This Season With the produce season winding down rapidly, now is a good time to reflect on pest activity and insecticide usage you experienced this season in desert lettuce. The 2022 Lettuce Crop Losses Workshop will be held live, in-person Wednesday, April 20th at the Yuma Agricultural Center from 11:30 until 3:00 pm (see agenda below). Get there early as lunch will be provided. The meeting has been approved for 2.5 CA/AZ CEUs. Participants will be asked to complete two short surveys to document pest pressure and control tactics used on lettuce this season. This workshop has been invaluable to our Vegetable IPM Team over the past 18 years because it allows us to develop accurate “real world” data on crop losses and pesticide usage which is important to the assessment of IPM programs in Arizona. It’s also valuable to PCAs, as it can translate their efforts into economic terms for their growers and confirms their value to the lettuce industry by showing the importance of key insect pests and their cost-effective management in desert lettuce production. It's no secret, the insect activity this year was exceptional, particularly for aphids. Lettuce and green peach aphids are still quite abundant on romaine in our late season trials at the Ag Center. As I’ve reported previously, I think this is by far the heaviest aphid year I’ve seen since Lettuce aphid was first reported in Yuma in 2000. Previous Lettuce Insect Losses surveys from theses workshops estimated that over a 15-year period, PCA made on average 1.5 sprays on lettuce for aphids (ranging from 1.0 to 2.5 sprays). For the complete report see: Insect Losses and Management on Desert Lettuce: A 15-year Summary. Based on reports from PCAs this spring, it is likely that considerably more sprays were applied this spring. Also, a wide variety of insecticides products were reportedly used by PCA’s, some with mixed results. You can review the historical database of insecticides used for aphids and other insects here: Insecticide Usage on Desert Lettuce, 2020-2021. The bottom line: from a historical perspective, it would be quite useful to document aphid pressure and sprays applied this year compared to previous years. If results from the workshop show that aphid pressure was indeed heavier this year, then we can start asking why, and perhaps what we can do differently in the future. Finally, Marco Pena will be providing the latest results of herbicide trials and his areawide weed survey, and I will be providing the latest efficacy trial results on lettuce aphids, thrips, worms, and whiteflies. So, we hope you can make it to the workshop and participate in this important process.

Lettuce Crops Losses Workshop April 20, 2022 11:30-3:00 pm
Yuma Agricultural Center Conference Room
Agenda
11:30-12:00 pm Lunch (It will be yummy)
12:00- 12:30 pm Impact of IPM on Lettuce Insect Losses John Palumbo
12:30-1:00 pm Individual Completion of LIL Questionnaires Attendees
1:00-1:30 pm Historical Results of Insect Losses /Insecticide Usage John Palumbo
1:30-2:00 pm Weed Management Research Update Marco Pena
• Recent herbicide trials
• Areawide weed surveys
2:00-3:00 pm Insect Management Research Update John Palumbo
• Worm and Whitefly efficacy trials
• Spring aphid and thrips efficacy trials
• INSV update