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Mosquitoes have long been a part of many Colorado ecosystems, but some agricultural practices have increased their populations well beyond natural levels. Mosquitoes can transmit diseases from animals to man, as well as cause serious annoyance problems. In Colorado the primary disease of concern is West Nile virus, as well as Western Equine Encephalitis, which can cause swelling of the brain and nervous system disorders in both horses and man. By monitoring and controlling mosquitoes we can prevent an outbreak of disease and greatly reduce nuisance problems. Irrigated lands are among the highest producers of mosquito breeding sites in Colorado. High numbers of mosquitoes can develop in standing water as a result of flood irrigation. By taking the actions below, you can help prevent the spread of disease, and control mosquito nuisances by using physical controls, in place of biologicals and chemicals. Actions you can take on your irrigated properties:

  • Minimize standing water in fields to less than four days by improving drainage channels.

  • Tail waters should not be allowed to accumulate for more than 4 days at the end of the field.

  • Keep ditches clean of heavy vegetation to promote more rapid drainage and prevent impeded flow of irrigated waters.

  • Have ditches repaired to reduce seepage

  • To report standing water which cannot be eliminated or to report standing water in other areas please call Colorado Mosquito Control Toll-Free at (877) 276-4306. CMC can control mosquito larvae without chemicals.