John Deere See & Spray: independent university trials cut post-emergence herbicide 43–62%

The problem

Broadcast spraying applies post-emergence herbicide across an entire field regardless of where weeds actually are. That wastes product, raises grower cost, and — with herbicide- resistant weeds like Palmer amaranth spreading — keeps chemical pressure high across ground that has no weeds on it at all.

What was built

John Deere’s See & Spray is a computer-vision targeted-spraying system. Cameras and on-board processors on the sprayer boom detect green weeds against soil and residue in real time and fire only the nozzles over a weed, instead of broadcasting herbicide across the whole field. The version measured in the Iowa State study is the See & Spray Ultimate.

What makes this story verifiable is who measured it: not John Deere’s marketing, but independent university weed-science programs.

The outcome

Every figure below is quoted verbatim from an independent source fetched this session; each number is attributed to its own source and none are merged.

• Peer-reviewed (University of Arkansas), Weed Technology 2024 — Avent, Norsworthy et al., two years at Keiser, AR and Greenville, MS: “On average, targeted sprays saved a range of 28.4% to 62.4% on postemergence herbicides.”
• University of Arkansas 3-year trial (March 2025) — “43-59 percent reduction in herbicide use compared to broadcast applications.” Modeled Arkansas grower savings of 13–80%, or $1.6 million to $48 million per year on post-emergence herbicide expenditures.
• Iowa State University field-scale study (Aug 2024) — five soybean fields, 415 acres: “Average product savings across all fields was 76% and had an economic savings of nearly $6,500 ($15.7/ac) from reduced herbicide use” (per-field range 43.9%–90.6%).

The honest tradeoff (shown, not merged away)

The same University of Arkansas trial found a real, setting-dependent risk. At a low sensitivity setting — where only larger weeds get sprayed to maximize short-term savings — missed small Palmer amaranth let the pigweed population increase 280% each year, which “could result in accelerated herbicide resistance or additional in-season applications, costing Arkansas producers upwards of $60 million per year.” Lead researcher Jason Norsworthy, Distinguished Professor of weed science, is on record: “All of my data would indicate that using the high-sensitivity setting is best in most scenarios” — at which control is comparable to broadcast and herbicide savings stay substantial.

Path to green

The headline already rests on independent academic measurement — a peer-reviewed paper plus a second, independent university field study — which is a stronger footing than a single-vendor or single-client attestation. Green requires only a human confirmation step:

1. Re-archive all four sources to web.archive.org (the Internet Archive was “Temporarily Offline” this session; local sources/ copies are saved in the meantime).
2. A recorded confirmation from Jason Norsworthy / Tristen Avent (University of Arkansas) or Doug Houser / Matt Darr (Iowa State) that the figures, measurement windows, and sensitivity settings are represented correctly.