The first visual sign of damage is yellowing of leaves, especially on new growth. This yellowing often occurs in V-shaped wedges and is referred to as hopperburn. Severe damage causes stunted plants with shortened internodes. Stunting and leaf loss result in poor hay quality, reduced tonnage, and occasionally the loss of an entire cutting. Long-term losses include reduction in plant vigor that reduces winter hardiness.
Stunted alfalfa allows light penetration into the canopy, encouraging weed growth.
Severe hopperburn on alfalfa. Potato leafhopper adult. As alfalfa cutting progresses, adult potato leafhoppers often hopscotch among neighboring fields. The regrowth of subsequent cuttings must be scouted carefully. Considerable damage can be caused by large populations of leafhoppers moving from a cut field to the new regrowth of an adjacent field.