Table 1. Average annual runoff in inches and soil loss in tons per acre from poor and good management for corn on duplicate 0.25-acre contoured plots; data for November 1958 to October 1960a.
	Runoff (in)		Soil loss (t/a)
	Poor mgtb	Good mgtc	Poor mgt	Good mgt
Contoured plots	18.0	13.8	17.8	9.3
Watersheds	12.9	10.3	19.5	14.0

^a Adapted from Doty and Dendy (1962).
^b Poor management included light fertilization and planting rates; corn stalks were
left standing following harvest.
^c Good or improved management included using recommended fertilization and planting rates;
corn stalks were shredded in the fall and left on the soil surface to protect the soil from erosion.

Table 2. Average annual runoff in inches and soil loss in t/a from good and poor management for pasture; 1959-1963a data.
Treat- ment	5% Plots		10% Plots		Watershedb
	Runoff	Soil loss	Runoff	Soil loss	Runoff	Soil loss
Good	9.01	0.15	9.37	0.14
Poor	12.04	0.27	17.90	0.69	15.23	2.32

^aAdapted from Carter et al. (1966a).
^b9.2% average slope.

Table 3. Effects of contouring on soil and water losses; 1962-1968 average annual data from continuous corn on duplicate plots on 5% slopesa.
	Contoured Plots		Up-and-down-hill Plots
	0.022 acreb	0.25 acrec	0.022 acred
Runoff (in)	4.2	13.2	12.7
Soil Loss (t/a)	1.1	4.5	11.0

^aAdapted from McGregor et al. (1969b).
^b13.3-ft row length, 72.6-ft slope length.
^c150-ft row length, 72.6-ft slope length.
^d72.6-ft row length, 72.6-ft slope length.

Table 4. Bermudagrass-corn rotation; 1963-1968 average annual runoff and soil loss data from 0.022 acre plots, 1963-1968a.
	1st year grass	2nd year grass	Corn after grass	Rotation Av
Runoff (in)	12.66	10.45	11.80	11.65
Soil Loss (t/a)	2.20	1.15	5.98	3.10

^aAdapted from McGregor et al. (1969b).

Table 5. Average annual runoff and erosion from continuous corn; 1962-1968 data from duplicate contoured plotsa.
	Slope steepness
	2.5%	5%	10%
Runoff (in)	12.04	14.05	18.21
Soil loss (t/a)	3.39	4.24	7.76

^a Adapted from McGregor et al. (1969b).

Table 6. Annual average runoff and soil loss from duplicate fallow plots on 5% slope, 1963-1968a.
	Soil type
	Loring	Lexington
Runoff (in)	22.7	22.8
Soil loss (t/a)	87.8	71.3

^a Adapted from McGregor et al. (1969b).

Table 7. Average annual rainfall, runoff, and soil loss from a 1.45- acre watershed with a 7% average slope in continuous corna.
	Rainfall	Runoff	Soil loss
	(in)	(in)	(t/a)
Before terracing 10/1/59-9/30/62)	54.22	14.67	11.92
After terracing 10/1/63-9/39/66	49.23	16.88	5.96

^a Adapted from Carter et al. (1966b).

Table 8. Three-year (1970-72) average runoff and soil loss from doublecrop soybeans and wheat (no-till) on duplicate plots and small watershedsa.
	Runoff	Soil loss
	(%)	(t/a)
Up-and-down-hill planted plots, 0.022 acre	23	0.8
Up-and-down-hill planted watershed, 3.88 acres	40	2.9
Contour planted watershed, 1.61 acres	27	1.6

^a Adapted from McGregor et al. (1975).

Table 9. Early erosion evaluation (1970-73) of conservation cropping systems using standard 0.022-acre USLE plotsa.
Cropping system	Rain	Runoff	EI	Soil Loss	Adj'd SLb	SLR
	(in)	(in)		(t/a)	(t/a)
Conv-till Soybeans	53.74	18.66	417	9.41	8.12	0.114
No-till Soybeans	53.00	13.85	423	0.56	0.48	0.007
No-till Soybeans-Wheat Doublecrop	58.53	10.25	488	0.28	0.20	0.003
No-till Corn-Soybean Rotationf	54.02	19.14	433	1.05	0.87	0.012
Corn after Soybeans	57.72	21.00	455	1.37	1.09	0.015
Soybeans after Corn	50.33	17.28	411	0.73	0.64	0.009

^a Adapted from McGregor et al. (1978).
^b Adjusted to EI=360.

Table 10. Erosion evaluation of weed effects in conservation cropping systems for soybeans. Three-year (1978-1981) average soil loss is adjusted for KE=360a.
	SLR	Soil Loss	Runoff
		(t/a)	(%)
Conv-till soybeans:   With weeds	0.103	8.3	42
Without weeds	0.115	9.3	--
Reduced-till soybeans:   With weeds	0.043	3.4	26
Without weeds	0.044	3.6	--
No-till soybeans:   With weeds	0.008	0.6	30
Without weeds	0.010	0.8	--
Reduced-till soybeans-wheat    doublecrop:	0.013	1.0	30

^a Adapted from Mutchler and Greer (1984).

Table 11. Average annual soil loss adjusted to EI=360 and C-factors from conservation tillage systems for soybeans for two different study periodsa.
	Soil Loss, t/a		C-factors
	1970-1973b	1978-1981	1970-1973	1978-1981
No-till	0.5	0.6	0.006	0.008
Conventional-till	8.1	8.3	0.099	0.103
No-till soybeans and wheat, doublecrop	0.2c	--	0.003	--
Reduced-till soybeans and wheat, doublecrop	--	1.0	--	0.013
Reduced-till	--	3.4	--	0.043

^a Adapted from Mutchler and Greer (1984).
^bData from 1970-1973 from K. C. McGregor; C-factors computed from
this data using C=4.471*A/R.
^cData from 1970-1972.

Table 12a. Average annual soil loss and computed C values for corn using various conservation tillage systemsa.
	Soil loss	C Values
	(t/a)	With weeds	w/o weedsb
Conventional-till, grain	7.14	0.089	0.101
Conventional-till, silage	11.20	0.139	0.187
No-till, grain	0.45	0.005	0.010
No-till, silagec	0.27	0.003	0.052
Reduced-till, grain	0.58	0.007	0.015

^a Adapted from McGregor and Mutchler (1983); all values were 4-year
crop year averages, planting to planting (1974-19 77), except those for
no-till silage, which were only 3-year averages (1974-76).
^bw/o = without.
^c No-till silage values averaged over 3 years, all others over 4 years.

Table 12b. Runoff and soil loss from small watersheds using conservation tillage for corn (1975-76).
Watershed treatment	Runoff (in)	Soil Loss(t/a)
No-till silage, 3.88-acre watershed	19.76	0.24
No-till grain, 1.45-acre watershed	19.27	0.21
Reduced-till grain, 1.61-acre watershed	14.99	0.38

Table 13. Comparison of treatmenta values for corn at Holly Springs with soil loss ratios given in AH 537b
	Crop Stagec
	SB	1	2	3	4a	4b	4c	Annuald
Conventional-till, grain
Adjusted data	29	7	9	11	3	4		10
Table 5, line 2e	60	52	41	32	12			30
Conventional-till, silage
Adjusted data	34	8	8	3	27	19	19	19
Table 5, line 10f	75	66	47	27	62			59
No-till, grain
Adjusted data	1.1	1.0	0.4	0.1	1.2	1.8		1.0
Table 5, line 28g	8.0	8.0	8.0	8.0	3.0			6.0
No-till, silage
Adjusted data	4.7	1.2	0.9	0.3	0.9	6.5	11	5
Table 5, line 32h	26.0	24.0	22.0	21.0	34.0			29
Reduced-till, grain
Adjusted data	2.0	1.2	0.5	0.4	1.7	2.8		1.5
Table 5, line 28-29	10.0	10.0	10.0	10.0	4.0			7.0

^aTreatment data were adjusted to eliminate the effect of weeds (Table values adapted from McGregor and Mutchler (1983).
^bWischmeier and Smith (1978).
^cFallow crop stage, F, not shown because it did not occur in our treatments.
^dAnnual C-factor computed by weighting crop stage values with EI distribution from Table 6, AH 537.
^eLine 2 selected for spring residue of 3,400 lb. Cornstalks chopped after harvest and left on the ground giving 70% mulch cover. Table 5C, AH 537, used to determine soil loss ratios for Period 4.
^fRelated corn yields 88 bu/a indicating GP productivity level. Canopy at maturity 70%.
^gCover at planting 70%. Period 4 value from Table 5C, AH 537, using 90% cover after harvest.
^hMulch cover at planting 8%; line 32 lowest cover given. Period 4 value from Table 5C, AH 537, using mulch cover 20% (lowest percentage given) to represent 10% cover from data.

Table 14. Average annual soil loss for cotton tillage treatmentsab.
	SLRc	Soil Lossa	Runoff
		(t/a)	(%)
No-till cotton after reduced-till soybeans:
With weeds	0.102	8.2	38
Without weeds	0.111	8.9	--
With vetch cover	0.014	1.0	18
Reduced-till cotton after no-till fallow:
With weeds	0.058	4.7	28
Without weeds	0.063	5.1	--
No-till cotton after no-till soybeans-wheat doublecrop:With weeds	0.006	0.5	20
Without weeds	0.007	0.6	--
With vetch or wheat cover	0.005	0.4	14
Reduced-till cotton after no-till soybeans-wheat doublecrop:With weeds	0.059	4.8	38
Without weeds	0.077	6.2	--
With vetch or wheat cover	0.053	4.2	22
Conventional-till cotton after 11 years no-till:With weeds	0.217	17.5	35
Without weeds	0.237	19.1	--
With vetch or wheat cover0.142	11.4	27
Conventional-till cotton after 11 years conventional-till:With weeds	0.408	32.8	48
Without weeds	0.411	33.1	--
With vetch or wheat cover	0.133	9.1	26

^aAverage annual soil loss adjusted to R=360.
^bAdapted from Mutchler et al. (1985) and Mutchler and McDowell (1990); values given for weeds that occurred during testing and for weeds analytically removed.
^cAnnual average soil loss ratio is 4.471*SL/EI for years and plots.

Table 15. Erosion from conservation tillage for sorghuma.
Rain (in)	Runoff (in)	EI	Measured Soil loss (t/a)	SLRc	Adjusted Soil lossd (t/a)
CTb sorghum after NTb cotton with vetch cover crop:
41.29	5.51	337	2.39	0.032	2.56
Ridge-till sorghum after CT sorghum:54.59	13.69	410	2.88	0.032	2.53
NT sorghum after NT cotton with wheat cover crop:55.88	5.62	438	0.14	0.001	0.11
NT sorghum after CT cotton with wheat cover:55.88	17.29	438	1.08	0.011	0.89
RTb sorghum after CT cotton with wheat cover:
55.88	10.01	438	1.80	0.018	1.48
CT sorghum after RT cotton with wheat cover:
55.88	12.89	438	4.25	0.043	3.49

^aAdapted from McGregor and Mutchler (1992).
^bCT, RT, and NT is conventional-till, reduced-till, and no-till, respectively.
^cSLR = 4.471 * SL/EI.
^dSoil loss adjusted to correspond to EI=360.

Table 16. Annual average discharge-weighted solution N and P concentrations in runoff (mg/l) and sediment (mg/kg) from corn tillage studiesa.
Plot treatment	Number of storms	Solution N & P			Sedimentb N & P
		NH2	NO3	P	TKN	STP
C-SIL	163	0.31	0.43	0.03	1,864	724
C-GR	159	0.42	0.50	0.08	2,122	807
R-GR	107	0.56	2.03	0.24	4,083	1,353
N-SILc	80	0.44	1.72	0.29	6,254	1,563
N-GR	126	0.46	0.94	0.36	8,622	2,122

^a1975, 1976, and 1977 water years (Oct. 1 through Sept. 30)
^bSediment N is total Kjeldahl nitrogen and STP is sediment total phosphorus.
^cFallowed in 1977 water year; 2-year average listed.

Table 17. Annual average runoff (RO; in), soil loss (SL; t/a), nitrogen and phosphorus losses (lb/a) in corn tillage studiesa.
Plot	RO	SL	Nitrogen losses			Phosphorus losses
			Sol	Sed	Sum	Sol	Sed	Sum
C-SIL	16	10.7	2.7	40.0	42.7	0.1	15.5	15.6
C-GR	15	7.8	3.0	30.8	33.8	0.3	11.9	12.2
R-GR	8	0.6	4.7	5.2	9.9	0.4	1.7	2.1
N-SILb	10	0.3	5.0	4.3	9.3	0.7	1.1	1.8
N-GR	13	0.4	4.1	6.1	10.2	1.1	1.5	2.6

^a1975, 1976, and 1977 water years.
^bFallowed in 1977 water year; 2-year average listed.

Table 18. Three-year annual average concentrations of plant nutrients carried in runoff (mg/l) and on soil loss (mg/kg)a.
Initial date	Crop stageb	Fertilizer method	Solution			Soil loss
			NO3-N	PO4-P	NH4-N	TP	TN
4/27	pl-fert	Insert	0.97	0.53	0.93	2,074	6,964
		Broadcast	2.94	1.80	5.5	2,138	6,107
5/25	sd	Insert	2.81	0.36	0.93	1,794	8,090
		Broadcast	3.34	0.62	1.30	1,066	4,712
10/6	harv	Insert	0.88	0.46	0.82	2,883	9,814
		Broadcast	0.53	0.63	0.77	2,981	12,151
	Av annual	Insert	1.21	0.48	0.88	2,258	7,893
		Broadcast	1.97	1.05	2.58	2,082	7,056

^aConcentrations were calculated by dividing crop stage nutrient losses by the sum of crop stage runoff or soil loss that carried the nutrients.
^bCrop stage length was from begin date of crop stage to begin date of next crop stage.

Table 19. Three-year average annual losses in lb/a of NO3-N, PO4-P, and NH4-N carried in runoff, and TP and TN in soil lossab.
Initial date	Crop stage	Fertilizer method	Solution			Soil loss
			NO3-N	PO4-P	NH4-N	TP	TN
4/27	pl-fert	Insert	0.87	0.48	0.84	0.59	1.99
		Broadcast	2.39	1.46	4.47	0.60	1.71
5/25	sd	Insert	0.94	0.12	0.31	0.11	0.51
		Broadcast	1.51	0.28	0.59	0.11	0.49
10/6	harv	Insert	0.84	0.44	0.78	0.38	1.29
		Broadcast	0.52	0.62	0.76	0.30	1.22
	Av annual	Insert	2.65	1.04	1.92	1.09	3.80
Broadcast		4.43	2.37	5.81	1.01	3.42

^aAmounts of nutrients are the sum of storm losses.
^bValues shown were computed from storm nutrient concentrations and storm runoff and soil loss.

Table 20. Soil loss from ridge-till for sorghum on up-and-down-slope and contoured plotsa.
Soil loss (t/a)
Crop stage	Initial date	Up-and-down- slope	Contour	P-factor Value
4c	1 Jan	2.03	0.61	0.30
4d	1 Mar	0.35	0.16	0.46
SBb	25 Apr	1.37	0.40	0.29
1	30 May	6.12	1.72	0.28
2	4 Jul	0.72	0.35	0.48
3c	18 Jul	0.70	0.15	0.22
4add	28 Aug	0.35	0.18	0.52
4b	26 Oct	0.76	0.29	0.40
	Av annual	3.10	0.96	0.31

^aValues are 4-year crop stage totals.
^bIncludes data for 1 year, no runoff in 3 years.
^cIncludes data for 2 years; canopy less than 75% in 1987 and 1990.
^dIncludes data for 3 years; no runoff in 1987.