| Life Cycle: | The adult aster leafhopper is olive-green with six black spots on the forehead. The abdomen is pale grey-green and the wings are opaque. It can be confused with the potato leaf hopper which is bright green and lacks the black markings on the forehead. Its movement is governed by weather patterns. It often arrives in Canada from the southern U.S. States carried by the northern jet stream passing over wheat fields where the leafhopper has overwintered. The eggs of the aster leafhopper can overwinter in the leaf folds of winter grains. In May and June as the grains mature, the leafhoppers move to more preferred crops such as grasses and vegetable crops. |
| Host: | Aster leafhoppers have been noted on over 150 species of host plants. In vegetable crops they are attracted to carrots, parsnips, celery and lettuce. They also like weeds common in Atlantic Canada such as thistle, chickory, wild carrot, dandelion and plantain. |
| Bio Region: | The aster leafhopper in present in most regions in North America. It is more prevalent in the southern U.S. states. Its migration destination is weather dependent. Overwintering local egg populations require 130 degree days above nine degrees Celsius to hatch into nymphs. |
| Damage: | Aster leafhoppers spread the Asters Yellow pathogen (AYP). To transmit the pathogen it must first acquire it by feeding for a period of time on an infected host. Many of the numerous host plants for AYP are the same host plants for aster leafhopper. The pathogen must incubate in the leafhopper for approximately 3 weeks, so most of the spread of AYP is from leafhoppers that have migrated from the U.S. Aster Yellows symptoms in carrots begin with the youngest leaves turning first yellow, then red and possibly even purple. The carrots themselves can be elongated and bitter and ultimately unmarketable. |
| Management: | Cultural options include the planting of varieties resistant to aster yellows. Weed control in headlands and ditches to reduce the presence of host plants including: lambs-quarters, ragweed, stinkweed, quackgrass and pineappleweed. |
| Controls: | There are no allowable treatments for AYP. For this reason control measures focus on resistant varieties of crops and elimination of host plants for both AYP and leafhoppers.
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