What producers, land managers, and forage professionals need to know as Florida’s response takes shape. 

At a glance. The pasture mealybug was first detected in Florida in May 2026; it has now been reported in 22 Florida counties, including the panhandle. Its spread, broad range of hosts, and uncertain biology make prevention and coordinated response especially important. 

Authored by: Dr. Marcelo Wallau, UF/IFAS Forage Extension Specialist  

Pasture Mealybug 

Pasture mealybug (PMB) is a small, soft-bodied insect that specializes in grasses. Unlike the better-known mealybugs that affect citrus or ornamental plants, this pest can feed on a wide range of grass hosts—including forage grasses, agronomic crops, turf, roadside vegetation, and weeds. That broad host range makes it a landscape-level concern rather than a problem confined to a single crop. 

The insect is thought to have originated in South Asia, and became a significant problem in Australia beginning in 1926, with concern increasing from the 1990s onward. The first reports in production systems in US were in Texas in 2025, although researchers there speculate that damage reports back from 2022 could be associated with PMB. In Florida, this pest was first confirmed in May 2026. Likewise, it may have been present before formal detection, but its apparent rapid movement and crop injury have raised the urgency of the current response. 

Why it is difficult to manage 

Pasture mealybug inhabits the lower canopy, often in the thatch layer, and can migrate into the soil or beneath cattle dung patties for protection and overwintering. Those protected locations make the insect hard to find and hard to reach with conventional insecticide sprays. In fact, broad-spectrum contact insecticides can do more harm to natural predators and will not reach the PMB. Labeled products are still limited, and research on the effectiveness of insecticides for PMB control in different crops is still underway.   

Scientists are also investigating whether what is currently called pasture mealybug may include two variants—or potentially two distinct species—which complicates the issue even further. Scientific literature on PMB is limited. If the new variant is actually a new species, then much of the biology and ecology of the PMB needs to be revisited. This is important to understand for multiple reasons. First, knowing the natural range can help us find biological control alternatives for this insect. Second, understanding the cycles is essential for refining management practices to target the most effective timing and stages to control the bug. 

Prevention begins with limiting movement 

Pasture mealybug can easily be moved around with people, equipment, animals, and vegetation clippings. Sanitation can significantly prevent movement and new infestations, and is one of the most practical tools available right now. Farm machinery, tractors, ATVs, side-by-sides, clothing, livestock, and wildlife can all help move mealybugs between locations. 

• Learn where the PMB is. Inspect the lower canopy, thatch, soil surface, and areas beneath dung pats when scouting. 

• Clean equipment and clothing after working in infested or suspect areas. 

• Isopropyl alcohol 70% may be used for cleanup clothing or small tools; for equipment, remove plant and soil debris with a blower, and, when possible, wash/pressure wash with soap (dish or insecticidal soap)  

• For landscape crews, avoid moving contaminated material off site. 

• Change clothes before moving from a suspect site to another pasture, farm, or managed landscape. 

Our group has put together several handouts with guidelines that can help prevent spread. You can access those through: https://entnemdept.ufl.edu/pasture-mealybugs/publications/

What early management work suggests 

We have multiple research projects underway to better understand this pest. Moreover, a lot of the knowledge that we have compiled so far comes from the observations and immediate response from our farmers. The pest appears less prevalent in grazed pastures and more common in tall, dense canopies such as hay fields, stockpiled forage, and limpograss planting material. Good soil fertility—particularly adequate potassium and phosphorus—may help pastures tolerate injury. As an example, it seems that sugarcane in the fertile muck soils is less affected. On the other hand, excessive nitrogen fertilization seems to favor infestation. We have just launched a new producer-driven research project to sample soil and plant tissue to correlate nutrient levels and management practices to PMB infestation. We also know that not all forage species and sugarcane varieties have the same amount of damage, indicating different levels of tolerance. One of our research projects is already looking into species and variety susceptibility to PMB. 

We have multiple trials on both sugarcane and forages to evaluate insecticide effectiveness. Preliminary results from Florida, Louisiana, and Texas have variable outcomes. First, the timing of application relative to the level of infestation is essential. Early applications seem to be more effective, but detection remains a problem. Often, when symptoms are visible, the infestation is well advanced, and the damage is there. The natural fluctuations in the insect population have been a confounding factor in our trials, and we still don’t have reliable data on this insect’s biology. 

Systemic insecticides, especially neonicotinoids, have shown better results so far, but there is variation among the outcomes for different products. Imidacloprid and thiamethoxam achieved greater PMB control than flupyradifurone, while contact insecticides such as pyrethroids had no effect. Despite that, we have seen that even with 80% insect control in sugarcane, there is still significant crop damage, and the cane is not recovering. Pastures seem to bounce back better, but a new cycle of infestation starts somewhere around 21 days. It appears that damage is more related to the presence than to the abundance of PMB.  

Given the time of the year (late-summer), a major concern is for stockpiling forage now. This is a very important practice in preparation for the winter, and could create a perfect environment for PMB development. We do not have data on how long insecticides can delay a new infestation, but we speculate that an application of thiamethoxam, for example, around 15 days after cutting or staging the pasture for stockpile, could give an extra 21 days of some level of protection. Although this is highly speculative, it will not likely provide the necessary protection to carry that pasture into the fall and early winter for deferred grazing. Cutting infested areas for hay may offer a management option to avoid total loss of forage. However, data from Texas indicates that PMB can still live in hay bales even 30 days after cutting, which makes hay another source of dispersion of mealybugs. 

A coordinated response  

UF/IFAS and the Florida Department of Agriculture and Consumer Services (FDACS) have organized a pasture mealybug task force, co-led by colleagues from both institutions. The group is connecting with sugarcane, cattle, and turf stakeholders and building a communication strategy that includes a website, social media outreach, webinars, roundtables, handouts, training sessions, and regular updates. Since this pest is affecting other states and is now being considered an agricultural crisis, USDA-ARS and APHIS recently organized a national summit with UF, FDACS, Texas A&M, LSU, industry stakeholders, and others to coordinate multi-state action and identify rapid and longer-term solutions. 

Research outcomes are often at a slower pace than the demand for information from our farmers, who are making immediate decisions on this pest. We understand the urgency. Our approach is to provide the best reasonable recommendations based on the current information, with the understanding that they are preliminary. Thus, the recommendations are likely to change over time.  

The road ahead 

Although we were monitoring the expansion of the problem in Texas, we were not expecting this pest to come to Florida and expand across the state so fast. Still, we were able to respond to it swiftly immediately after the first confirmed case. Many of our faculty shifted their attention almost completely to tackle this pest. Nevertheless, the response has not been sufficient. We are now reorganizing our group to add more dedicated personnel to the different fronts in investigation and to secure funding for more research and extension work.  

In conversations with industry stakeholders, and based on the evidence we have so far, it is unlikely and unsustainable—on many fronts—that we will “spray our way” out of this pest. Effective management will likely depend on coordinated prevention, scouting, agronomic management, and, especially, biocontrol. The number of acres that can potentially be affected or harbor this pest is enormous, and it will take a combined effort between individual producers, public managers, and the allied industry to tackle this pest. Roadside rights-of-way, natural areas, public utilities, and water-management districts all intersect with the pest’s potential habitat and movement pathways. Sustained coordination—and adequate support for researchers and response teams—will be essential as Florida develops practical guidance. 

Stay informed 

Pasture mealybug is spreading quickly, and we have more questions than answers at this point. At the same time, we are generating a lot of information that can help us mitigate the effects of this pest. For current updates and educational materials, visit https://go.ufl.edu/pasturemealybugs or follow the UF/IFAS Forage Team on Facebook – UF/IFAS Forages and Instagram at uf.forages. 

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