by Leanne Pundt, UConn Extension and Tina Smith, UMass Extension
Biological control
Using biological controls against aphids (especially the foxglove aphids) has been challenging for growers. Growers uncertain about the aphid species, have been using mixes of different natural enemies. Growers often begin with a mixture of wasps, Aphidius colemani (for green peach and cotton aphid) and Aphidius ervi (for the larger potato and foxglove aphids) as preventative, or when numbers are low. The parasitic wasp, Aphelinus abdominalis has also been used for potato and foxglove aphids.
Photo: D. Gilrein, Cornell
The predatory midge, Aphidoletes aphidimyza, can be used as clean up, now that the days are longer. Lacewings can also be used to clean up aphids in hot spots. Some growers use lacewing larvae that are shipped in rice hulls that are ready to hatch or they use adult lacewings.
Chemical control
- Aria (flonicamid - Group 9C), Contact and systemic activity, selective feeding blocker. (Not for viola or pansy). Aphids quickly stop feeding.
- Endeavor (ornamentals), Fulfill (edibles) (pymetrozine –Group 9B), Translaminar activity, selective feeding blocker. When aphids feed on treated plants, the aphids stop feeding within hours after treatment and eventually starve to death. However, the aphids will continue to be present for 2 – 3 days after ingesting the material.
- Mainspring (cyantranilprole- Group 28), Translaminar and systemic activity. Apply as a preventative drench on aphid prone ornamentals. Aphids stop feeding and become paralyzed after ingestion.
- Rycar (pyrifluquinazon – Group 9B), Contact and translaminar activity. Aphids quickly stop feeding.
The Rutgers IR-4 Program has a summary of what has been working based upon research reports across the country. According to this report, Aria, Endeavor, Mainspring (used preventively) and Rycar all exhibited good to excellent control and are non-neonicotinoids.
Source: UMass Amherst