Mosquitoes in Central Oregon


Pro Tip

The higher the rivers rise, the more mosquitoes we’ll have. Read the whole article for tips on how to decrease mosquito numbers in your area.


Mosquito issues in Central Oregon tend to vary year-to-year depending on seasonal snowpacks and summer temperatures, which can cause rapid rising of rivers and flooding of nearby meadows and marshes. Those meadows and marshes contain mosquito eggs that were deposited last year or in previous years. The eggs will hatch when the rivers rise high enough to reach the eggs. The higher the rivers rise, the more mosquitoes we will have. This will create problems for people near the rivers and may move into subdivisions within a few miles of the rivers.

MosquitoesYou’re not immune to more mosquitoes if you live away from the rivers. If you live in flood irrigated areas with cattle, you’ll also see an increase in mosquitoes this year. Typically, flood irrigation farmers and ranchers tend to over-water their pastures in very warm times with ample water. This creates longer standing water sources for mosquitoes, and because those pools are shallow, they stay very warm. Mosquitoes can go from egg to adult in less than 7 days with these conditions, and then the cycle starts over.

Ideally, mosquitoes are controlled in the larval stage, which prevents them from becoming blood feeding adults, but in Central Oregon, that rarely happens because there are only 2 limited area mosquito districts here. After the mosquitoes transform from larvae to adults, the females begin searching for a blood meal, which they need for egg production. Mosquitoes can fly great distances searching for food—sometimes miles. So, the production source often isn’t close to where people are having mosquito problems.

If you’re experiencing high mosquito numbers there are some things you may be able to do to decrease those numbers:

  • Eliminate all standing water on your property. Dump all those 5-gallon buckets that filled up after the last rain storm and don’t forget the old tires; dump those kid pools that you filled 2 weeks ago; dump and refill animal watering containers– bowls, troughs, etc. weekly.
  • Change your landscape watering cycles. Mosquitoes will rest and congregate in areas with higher moisture levels. The more frequently you water your lawns and bushes, the more mosquitoes you’ll attract.  If you have the lushest, greenest landscape in the neighborhood, you’ll also have the most mosquitoes.
  • Water with less frequent, but much longer cycles which encourages deeper roots, but also lowers the humidity in your yard between watering days. This forces mosquitoes to search for other resting areas.
  • Make sure door and window screens are in good shape and installed. Screens are very effective at keeping mosquitoes outside.
  • Enclose your outside patio with a screen if you want to eat outdoors.
  • Use personal repellents. Personal repellents work well for most situations, and they’re 100% better for the environment than spraying your lawns, bushes etc. with pesticides.
  • Wear long-sleeved shirts and long pants.

Mosquito Control Northwest has over 42 years of experience in mosquito control. Please call us for more information at 541-389-4942.