We have heard of and observed increasing potato leaf hopper (PLH) damage in many areas across OH last week. PLH feed similar to aphids, by piercing and sucking on plants causing stunting, thinning and yellowing of alfalfa, often called hopperburn. To scout fields, use a sweep net—a single sweep sample is a set of 10 sweeps, and choose 5-10 different field locations. Treatment is needed if the number of PLH (adults and nymphs) caught a sweep sample is equal to the height of alfalfa. For glandular haired or PLH-resistant alfalfa, the threshold is multiplied by 3. For older, thinning alfalfa stands, thresholds can also be increased, while newer stands (e.g. new seedings or 1st year) are more vulnerable. See Ohio State University Extension Bulletin 545, Control of Insect Pests of Field Crops (https://agcrops.osu.edu/publications/control-insect-pests-field-crops-bulletin-545), for those insecticides labeled for potato leafhopper, or for all insecticides labeled on alfalfa.
Don’t get burned by hopper burn: Potato Leafhoppers reaching high levels in alfalfa and forage
Crop Observation and Recommendation Network
C.O.R.N. Newsletter is a summary of crop observations, related information, and appropriate recommendations for Ohio crop producers and industry. C.O.R.N. Newsletter is produced by the Ohio State University Extension Agronomy Team, state specialists at The Ohio State University and the Ohio Agricultural Research and Development Center (OARDC). C.O.R.N. Newsletter questions are directed to Extension and OARDC state specialists and associates at Ohio State.