Centennial State News

Mesa County and the city of Grand Junction have reported an 85% reduction in Japanese beetle populations following a successful summer treatment plan. The beetle, first found in Grand Junction during the summer of 2022, was declared a public nuisance by Mesa County in March 2023. Efforts to eradicate the species involved collaboration with the Colorado Department of Agriculture (CDA), CSU Extension, and local authorities.

Wondirad Gebru, Director of the Plant Industry Division at CDA, noted the success: “We saw a significant reduction in the number of beetles we found through our trapping efforts.” He attributed this success to joint efforts with fruit producers and local partners.

The eradication project began in July 2023, with initial treatments applied earlier that spring. After two years of treatments, only 830 beetles were trapped compared to 5,716 in 2023.

Mesa County Commissioner Bobbie Daniel expressed pride in their progress: “Thanks to the dedicated efforts...we are proud to report such a significant reduction in Japanese beetle numbers.” She emphasized their commitment to monitoring and treating affected areas to protect agriculture and the economy.

In 2024, CDA granted $110,000 to Mesa County for treatment costs. The Japanese beetle poses a threat to crops like peaches and grapes and can infest over 300 plant species.

Previously, Mesa County managed a similar infestation discovered by a Master Gardener in 2002. Quick action led to a 99% population reduction over five years without significant crop damage.

To safeguard state industries, an intrastate quarantine prevents importing commodities carrying Japanese beetles from affected regions into non-quarantined areas like Mesa County. The Pest Control Act authorizes CDA to establish such quarantines.

CDA’s Plant Industry Division also provides various programs related to crop production and environmental health while regulating hemp producers and plant imports.