# Whitefly

> Small white-winged sap-sucking insects of the family Aleyrodidae, mainly Trialeurodes vaporariorum and Bemisia tabaci, that fly up when disturbed and coat leaves in honeydew.

- Canonical: https://genetixbay.com/knowledge/glossary/whitefly.html
- Also written: whiteflies, white fly, greenhouse whitefly, Trialeurodes vaporariorum, silverleaf whitefly, sweetpotato whitefly, Bemisia tabaci
- Glossary category: Pests and diseases · Evidence: Established
- Status: Draft: awaiting expert review · Updated: 2026-10-31
- Licence: CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0/), attribute "GenetixBay cannabis glossary"

Whiteflies are sap-feeding insects of the family Aleyrodidae, about 1-2 mm long, with powdery white wings held over the body. The two that matter on cannabis are the greenhouse whitefly (*Trialeurodes vaporariorum*) and the silverleaf or sweetpotato whitefly (*Bemisia tabaci*). Adults fly up in a cloud when a plant is shaken. Nymphs are flat, oval and fixed to leaf undersides like tiny scales.

## In practice

Feeding yellows leaves and deposits honeydew, which grows black [sooty mould](https://genetixbay.com/knowledge/glossary/sooty-mould.md). *Bemisia* is also a virus vector; whitefly-transmitted lettuce chlorosis virus has been reported on cannabis. [Yellow sticky traps](https://genetixbay.com/knowledge/glossary/sticky-trap.md) catch adults and show population trends. [Biological control](https://genetixbay.com/knowledge/glossary/biological-control.md) uses *[Amblyseius swirskii](https://genetixbay.com/knowledge/glossary/amblyseius-swirskii.md)* against eggs and young nymphs, [parasitic wasps](https://genetixbay.com/knowledge/glossary/aphidius.md) (*Encarsia* and *Eretmocerus* species) and [entomopathogenic fungi](https://genetixbay.com/knowledge/glossary/entomopathogenic-fungi.md). *Bemisia* populations resist many insecticide groups, so [prevention](https://genetixbay.com/knowledge/glossary/cultural-control.md) and biocontrol carry more weight than sprays. Check what is registered for cannabis locally.

## Don't confuse with

- **Aphids**: no wings in most colony members; they walk rather than fly up.
- **Fungus gnats**: dark grey flies that hover near the medium.
- **Mealybugs**: waxy and crawling, never flying.

## Related terms

[Aphid](https://genetixbay.com/knowledge/glossary/aphid.md), [Amblyseius swirskii](https://genetixbay.com/knowledge/glossary/amblyseius-swirskii.md), [Sticky trap](https://genetixbay.com/knowledge/glossary/sticky-trap.md), [Beauveria bassiana](https://genetixbay.com/knowledge/glossary/beauveria-bassiana.md), [Plant virus](https://genetixbay.com/knowledge/glossary/plant-virus.md)

## Read more

- [Whiteflies on cannabis: life table, temperature, parasitoids and IPM](https://genetixbay.com/knowledge/pests/whiteflies.md)

## Sources

1. UC IPM. Pest Notes: Whiteflies (Publication 7401). https://ipm.ucanr.edu/PMG/PESTNOTES/pn7401.html
2. UConn IPM. Biological Control of Whiteflies. https://ipm.cahnr.uconn.edu/ipm-biological-control-of-whiteflies
3. UMass Extension. Whiteflies on greenhouse crops. https://www.umass.edu/agriculture-food-environment/greenhouse-floriculture/fact-sheets/whiteflies-on-greenhouse-crops