steketee IC Weeder, the Netherlands. Both of these machines use a split knife that as it...
Weed control in cool-season vegetables can be quite challenging. However, there are a number of practices that provide growers with certain advantages:
- Short-season crops such as lettuce and spinach that allow for rapid turnover of the crops (e.g. 30 to 65 days), frequent cultivation (lettuce) and/or complete hand removal of weeds prior to mechanical harvest (clipped spinach and baby lettuce)
- High value of the crops allows for the use of intensive hand-removal of weeds, often prior to seed set
- Small production blocks that allow for careful observation and intensive management
All of these strategies have basically made some of the most troublesome weeds such as field bindweed and yellow...