Arkansas Fruit, Vegetable and Nut Update

Potential Impact of Melonworm on Pumpkins in 2026

by Aaron Cato - August 27, 2026

Melonworm adults were observed in Northwest and Northeast Arkansas on August 20 and 21. (Picture 1). Although adults were found on pumpkin plants, no larvae have been observed as of August 26 at any location.

Melonworm is a tropical species that immigrates from sub tropical portions of the US every year. This means that the date of first observation and density of melonworm infestations by early-mid August often paints a clear picture of risk faced by pumpkin growers (Picture 2).

Melonworm Arrival in the last 6 years

Year	First Melonworm Observation	State Impact
2020	9/03 in NW AR	Sporadic Infestations
2021	9/7 in NW AR (Likely late-July)	Widespread Losses
2022	9/19 in NW AR	Sporadic Infestations
2023	10/10 in NW AR, 8/30 in SW AR	Few Issues (Some damage in SW AR)
2024	8/08 in NW AR, 8/15 in SW AR	Widespread Losses
2025	8/26-27 in NW, C, NE AR. 8/19 in SW AR	Widespread Infestations

A brightly colored melonworm moth adult sits on a pumpkin leaf

Picture 1. Melonworm adult observed on a pumpkin leaf near Fort Smith, Arkansas, on August 20, 2026. Photo by Ryan Keiffer.

In 2025 melonworm were observed at several locations across the state and damage was evident where growers failed to respond with insecticides. However, density of infestations pailed in comparison to 2024 and was nowhere near the impact we observed in 2021. In 2025, melonworm larvae were first observed infesting pumpkin plants in Arkansas on August 19 in Hope and on August 26 and 27 in Fort Smith, Conway, and Newport. Larvae being observed mid-August indicate that adult moths could have been observed in early-August, and it is likely that a much larger and impactful infestation of melonworm will be observed mid-September once they cycle to the next generation

So, what should we expect this year? Unless larvae are found in high densities in the next week, it is unlikely that pumpkins are at a high risk of injury in 2026. With the lack of tropical weather systems and very dry weather, it is unlikely that melonworm will thrive outside of cultivated cucurbits, and are unlikely to accelerate into a much larger generation by October. However, it is still possible that isolated farms will still see large levels of injury. Every year we have scouted for melonworm we have found at least one farm that needed to be sprayed, even in years where melonworm wasn’t observed until late September. We still recommend scouting at least weekly, and expecting melonworm to be present at some point this fall.

See our fact sheet, “Managing Melonworm in Pumpkins and Squash in the Mid-South” for further recommendations on control measures and risk of injury by pumpkin variety. If you observe any melonworm moths or adults on your farm with weeks still left before harvest is complete, we recommend beginning sprays to suppress rind feeding.

As always, give me a call at 479-249-7352 if you have any questions.

A combo picture showing melonworm larvae on a leaf, on a young shoot, and on a maturing pumpkin.

Picture 2. Melonworm larvae observed feeding on the underside of leaves near the mid rib, in new growth that has been silked together, and on the rind of maturing pumpkins. These images depict the signs of initial infestations of this impactful pest. Photos by Ryan Keiffer.