Ag Drone Spraying for Pierce County, Wisconsin Dairy and Grain Farms

Ag drone spray rates in Pierce County, WI

Ag drone spraying in Pierce County, WI is quoted per acre for one pass, application only. The county's 1,150 farms average 200 acres and grow mostly corn, soybeans and dairy forage. Rates are set for that mix and for the hilly fields between Ellsworth, Plum City and Lake Pepin.

Service	Typical rate	Notes
Corn and soybean herbicide	from $14/acre	Post-emerge passes, 2–3 gallons per acre
Corn and soybean fungicide	from $15/acre	Tassel and R3 timings, no wheel tracks
Alfalfa insecticide	from $14/acre	Weevil and leafhopper, between cuttings
Oat and wheat fungicide	from $15/acre	Flag leaf to heading
Cover crop seeding	from $16/acre	Into standing crops or after silage

Product is billed separately, or the grower supplies it. Wisconsin drone rates run about $11–22 per acre, with $16 typical. For comparison, the UW custom rate survey puts ground fungicide at $12.17 per acre on average. The quote moves with water volume, canopy height, field shape and slope, and obstacles such as tree lines and power lines. Grouping several fields into one trip lowers it. The minimum charge is $275 per visit.

Pierce County farms in the 2022 Census

Measure	Pierce County, WI
Farms / land in farms	1,150 farms / 229,659 acres
Market value of sales	$190.5M, 36th in Wisconsin, up 28% since 2017
Crop vs livestock sales	53% / 47%
Grains and oilseeds	$90.3M, 21st in Wisconsin
Milk	$64.5M
Corn for grain / soybeans	62,968 / 41,586 acres
Hay and haylage / corn silage	30,934 / 6,750 acres
Cattle and calves	40,211 head

Dairy still shapes the farmland. The Ellsworth Cooperative Creamery, founded in 1910, buys milk from more than 250 patron farm families, and Ellsworth has been Wisconsin's official Cheese Curd Capital since 1983. In practice, almost every operation here grows forage next to its corn and soybeans, and the spray calendar has to work around hay cuttings.

Ag drone spray jobs by crop in Pierce County

• Corn: post-emerge herbicide, then a fungicide at tassel when disease pressure justifies it. Tall corn is where a drone saves the most, because high-clearance rigs are scarce in the busy weeks.
• Soybeans: herbicide follow-ups for resistant waterhemp, and an R3 fungicide or insecticide when aphids pass threshold.
• Alfalfa: insecticide for alfalfa weevil and potato leafhopper, timed to regrowth and the next cutting date.
• Oats and wheat: flag leaf to heading fungicide on the small-grain acres that rotate with alfalfa.
• Cover crops: cereal rye or oats flown into standing corn and soybeans, or onto the 6,750 acres of silage ground right after chopping.

Why drones fit hilly Pierce County fields

Fields east of the Mississippi bluffs climb in and out of stream valleys. Many are farmed in contour strips, with corn, alfalfa and small grain side by side. A ground sprayer on those slopes is slow, risks rollover on side-hills, and leaves wheel tracks in the alfalfa strip next to the corn. A spray drone follows the terrain at a set height and can switch on and off strip by strip from a mapped boundary. Compared with an airplane, it works at 8–15 feet above the canopy, not at airplane height, which matters next to trout streams and farmsteads.

Alfalfa weevil and potato leafhopper thresholds

UW–Madison Integrated Pest and Crop Management sets the trigger for alfalfa weevil at more than 40% of stem tips showing feeding. Peak damage usually comes at 600–800 growing degree days (base 48°F), so the first cutting is often the better control than a spray. Potato leafhopper is judged per sweep, using a 15-inch net and 100 sweeps, and the threshold rises with plant height:

Alfalfa height	Leafhoppers per sweep
3 inches	0.2
6 inches	0.5
8–11 inches	1.0
12 inches and taller	2.0

Leafhopper populations fade by mid-August. A drone pass on regrowth after first or second cutting protects the next crop without tracking the stand.

Soybean aphid, waterhemp and the 2026 dicamba rules

UW sets the soybean aphid threshold at 250 aphids per plant on average across 20–30 plants, with numbers still rising. Below that, a spray usually costs more than it saves.

Waterhemp is the harder problem. Glyphosate-resistant waterhemp has been reported in Pierce County, and PPO plus glyphosate multiple resistance has been confirmed elsewhere in Wisconsin. Layered residuals and a second effective mode of action in the post pass are now standard.

Over-the-top dicamba was re-registered for 2026. Pierce County lies south of I-94, so the cutoff is June 12. Labels prohibit applications above 85°F, require a 240-foot downwind buffer, and do not allow aerial application. Drones cannot apply OTT dicamba, so a drone program for soybeans relies on glufosinate and other labeled post products.

Tar spot and corn fungicide timing

Tar spot has been established in Wisconsin since the late 2010s, and western counties scout for it from July. A fungicide decision is usually made between tassel and early grain fill, based on lesions on the ear leaf, the hybrid's rating, and the weather outlook. At that stage the corn is over 8 feet tall, and a drone treats it without driving down rows.

Class I trout streams and Lake Pepin

Pierce County drains to the St. Croix and Mississippi through some of western Wisconsin's best trout water:

• Kinnickinnic River: a 22-mile Class I trout stream, an Outstanding Resource Water above Highway 35. River Falls is removing its dams, with the Powell Dam targeted for 2026.
• Rush River: almost 50 miles long, entering Lake Pepin about a mile west of Maiden Rock.
• Trimbelle River: a Class II brown trout stream meeting the Mississippi about 5 miles west of Bay City.

Fields along these valleys need label setbacks, low drift, and wind direction away from the water. Groundwater matters too. In county well samples from 1990–2006, 85% met the nitrate standard, which still leaves a share of rural wells above it. Spot treatments and accurate rates help keep herbicide out of shallow aquifers.

Airspace around Red Wing Regional and the Twin Cities

Red Wing Regional Airport sits in Hager City, inside Pierce County, so fields near it need airport coordination. Western Pierce County is close to Twin Cities controlled airspace. Operators check FAA authorizations for every field near Prescott and River Falls before flying.

Wisconsin DATCP licensing for drone applicators

Under DATCP rules, a for-hire drone applicator in Wisconsin needs:

1. FAA credentials: Part 107, a Part 137 agricultural aircraft certificate, and a Section 44807 exemption for drones over 55 pounds.
2. Certification in a base category, such as 1.1 Field and Vegetable Crops, plus category 9.9 Aerial Application.
3. An annual Individual Commercial Applicator License.
4. A Pesticide Business License for the company.

Farmers flying their own drone use a private base category plus category 111.0 Aerial Application if they apply restricted-use products. Wisconsin takes part in FieldWatch, so operators check DriftWatch and BeeCheck for organic fields, specialty crops and apiaries before each job.