Table 1. Cultural operations and fertilizer applications.
Date Plot Operation
5/2/83 Both Plant corn with no-till planter.
N2.5 Apply 560 lb/a (627 kg/ha) 13-13-13 fertilizer under corn with no-till planter.
S2.5 Broadcast 560 lb/a (627 kg/ha) 13-13-13 fertilizer.
5/31/83 N2.5 Sidedress 400 lb/a (448 kg/ha) 34-0-0 in 20-in. (50.1-cm) rows with no-till drill.
S2.5 Sidedress 400 lb/a (448 kg/ha) 34-0-0 broadcast after no-till drill (empty).
9/23/83 N2.5 Harvest 80 bu/a (6,270 kg/ha) corn and shred stalks.
S2.5 Harvest 89.1 bu/a (6,990 kg/ha) corn and shred stalks.
4/26/84 Both Same as 5/2/83
5/29/84 Both Same as 5/31/83
10/31/84 N2.5 Harvest 47.4 bu/a (3,720 kg/ha) corn and shred stalks.
S2.5 Harvest 47.6 bu/a (3,730 kg/ha) corn and shred stalks.
4/22/85 Both Same as 5/2/83
5/16/85 N2.5 Sidedress 200 lb/a (224 kg/ha) urea (46%) in 20-in.(50.1-cm) rows with no-till drill.
S2.5 Sidedress 200 lb/a (224 kg/ha) urea (46%) broadcast after no-till drill (empty).
9/25/85 N2.5 Harvest 127.9 bu/a (10,030 kg/ha) corn and shred stalks.
S2.5 Harvest 114.5 bu/a (8,980 kg/ha) corn and shred stalks.
Note: Corn yield was computed using a basis of 70 pounds per bushel of ear corn at 15.5 percent moisture.


Table 2. Rainfall, runoff, and soil loss by crop stage.1
Crop
stage2		 Begin
date		 Rain
(mm)		 North 2.5 South 2.5 Adjusted
North 2.5
RO
(mm)		 SL
(t/ha)		 RO
(mm)		 SL
(t/ha)		 RO
(mm)		 SL
(t/ha)
pl/fert 5/2/83 278 98 0.348 92 0.395 122 0.434
pl/fert 4/26/84 285 89 0.303 109 0.381 111 0.378
pl/fert 4/22/85 164 39 0.119 51 0.166 48 0.149
3-yr total   727 225 0.769 252 0.942 282 0.961
sd/fert 5/31/83 219 0 0.002 1 0.002 0 0.003
sd/fert 5/29/84 490 29 0.065 75 0.184 36 0.081
sd/fert 5/16/85 413 43 0.103 54 0.164 54 0.129
3-yr total   1,122 72 0.170 131 0.350 91 0.213
harv 9/23/83 844 134 0.206 157 0.117 167 0.258
harv 10/31/84 495 52 0.092 99 0.173 65 0.115
harv 9/25/85 427 40 0.056 37 0.047 50 0.070
3-yr total   1,766 226 0.354 293 0.336 282 0.443
Average annual   1,205 175 0.431 225 0.543 218 0.539
1 All values are totals or averages of storm amounts.
2 Crop stages: pl/fert is from planting to sidedress; sd/fert is from sidedress to harvest; harv is from harvest to planting.


Table 3. Concentrations of nutrients in runoff and soil loss.1
Begin
date3		 Inserted fertilizer2 Broadcast fertilizer2
NO3-N PO4-P NH4-N TP TN NO3-N PO4-P NH4-N TP TN
  --------mg/l------- --------mg/kg-------- --------mg/L-------- --------mg/kg--------
Plant and apply fertilizer:
5/2/83 0.81 0.35 0.55 1,755 6,781 2.80 0.55 0.91 1,825 5,114
4/26/84 0.98 0.56 1.06 1,693 6,680 2.40 1.96 5.90 2,252 6,371
4/22/85 1.32 0.93 1.56 3,974 8,221 4.35 3.72 12.94 2,623 7,861
3-yr avg 0.97 0.53 0.93 2,074 6,964 2.94 1.80 5.50 2,138 6,107
Range 0.21- 0.25- 0.34- 1,180- 4,482- 0.57- 0.44- 0.53- 1,281- 2,633-
  8.02 3.09 8.09 4,606 27,532 13.92 10.00 33.85 4,353 30,357
Apply sidedress fertilizer:
5/31/83 4.11 0.51 1.74 2,040 11,495 7.39 0.46 1.91 2,259 10,214
5/29/84 1.97 0.26 0.92 1,731 8,456 2.22 0.59 1.20 575 3,025
5/16/85 3.38 0.43 0.92 1,829 7,785 4.67 0.66 1.40 1,602 6,530
3-yr avg 2.81 0.36 0.93 1,794 8,090 3.34 0.62 1.30 1,066 4,712
Range 0.47- 0.07- 0.36- 1,437- 5,891- 0.60- 0.31- 0.21- 196- 855-
  4.91 0.92 4.32 4,084 76,034 8.05 1.95 2.92 3,556 55,394
Harvest and shred stalks:
9/23/83 0.35 0.14 0.30 2,510 9,190 0.17