By Blake Jackson
Potato leafhoppers, a major pest for alfalfa in Pennsylvania, have arrived from southern states. While infestations can be unpredictable, early detection is crucial to minimize damage.
These tiny, straw-colored insects weaken alfalfa plants by sucking out their juices. This disrupts nutrient flow, causing yellowing, stunted growth, and reduced protein content.
While potato leafhoppers are present from late May to frost, the most significant damage occurs during the second, third, and fourth cuttings (mid-June to mid-August).
Here's how to stay ahead of these pests:
- Scout Early, Scout Often: Regularly monitor your alfalfa fields using a sweep net. Start scouting in early to mid-June and repeat every week or so.
- Identify the Culprit: Look for pale green nymphs and disregard brown adult leafhoppers. Count the number of leafhoppers per sweep.
- Take Action When Needed: If the average number of leafhoppers per sweep exceeds the economic threshold (usually around 0.6), consider management options.
For non-chemical control, planting resistant alfalfa varieties or mixing alfalfa with other forages like orchardgrass can help. These approaches deter leafhoppers and promote natural predators like spiders.
If populations reach critical levels, early harvest or insecticides might be necessary. However, regular scouting and applying treatments only when essential helps preserve natural enemies and minimize insecticide use.
By being proactive and monitoring your alfalfa fields, you can effectively manage potato leafhoppers and ensure a healthy, high-quality crop.
Photo Credit: gettyimages-goodlifestudio
Categories: Pennsylvania, Crops, Alfalfa