On this page
How to identify it
- Adult females are oval, 2 to 5 mm long and coated in white wax, with short tube-like projections at the rear. Older ones grow fine white hairs about as long as their body is wide, sticking out on all sides.[1][3][4]
- In the field they look like bits of white lint stuck to the grass, and they cling to shoes and pant legs as little white dots.[2][3][4]
- Mature mated females turn pink. The youngest nymphs are under 1 mm, some as small as 0.2 mm, and need a magnifier; adult males are tiny winged insects seen in summer, sometimes in swarms.[1][4]
- The two species can't be told apart in the field, and in Texas H. novovillei is thought to be the more common one.[1]
Look-alikes
| Look-alike | How to tell them apart |
|---|---|
| Rhodesgrass mealybug | Its damage can be confused with pasture mealybug's, but under a hand lens rhodesgrass mealybugs have dark, rounded, cottony bodies with long waxy filaments at the rear and legless adults; pasture mealybugs are more elongate, have short rear filaments and keep their legs.[4] |
| Drought, low fertility and other grass pests | Yellowing, reddening and stunted patches are often taken for low fertility or drought, and cold, herbicide injury and other pests such as ground pearls cause similar symptoms. Look for the mealybugs themselves at the edges of damaged patches.[1][4] |
Where it lives
Described from Queensland, Australia, in 1928, the pasture mealybug is also known from Asia, the Caribbean (first found in the Western Hemisphere in 2019-2020) and Mexico. In the United States it was confirmed in Texas in 2025, then in Louisiana sugarcane, Florida limpograss and, in August 2026, Decatur County, Georgia.[1][4][3][2]
Biology and life cycle
They live at the base of grass plants, on roots, on the undersides of lower leaves, in thatch, at or just below the soil surface and under dried cow patties. All stages can move.[1][3][4]
The nymphs do the damage; adults feed little if at all. Mating takes place in the thick summer thatch, and a female can produce nearly 100 offspring in a day.[1][4]
They are most active in warm, humid months, especially after rain. In Texas the young may begin emerging in early April, with damage showing from June. There are about three generations a year, with numbers peaking from late summer into fall.[4][1][3]
In cool or dry weather they retreat underground or under cow patties and thatch, where nymphs feed on roots as deep as 3 feet; females can survive the winter in the soil.[4][1]
They spread on the wind, in runoff, and on equipment, vehicles, livestock, clothing, hay, sod and potted grasses. Mowing an infested field can leave a smoke-like cloud of mealybugs behind the mower.[4][2][3]
Hosts are warm-season grasses, including bahiagrass, bermudagrass, Johnsongrass, crabgrass, sorghum-sudangrass and bluestems, plus sugarcane and some sedges. Legumes, brassicas and other broadleaf plants are not affected.[3][1][4]
Damage and signs
- Nymphs suck sap and inject a saliva that is toxic to the grass. Weakened plants become more open to infection by pathogens such as Fusarium, and the combination, called pasture dieback, kills the grass; even low numbers can cause it under the right conditions.[1][2][3]
- Symptoms can appear within a week: grass yellows, then turns purple or red, starting at the tips of older leaves. Plants look stunted and drought-stressed even after rain, with poor roots. Patches spread and merge, and in extreme cases whole fields are affected.[1][4][3]
- Mississippi State sums up the signs as PMB: purpling, messiness from the lint-like mealybugs and the sooty mold growing on their honeydew, and bareness as the grass dies.[3]
- A killed hay field can take two years to fully reestablish.[3]
Health risk
It is a grass pest; the Texas A&M, UGA, Mississippi State and USDA sources mention no risk to people, and USDA notes it is not known to transmit any pathogens.[1][2][3][4]
Control
Prevention
For badly damaged fields, seed-producing grasses such as bahiagrass and bluestems may reseed. Starting over means removing all the old grass, and Mississippi State suggests replanting with forages the mealybug doesn't attack, such as tall fescue or pearl millet.[1][3]
Sanitation
Slow the spread: pressure wash or sweep equipment before moving it from infested fields, avoid driving through pastures unnecessarily, change or clean footwear and clothing after walking an infested field, keep grazing records and limit traffic onto the farm.[2][4]
Traps and physical control
Scout often. Check the edges of yellowing or reddening patches rather than the dead centers, the undersides of lower leaves, and the thatch and soil surface; in hay 14 to 30 days after cutting, pull the stems back at the soil line and look for clusters of mealybugs.[1][3][4]
Cut or shred and bale the grass, or graze it hard. The mealybugs thrive in tall, dense forage, and opening the canopy also lets any insecticide reach them.[1]
Pesticides
Insecticide options are limited and still being tested; none gives complete control. Products that work need green regrowth of about 6 to 8 inches after cutting and may work less well in drought. Which products are allowed differs by state (Texas, Mississippi and Georgia each list different emergency or labeled options), so check with your county Extension office.[1][2][3]
Skip pyrethroids, fipronil and carbaryl: they proved ineffective in Texas trials. Texas A&M also advises against broad-spectrum carbamates, organophosphates and pyrethroids because they kill the predators and parasites needed for lasting control.[1]
When to call a professional
Report suspected pasture mealybugs from a new county to your county Extension agent so the spread can be tracked.[1][3][2]
Common questions
- Can pasture mealybugs get into my lawn?
- They have turned up in turfgrass, including St. Augustinegrass in Texas and centipedegrass in Georgia, but they prefer the thick canopy of pastures and hay fields. Mississippi State says regularly mowed, well-managed lawns are less likely to be attacked, and UGA says it isn't yet clear whether they will be a turf problem.[2][3]
- How do I tell pasture mealybug damage from drought or low fertility?
- Look for the mealybugs themselves. Check the edges of yellow or reddish patches, the lower leaves, the thatch and the soil surface; the grass also looks drought-stressed even after rain.[1][4]
- Will a pyrethroid spray take care of them?
- No. Pyrethroids were ineffective against pasture mealybugs in Texas trials, and they kill the natural enemies that help keep the mealybugs down.[1]
Sources
- Texas A&M AgriLife Extension Service, “The Pasture Mealybug: A New Invasive Pest of Pastures and Hayfields in Texas.” agrilifeextension.tamu.edu/pasture-mealybug/ (accessed 2026-11-08)
- University of Georgia College of Agricultural and Environmental Sciences, “UGA experts track pasture mealybug's arrival in Georgia (CAES Field Report, September 2, 2026).” fieldreport.caes.uga.edu/uga-experts-track-pasture-mealybugs-arrival-in-georgia/ (accessed 2026-11-08)
- Mississippi State University Extension Service, “MSU scientists urge farmers to scout for new invasive pest (September 15, 2026).” extension.msstate.edu/news/feature-story/2026/msu-scientists-urge-farmers-scout-for-new-invasive-pest (accessed 2026-11-08)
- USDA APHIS PPQ, Cooperative Agricultural Pest Survey program (hosted by Purdue University CERIS), “Heliococcus summervillei Datasheet, Version 1.0 (March 26, 2026).” caps.ceris.purdue.edu/heliococcus-summervillei-datasheet_v1/ (accessed 2026-11-08)
- iNaturalist, “Heliococcus novovillei taxon page (order and family).” www.inaturalist.org/taxa/1706786 (accessed 2026-11-08)