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FIELD MANUAL  //  KNOW THE THREAT

Know the Enemy

Who she is, when she's out, what she actually does to you — and how to find her staging areas on your own land.

01

Identify the Enemy

Know your enemy.
PARA 1 — INTELLIGENCE BRIEF

West Nile Virus is real, it's here, and it travels on mosquitoes. Most summers it's a few bad bites. Some summers it puts someone in the hospital.

The carrier doesn't breed in clean streams or a healthy pond full of fish. She hunts for still, stagnant, funky water sitting in containers — a forgotten bucket, an old tire, a clogged gutter, a low spot that never drains.

Which means the enemy's staging areas aren't out in some swamp. They're on our own land.

Culex tarsalis mosquito — the primary West Nile carrier in South Dakota
TARGET — IDENTIFIED

Culex tarsalis

The primary West Nile carrier across the Northern Plains.

A medium brown mosquito, active mostly at dusk and after dark. South Dakota sees some of the highest West Nile rates in the country — and this is the mosquito doing most of the work.

  • White band around the middle of the proboscis
  • White bands on the legs — the "tarsalis" tell
  • Lays floating egg-rafts on the surface of still, foul water
  • WEAKNESS: she'll raft up in your trap as readily as a roadside puddle
PARA 1A — WHAT TO LOOK FOR IN THE WATER
A mosquito egg raft floating on the surface of still, foul standing water
EGG RAFT — dozens of eggs glued together, floating flat on the surface. This is what she leaves within a day of finding your water.
Mosquito larvae, sometimes called wigglers, hanging just under the surface of standing water
LARVAE ("WIGGLERS") — hatch within days, hang just under the surface to breathe. This is the stage a Bti dunk kills.
02

When She's Active

Time your defense.
PARA 1B — WHEN THE ENEMY IS ACTIVE
Campaign Season — Typical WNV Risk by Month
RELATIVE RISK // SOUTH DAKOTA & NORTHERN PLAINS
PEAK THREAT YOU ARE HERE ▸ MID-JULY · CLIMBING FAST FIRST FROST = ENDGAME APRMAYJUN JULAUGSEP OCTNOV HIGH LOW
SOURCE: CDC & SD surveillance — WNV cases climb through July, peak late Aug–Sept, and end at the first hard frost. Get set up now, before the peak.

Translation: the fight runs from spring thaw to the first hard frost, and the smart move is to be set up before August. Start when the snow's gone, not when you're already getting bit.

03

The Virus, Plain Terms

Why this matters.
PARA 1C — THE THREAT IN DETAIL
WEST NILE VIRUS — PLAIN TERMS

What it is & why it matters here

West Nile is the most common mosquito-borne disease in the Lower 48. You get it from the bite of an infected mosquito — you can't catch it from another person.

Most people who get infected (about 4 in 5) never feel a thing. Around 1 in 5 get flu-like illness — fever, headache, body aches. But roughly 1 in 150 develop serious illness that attacks the brain and spinal cord, which can mean hospitalization, lasting damage, or death. There is no vaccine and no cure — only supportive care. Prevention is the whole game.

And South Dakota is a hot spot. The state has among the highest rates of the severe, brain-and-spine form in the country, with more than 2,800 human cases and 50-plus deaths since 2002. The carrier is the same Culex tarsalis from the ID card above — and this isn't theoretical: human cases have shown up right here in Spink County.

The part that matters for us: the CDC and the SD Department of Health both name the same two defenses — get rid of standing water, and support community mosquito control. That's not our opinion. That's this operation.

04

Recon Your Land

Find the water first.
PARA 1D — RECON YOUR LAND

FIND THE WATER FIRST

Walk the place after a rain. Mosquitoes need only a bottle-cap of standing water for a week. Check:

  • Clogged gutters & downspouts
  • Old tires
  • Buckets, cans, jars
  • Tarps & their folds
  • Flowerpot saucers
  • Water/feed troughs
  • Wheelbarrows & equipment
  • Tire ruts & low spots
  • Kids' toys & pools
  • Birdbaths & pet dishes
  • Boats, tarp-covered gear
  • Plugged culverts

Once you know where the water is, head to Build Plans to decide whether to drain it or trap it.

05

Official Sources

Read more.
PARA 1E — READ MORE