Bids, basis, rain, drought, rent and land value for your place, each with its source and date. Then the farm reference tables: corn N rates, P and K by soil test, manure, crop stages, pest thresholds and conversions.
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Fast Facts: farm reference tables
How much N to put on corn at posted prices, then P and K by soil test, manure, lime, crop stages, pest thresholds and conversions.
Updated Oct 22, 2026; tables checked Oct 16, 2026 · rates from UW Extension A2809 (Wisconsin) unless a table names another source · Sources
Corn N rate at posted prices
-lb N/ac
Loading posted N and corn prices…
$/lb N -N:corn -A2809 column -
Rates from UW A2809 Table 6.1 (Mar 2026 edition), Wisconsin trials, starter included. Subtract manure and second-year alfalfa credits; after corn or a forage legume, also first-year legume credits. Outside Wisconsin, run the same prices in Iowa State's Corn N Rate Calculator, which several Corn Belt states use for their own rates. Full table and credits →
Fall anhydrous: wait until 4-inch soil stays under 50°F. Soil temps near you.
Corn
-
CBOT, delayed
Soybeans
-
CBOT, delayed
Wheat
-
CBOT, delayed
Fertilizer PricesLoading…
Loading prices…
Corn N Rates by Soil and Price Ratio (A2809 Table 6.1)
Total lb N/ac, starter included. The big number is the rate with the most return to N (MRTN, the maximum return to nitrogen); under it, every rate within $1/ac of that return. N:corn ratio = $ per lb of N ÷ $ per bu of corn. The column for the prices in the box at the top is marked.
Which end of the range (A2809): Upper end: more than half the soil covered by residue, or all N from manure. Low end: over 10% organic matter, or N left from last year. Or take the high end less the N a spring soil nitrate test (PPNT) finds. High end: any soil under 2% organic matter. Middle to low: corn after small grains, and sands with 2 to 9.9% organic matter.
Soil Type & Previous Crop
N:Corn Price Ratio
0.05
0.10
0.15
0.20
Loamy: High Yield Potential
Corn, forage legumes, legume veg, green manures
190170–210
165155–180
150140–160
135125–150
Soybean, small grains
140125–160
120105–130
10595–115
9080–105
Loamy: Medium Yield Potential
Corn, forage legumes, legume veg, green manures
145130–160
125115–140
115105–125
10595–110
Soybean, small grains
130110–150
10085–120
8570–95
7060–80
Sands / Loamy Sands: Irrigated
All crops
215200–230
200185–210
185175–195
175165–185
Sands / Loamy Sands: Non-Irrigated
All crops
140130–150
130120–140
120110–130
110100–120
Legume N Credits
Alfalfa: 1st Year (lb N/ac)
Stand Quality
Fine/Med >8"
Fine/Med <8"
Sandy >8"
Sandy <8"
Good, 4+ plants/ft²
190
150
140
100
Fair, 1.5–4 plants/ft²
160
120
110
70
Poor, <1.5 plants/ft²
130
90
80
40
Red clover and birdsfoot trefoil: 80% of the alfalfa credit for a like stand. Second year after a good or fair stand: 50 lb N/ac on medium and fine soils, none on sands. A2809 Table 9.4.
Green Manure and Field Crop Credits
Alfalfa green manure, over 6"60–100 lb N/ac
Red clover green manure, over 6"50–80 lb N/ac
Sweet clover green manure, over 6"80–120 lb N/ac
Any green manure, under 6"40 lb N/ac
Soybean, pea, snap, lima or dry bean, to crops other than corn or wheat20 lb N/ac
Green manures: upper end for spring seedings plowed down the next spring, lower end for fall seedings (Table 9.5). No soybean credit for corn or wheat: the corn-after-soybean rows above already count it. No field-crop legume credit on sands (Table 9.6).
Common Fertilizer Products: % Nutrient Content
Product
% N
% P₂O₅
% K₂O
Other
lbs/gal
Nitrogen Sources
Anhydrous Ammonia (AA)
82
0
0
n/a
n/a
Urea
46
0
0
n/a
n/a
UAN 32%
32
0
0
n/a
11.1
UAN 28%
28
0
0
n/a
10.6
Ammonium Sulfate (AMS)
21
0
0
24% S
n/a
Ammonium Nitrate
34
0
0
n/a
n/a
Phosphorus Sources
DAP
18
46
0
n/a
n/a
MAP
11
52
0
n/a
n/a
MAP + Sulfur (12-40-0-10S)
12
40
0
10% S
n/a
Triple Superphosphate (TSP)
0
46
0
n/a
n/a
10-34-0 liquid
10
34
0
n/a
11.6
Potassium Sources
MOP (Muriate of Potash)
0
0
60–62
n/a
n/a
SOP (Potassium Sulfate)
0
0
50
18% S
n/a
K-Mag (0-0-22)
0
0
22
22% S, 10.8% Mg
n/a
9-18-9 starter liquid
9
18
9
n/a
11.1
K-Mag: 22% K₂O, 22% S and 10.8% Mg are the guaranteed minimums on the maker's 2025 K-Mag Granular data sheet (revised Jan 2025).
Your cost per acre. The N, P and K rates come from the N box at the top and the corn P and K by soil test, priced at the posted prices; type over any box. Seed, chemical, rent and other are yours to fill in.
Corn: Cost Per Acre
Nitrogen: from the N box
lb N/ac ×$/lb N =-
Phosphate (P₂O₅): MAP or DAP, its N credited
lb/ac ×$/lb =-
Potash (K₂O): MOP
lb/ac ×$/lb =-
Seed
$/ac-
Herbicide / Chemical
$/ac-
Land Rent
$/ac-
Other (machinery, drying, overhead)
$/ac-
Total Cost Per Acre-
Take your cost total to the full break-even tool →
The Break-Even Calculator adds a what-if sensitivity table, profit gauge, and printable report.
Enter your soil tests. Get the P₂O₅ and K₂O rate from UW Extension A2809 (Wisconsin): soil test categories from Tables 7.1 and 7.2, rates from Table 7.4. P is the Bray P1 test. Other states set their own categories, so check yours.
Soil Test → Recommendation Calculator
P Category
-
K Category
-
Apply P₂O₅ (lb/ac)
-
Apply K₂O (lb/ac)
-
P₂O₅ Cost
-
K₂O Cost
-
Total P+K $/ac
-
Priced from the MAP and potash $/lb in the Economics tab
Soil Test Categories (ppm), UW A2809 Tables 7.1 and 7.2
P is Bray P1 and K is soil test K, both in ppm. The highest-demand crop in the rotation sets the categories. A corn and soybean field that is irrigated uses level 2. Loamy means medium and fine-textured soils; sandy means sands and loamy sands. P has no Very High class.
Demand level and soil
Test
V.Low
Low
Opt
High
V.High
Ex.High
Level 1: corn grain, soybean
Loamy
P
<10
10–15
16–20
21–30
n/a
>30
Loamy
K
<70
70–100
101–130
131–160
161–190
>190
Sandy, organic
P
<12
12–22
23–32
33–42
n/a
>42
Sandy, organic
K
<45
45–65
66–90
91–130
n/a
>130
Level 2: alfalfa, corn silage, wheat
Loamy
P
<12
12–17
18–25
26–35
n/a
>35
Loamy
K
<90
90–110
111–140
141–170
171–240
>240
Sandy, organic
P
<18
18–25
26–37
38–55
n/a
>55
Sandy, organic
K
<50
50–80
81–120
121–160
161–200
>200
How A2809 sets the rate: Optimum is what the crop removes. Low and Very Low add build-up over 4 to 8 years. High is half the optimum rate, Very High (K only) a quarter, and Excessively High none. Rates are the total, starter included.
Corn Grain P₂O₅ & K₂O Rates (A2809 Table 7.4)
Corn Yield Goal (bu/ac)
Soil Test Level
V.Low
Low
Opt
High
V.High
Ex.High
Phosphate (P₂O₅) lb/ac
71–90
70
60
30
15
n/a
0
91–110
80
70
40
20
n/a
0
111–130
85
75
45
25
n/a
0
131–150
95
85
55
30
n/a
0
151–170
100
90
60
30
n/a
0
171–190
110
100
70
35
n/a
0
191–210
115
105
75
40
n/a
0
211–230
125
115
85
45
n/a
0
231–250
130
120
90
45
n/a
0
251–270
140
130
100
50
n/a
0
Potash (K₂O) lb/ac
71–90
70
55
25
15
5
0
91–110
75
60
30
15
10
0
111–130
80
65
35
20
10
0
131–150
85
70
40
20
10
0
151–170
90
75
45
25
10
0
171–190
95
80
50
25
15
0
191–210
105
90
60
30
15
0
211–230
110
95
65
35
15
0
231–250
115
100
70
35
20
0
251–270
120
105
75
40
20
0
Soybean P₂O₅ & K₂O Rates (A2809 Table 7.4)
Yield Goal (bu/ac)
Soil Test Level
V.Low
Low
Opt
High
V.High
Ex.High
Phosphate (P₂O₅) lb/ac
15–25
55
45
15
10
n/a
0
26–35
65
55
25
15
n/a
0
36–45
70
60
30
15
n/a
0
46–55
80
70
40
20
n/a
0
56–65
90
80
50
25
n/a
0
66–75
95
85
55
30
n/a
0
76–85
105
95
65
35
n/a
0
86–95
110
100
70
35
n/a
0
96–105
120
110
80
40
n/a
0
Potash (K₂O) lb/ac
15–25
75
60
30
15
10
0
26–35
85
70
40
20
10
0
36–45
100
85
55
30
15
0
46–55
115
100
70
35
20
0
56–65
130
115
85
45
20
0
66–75
145
130
100
50
25
0
76–85
155
140
110
55
30
0
86–95
170
155
125
65
30
0
96–105
185
170
140
70
35
0
Corn Silage P₂O₅ & K₂O Rates (A2809 Table 7.4)
Silage goal, ton/ac at 65% moisture
Soil Test Level
V.Low
Low
Opt
High
V.High
Ex.High
Phosphate (P₂O₅) lb/ac
10–15
85
75
45
25
n/a
0
15.1–20
105
95
65
35
n/a
0
20.1–25
120
110
80
40
n/a
0
25.1–30
140
130
100
50
n/a
0
30.1–35
155
145
115
60
n/a
0
35.1–40
175
165
135
70
n/a
0
Potash (K₂O) lb/ac
10–15
160
145
105
55
25
0
15.1–20
200
185
145
75
35
0
20.1–25
240
225
185
95
45
0
25.1–30
285
270
230
115
60
0
30.1–35
325
310
270
135
70
0
35.1–40
365
350
310
155
80
0
Alfalfa P₂O₅ & K₂O Rates, Established Stand (A2809 Table 7.4)
Alfalfa Yield Goal (ton/ac dry matter)
Soil Test Level
V.Low
Low
Opt
High
V.High
Ex.High
Phosphate (P₂O₅) lb/ac
2.6–3.5
80
70
40
20
n/a
0
3.6–4.5
90
80
50
25
n/a
0
4.6–5.5
105
95
65
35
n/a
0
5.6–6.5
120
110
80
40
n/a
0
6.6–7.5
130
120
90
45
n/a
0
7.6–8.5
145
135
105
55
n/a
0
8.6–9.5
155
145
115
60
n/a
0
Potash (K₂O) lb/ac
2.6–3.5
235
220
180
90
45
0
3.6–4.5
295
280
240
120
60
0
4.6–5.5
355
340
300
150
75
0
5.6–6.5
415
400
360
180
90
0
6.6–7.5
475
460
420
210
105
0
7.6–8.5
535
520
480
240
120
0
8.6–9.5
595
580
540
270
135
0
Seeding-year alfalfa (1.5–2.5 ton): 65, 55, 25, 15 and 0 lb P₂O₅; 160, 145, 105, 55, 25 and 0 lb K₂O, Very Low to Excessively High. Keeping a stand more than 3 years, A2809 raises topdressed K₂O by 20%. Silage and alfalfa take the whole plant, so retest every 2 years. Source: UW Extension A2809 (Laboski and Peters).
Olsen P users: A2809 categories are for the Bray P1 test. A2809 gives no Olsen conversion, so ask your lab for Bray P1 or use your state's Olsen guide.
Nutrients Removed at Harvest
Crop & Component
Yield Unit
lb P₂O₅
lb K₂O
Corn
Corn, Grain
per bu (56 lb @ 15.5%)
0.38
0.29
Corn, Silage
per ton (65% moisture)
3.6
8.3
Corn Stover
per ton DM
4.6
32
Soybean
Soybean, Grain
per bu (60 lb @ 13%)
0.80
1.4
Soybean Straw
per ton DM
5.4
19
Alfalfa & Forage
Alfalfa / Red Clover
per ton DM
13
60
Small Grain Silage
per ton DM
11
44
Small Grains
Wheat, Grain
per bu (60 lb @ 13.5%)
0.50
0.35
Barley, Grain
per bu (48 lb @ 14.5%)
0.40
0.35
Oats, Grain
per bu (32 lb @ 14%)
0.29
0.19
A2809 Table 4.2, lb per unit of yield at the moisture shown. Nutrient removal value prices what a field hauls off.
Nutrient Removal Calculator
Field Nutrient Export Estimator
P₂O₅ /ac
-
K₂O /ac
-
Total P₂O₅
-
Total K₂O
-
Plant Population by Row Width
Row Width
20"
28"
30"
32"
36"
38"
40"
Row length for 1/1000 ac
26'2"
18'8"
17'5"
16'4"
14'6"
13'9"
13'1"
Formula: Count plants in that row length × 1,000 = plants/acre. Count at least 3 rows.
Bu/Acre Calculator: Shelled Corn
Corn Yield Calculator
Bu @ 15.5%
-
Bu / Acre
-
Total and Available Nutrient Content by Manure Type
Total N, P₂O₅ and K₂O in the manure, then what a crop can use the first year: N by time to incorporation [second-year N in brackets], P₂O₅ and K₂O. Solid in lb/ton, liquid in lb/1,000 gal. Book values from UW Extension A2809 (R-11-2012), Tables 9.2 and 9.3; the first year counts 80% of the P and K and 25 to 65% of the N (Table 9.1). Farm manure varies a lot, so a manure test beats this table.
Work it in fast. Manure left on the surface loses N to the air, most in warm, windy weather. The columns show how much.
Manure type
Total in the manure
N the crop can use, 1st yr [2nd yr]
P and K, 1st yr
N
P₂O₅
K₂O
Not in 3 days
1 hr–3 days
Within 1 hr
P₂O₅
K₂O
Dairy
Solid, over 20% dry matter (lb/ton)
9
4
7
2 [1]
3 [1]
3 [1]
3
6
Solid, 11 to 20% dry matter (lb/ton)
8
4
6
2 [1]
2 [1]
3 [1]
3
5
Liquid, 4 to 11% dry matter (lb/1,000 gal)
24
8
21
7 [2]
10 [2]
12 [2]
6
17
Liquid, under 4% dry matter (lb/1,000 gal)
14
4
14
4 [1]
6 [1]
7 [1]
3
11
Beef
Solid (lb/ton)
13
8
12
3 [1]
4 [1]
5 [1]
6
10
Liquid (lb/1,000 gal)
16
7
15
5 [2]
6 [2]
8 [2]
6
12
Hog
Solid (lb/ton)
18
13
10
7 [2]
9 [2]
12 [2]
10
8
Liquid, finishing, indoor pit (lb/1,000 gal)
43
18
28
17 [4]
22 [4]
28 [4]
14
22
Liquid, finishing, outdoor storage (lb/1,000 gal)
18
7
10
7 [2]
9 [2]
12 [2]
6
8
Poultry
Chicken, solid (lb/ton)
49
44
33
24 [5]
27 [5]
29 [5]
35
26
Turkey, solid (lb/ton)
51
44
31
26 [5]
28 [5]
31 [5]
35
25
Horse
Solid (lb/ton)
10
6
8
2 [1]
3 [1]
4 [1]
5
6
What is it worth in dollars? More on the manure value page, with a calculator for your own test.
Manure Value Calculator
The N, P₂O₅ and K₂O in the manure at dated posted prices: an acre, per 1,000 gal or ton, and for the field. All the pounds count, with the first-year part under the total; type your own test and it uses your pounds. The same calculator as on the manure value page.
The calculator needs JavaScript.
Application Rate Calculator
Application Rate Calculator
Total Applied
-
Application Rate
-
Soil pH Targets
Target pH by Crop (mineral soils)
Alfalfa6.8
Barley6.6
Red clover, soybean6.3
Corn (grain or silage), wheat6.0
Oats5.8
Organic soils: 5.6 for these crops but alfalfa. Lime for the highest target in the next 4 years. A2809 Table 4.2 and Chapter 5.
Liming Rules (A2809)
Lime when water pH is0.2+ below target
Most lime at once12 ton/ac
Most lime at once, potatoes8 ton/ac
Least worth spreading2 ton/ac of 60–69
Sands under 1% OM, need under 1.5 t1 ton/ac
Before liming again2–3 years, then retest
A big pH change ahead of alfalfa: A2809 says it may be wise to wait a year to seed.
Lime Requirement Calculator
Lime Rate (UW A2809 Table 5.1: water pH and buffer pH)
60–69 Lime (A2809 base)
-
Your Lime, ton/ac
-
Guidance
-
Est. Cost/Acre
-
How it works: A2809 Table 5.1 gives tons of 60–69 NI lime from your water pH and buffer pH (the Sikora buffer pH, the lime-need number on a Wisconsin soil report). Your lime = that × 65 ÷ NI (use the middle of the grade, 85 for 80–89). Lime only when water pH is more than 0.2 below target. Minimum 2 ton of 60–69 lime (1.5 of 80–89); never over 12 ton. NI is not the same as CCE: use the NI on the lime label or ask the quarry. Example: buffer 6.5, water 6.0, target 6.8 is 195 − 28.4 × 6.5 + 0.144 × 6.0 = 11.3 ton of 60–69 lime, or 8.5 ton of 80–89. Cost uses the price you type; lime prices swing with haul distance. Source: UW Extension A2809, Chapter 5. Other states use other buffers and formulas; use your state’s guide outside Wisconsin.
Micronutrient Soil Tests (A2809 Table 8.4)
Nutrient, soil
V.Low
Low
Opt
High
Ex.High
Boron, sandy
0–0.2
0.3–0.4
0.5–1.0
1.1–2.5
>2.5
Boron, loamy
0–0.3
0.4–0.8
0.9–1.5
1.6–3.0
>3.0
Boron, organic
0–0.5
0.6–1.0
1.1–2.0
2.1–4.0
>4.0
Zinc, all soils
0–1.5
1.6–3.0
3.1–20
20.1–40
>40
Manganese, sandy or loamy
n/a
0–10
11–20
>20
n/a
Who needs it (Table 8.3)
Corn grainZn high · S medium
Corn silageZn high · S high
Soybean grainMn high · Zn medium
Alfalfa, establishedB high · S high
Wheat, oatsMn high
How much (A2809 Ch. 8)
Zinc, low test, banded2–4 lb/ac
Zinc, low test, broadcast4–8 lb/ac
Manganese, low test, high need5 lb/ac in the row
Boron, low test, high need2 lb/ac (3 if very low)
Sulfur, corn and small grains10–25 lb/ac
Sulfur, forage legumes topdressed15–25 lb/ac
Zinc rates are for crops with a medium or high need; confirm that need with a plant analysis first. Manganese is unlikely to be short below pH 6.8; broadcast Mn does not work. Over 6% organic matter, Mn goes by pH, not the test.
Tissue tests: A2809 prints no corn or soybean tissue table, so none is printed here. Use the sufficiency ranges your lab prints with the result.
Corn Growth Stages: Interactive GDU Timeline
Tap any stage for its GDUs, what the plant is doing and what to watch. GDUs from planting (highs capped at 86°F, lows floored at 50°F), for a 2,700-GDU hybrid (Purdue NCH-40), the same table as the GDU calculator.
Select a stage above to view details
Soybean Growth Stages: Interactive Timeline
GDUs from planting. Soybean stages follow day length as much as heat, so read these GDU marks as rough. Tap any stage.
Select a stage above to view details
GDU Calculator
Daily GDU (Base 50°F)
Today’s GDUs
-
New Total
-
Corn Stage
-
Soybean Stage
-
GDU calculator: GDUs from your planting date on real weather. Spray conditions: wind, temperature, humidity and inversion risk where you are.
Economic Thresholds: Key Insects
Pest
Treat when
When
Corn
Black Cutworm
5% or more of plants show damage and larvae are 6th instar or smallerSpot or border-row treatment (UW L023).
Seedling corn
Armyworm
1 armyworm per plant on 75% of plants, or 2 per plant on 25%Spot treatment (UW L023).
June–July
Corn Rootworm (adult)
5 or more beetles per plant in the first week of pollen shed, or silks clipped to 1/2" on 25–50% of plantsNo yield hit once silks are brown (SDSU). Iowa State: 5+ beetles per ear with silks under 1", up to 15 per ear with good moisture. The 0.75 beetles per plant number is for next year: counted mid-August to mid-September, it says corn on corn needs rootworm protection (UW L023). It is not a spray trigger.
VT–R1
Japanese Beetle
3+ beetles/ear, silks clipped under 1", pollination not doneIowa State. Beetles keep moving in; scout until pollination is done.
VT–R1
Soybean
Soybean Aphid
250 aphids/plant average, on more than 80% of plants, increasingScout weekly from mid to late June until R6.5. Average plants from across the field, not the edges. No threshold is set for R6 (UMN).
Through R5
Western bean cutworm, European corn borer, bean leaf beetle, leaf feeders on soybeans and spider mites: use your state's current field crop pest guide (Wisconsin's is A3646).
The main soil residual for waterhemp. Resistance confirmed in Illinois populations in 2019, the first in a broadleaf weed; still rare.
Group 27
HPPD inhibitor
Callisto, Laudis, Impact, Balance
Corn
Strong on waterhemp; some populations now resist it (see below).
Waterhemp management priority across the Corn Belt: Waterhemp has confirmed resistance to seven site-of-action groups: 2, 4, 5, 9, 14, 15 and 27. Groups 2 and 9 are widespread; resistance to 4, 15 and 27 is in some populations, and fields with five- and six-way resistant waterhemp are on record. That makes it the highest resistance-management priority in most corn and soybean regions. Use 3+ effective MOA programs with a soil residual, and do not rely on post-only programs. Sources: Ohio State Extension fact sheet ANR-78 (a Missouri population resistant to Groups 2, 4, 5, 9, 14 and 27); University of Illinois, Group 15 resistance in Champaign and McLean county waterhemp (DTN, Apr 2019); the International Herbicide-Resistant Weed Database lists each case.
Corn, soybean and wheat acres, yield and production for each state, from USDA NASS, live on one page per state. Pick a state for its link. U.S. totals and every state side by side: Yield by state.
It depends on your soil, the last crop and the N:corn price ratio: the price of a pound of N divided by the price of a bushel of corn. UW Extension A2809 (Mar 2026 web edition), from Wisconsin trials, gives corn after soybeans on high-yield loamy soil 140 lb N at a 0.05 ratio, 120 at 0.10, 105 at 0.15 and 90 at 0.20. Corn after corn on the same soil gets 190, 165, 150 and 135. Subtract manure and legume credits. The N box on the Reference tables tab works out the ratio from posted N and corn prices. Outside Wisconsin, use your state's MRTN rates.
What is my manure worth in fertilizer value?
Multiply the total N, P2O5 and K2O in each ton or 1,000 gallons by what those nutrients cost as urea, MAP and potash. That is the value of all of it. A crop can use 80% of the P2O5 and K2O and 25 to 65% of the N the first year, by UW Extension A2809. The Manure tab has the pounds by manure type and a calculator at dated posted prices. The manure value page at agsist.com/manure-value prices every manure type, an acre and for a whole field.
What is the economic threshold for soybean aphid?
250 aphids per plant on average, aphids on more than 80% of plants, and the population rising. That threshold runs through R5. University of Minnesota Extension sets no threshold for R6.
How do I calculate growing degree units for corn?
GDU (base 50°F) = [(daily max temp, capped at 86°F) + (daily min temp, floor at 50°F)] / 2 - 50. Accumulate daily from planting.
When is it worth spraying Japanese beetles on corn silks?
Iowa State says spray only when all three are true: three or more beetles per ear, silks clipped to less than an inch, and pollination not done yet. Feeding is worse at the field edge, so look across the whole field before you make the call.
When do I start and stop scouting beans for aphids?
Minnesota Extension says start in mid to late June and keep going until R6.5, when pods and leaves begin to yellow, whatever the calendar says. Once a field has aphids, check it every week, because they build fast.
Sources and terms
Every number on this page comes from one of these, read on the date shown. Prices are dated where they appear. Found a wrong number? Email sig@agsist.com and I will fix it.
Prices: fertilizer from co-op posted cash prices (fertilizer prices, dated); corn, soybean and wheat futures are delayed CBOT closes; state corn basis is the median of AGSIST elevator bids this week (cash bids).
Iowa State Corn N Rate Calculator for N rates outside Wisconsin. USDA NASS for state production. This product uses the NASS API but is not endorsed or certified by NASS.
Sig Lindquist, CCA, Chetek, Wisconsin. No sponsor sets any number here.