1 Ag Source

Corn & soybean growers — IA & S. Minnesota

Spray when your field
says so, not a day sooner.

We're a scouting-first partner. Get the honest read on southern rust and tar spot, run your own numbers, and we'll source the fungicide when it pencils out.

2026 Iowa Corn Disease Watch
tracking
Southern rust
(confirmed Jul 21)
4 counties, low
Tar spot
~11 counties
Leaf wetness / dew
Lower than 2025
Best spray window (corn)
VT–R3
Southern rust is in Benton, Mahaska, Muscatine & Louisa counties at low severity. It arrived later than 2025 and drier air is slowing it — but it moves fast once it takes hold. Scout the ear leaf; hybrid susceptibility drives the call. Source: ISU Extension, July 22.

Does it pencil out?

Fungicide ROI calculator

Plug in your own numbers — these are just starting points to edit. The math is yours to keep, whether you buy from us or not.

bu
$
$
$
Break-even yield
5.7 bu/ac
Net return
+$1.20 /ac
Yield response varies a lot and is largest under real disease pressure — university trials show the payoff is inconsistent when disease is low. Scout your field, check the crop risk model, and use this to decide. This is an estimate, not a guarantee.

Free — no obligation

Get on the alert list

A quick text or email from a real person when tar spot risk climbs in your area. No spam, no pressure.

  • County-level tar spot & disease alerts

  • Straight talk on timing — VT–R3, not "spray now"

  • Competitive fungicide pricing when you're ready

1 Ag Source

An independent crop protection broker. We're not tied to one label — we scout the honest read and source the right fungicide at a fair price, shipped to you.

Joel Akers

The ROI calculator is a planning estimate based on the numbers you enter and does not guarantee a yield response or return. Fungicide performance depends on disease pressure, timing, hybrid/variety, and weather. Always scout your own fields and follow the product label.

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