ERETforce™ whitefly parasite 100 per card (5,000/ 10,000/ 15,000)

Product Description

ERETforce™ is the parasitic wasp Eretmocerus eremicus, used to control whitefly — especially the tobacco/silverleaf whitefly (Bemisia tabaci). The female lays her eggs inside developing whitefly nymphs, and the parasitized nymph turns a darker golden color as the wasp develops inside. These hanger cards deliver the pupae at 100 per card, ready to separate and hang where whitefly are building. Use it in vegetable, soft fruit, ornamental, and hemp/cannabis crops.

What it targets

• Tobacco / Silverleaf Whitefly (Bemisia tabaci)
• Other whitefly species

Crops it supports

Vegetable crops, soft fruits, ornamental crops, and hemp/cannabis — in greenhouses, indoor facilities, field and row crops, interiorscapes, and gardens.

How Eretmocerus eremicus controls whitefly

Eretmocerus is a specialist parasite that lays its eggs inside sedentary whitefly nymphs, showing a preference for 2nd instar nymphs, and it is most often used against silverleaf whitefly. It can also sting and host-feed on nymphs without laying an egg, drinking the pest’s fluids for nutrition. It works best in a window of 68–77°F with relative humidity of 70% or less, and needs whitefly nymphs present to complete its life cycle. It pairs well with Encarsia formosa when both greenhouse and silverleaf whitefly are present.

Release Rates

Preventive releases may need to be made weekly instead of bi-weekly if the crop is a “whitefly magnet.”

Cannabis Alert: Release rate suggestions on these pages are usually not sufficient for cannabis growers. For cannabis release rates, contact us.

Release Instructions

Release timing: Release the wasp pupae on cards in the early to late hours of the day after receipt. If that is not possible, avoid the hot, dry times of day. Until release, keep the strips of cards in a cool, dark space so the wasps can maximize their remaining development time.

Release method: Separate the cards at the perforations by gently folding them back and forth — don’t tear them, which can knock the delicate pupae loose, and avoid touching the pupae. Hang the cards within the canopy, protected from sun and water, distributed evenly through the crop or next to the pest’s preferred hosts. Place them in shaded areas and leave them undisturbed for about 21 days to ensure emergence. Blister packs are released the same way, with the plastic bubble giving extra protection in overhead-watered crops.

Storage: Do not cold store. It is best to apply the parasites as soon as possible upon receipt. If storage is unavoidable, keep them between 45–50°F in the dark, up to 18 hours after receipt.

Monitoring: Parasitized whitefly nymphs take 10–14 days to start appearing and often show a wound where the ovipositor contacted them. For Eretmocerus, look closely inside the nymphs for developing larvae; parasitized nymphs are left with a round, submarine-style exit hole, whereas an emerged adult whitefly leaves a T-shaped slit.

Advisories: Yellow sticky cards will catch these adult wasps as they emerge, so removing yellow cards at the time of release is ideal.