Tip Top Bio-Control Technical Bulletin

Metaphycus helvolus
Black Scale Parasitic Wasp

Target Pests:
These tiny, black and yellow wasps are effective against several soft-scale species, including brown scale, black scale, hemispherical scale and nigra scale.

Description:
Metaphycus helvolus is a parasite (wasp). The females lay their eggs under the body of first and second stage scales. The grubs feed on scales and develop into adults within 2 weeks. Adults also provide control by feeding on non-parasitized scales.

Product Information:
Metaphycus is shipped in 100, 200 or 500/cup.

Release Rates:
Metaphycus are most effective in semi-tropical conditions or below 90°F. Do not release in heavy rains. After removing the lid on the container place the container in infested plant so insects will fly out on their own. Remove the lid and tap bottom of container for faster release.

Release rates: 5-10 per infested plant, 2-3 weeks after reducing heavy populations with soap. Release adults at 2-3 week intervals and as necessary thereafter. Monitor plants weekly and manually remove mature adult scale to facilitate control. Good control can be expected within 28-32 days. 1,000/acre.

Inside this insect prefers to fly to a sunny window or the brightest place located inside. Metaphycus will return to the plants when the light diminishes. To avoid this behavior shade the window or release at dusk.


Strategic Considerations:
It is not recommended that Metaphycus is stored more than one day past the arrival date. If you need to store, store in a cool, dark place that is approximately 60°F. Do not refrigerate or place Metaphycus directly next to cold packs.