EFFECT OF EROSION ON CROP YIELDS ON MAJOR SOIL ASSOCIATIONS
IN WESTERN NORTH DAKOTA

Larry J. Cihacek
NDSU Soil Science Department

and

Tom Conlon
Dickinson Research Center

A study was established in 1987 on Section 24 of the Ranch Headquarters of the Dickinson Research Center on soils mapped as a Cabba-Amor association. Areas of slightly, moderately or severely eroded soil were identified as characterized based on topsoil loss compared to series type description. Samples were collected from 0-6", 6-12", 12-18", 18-24", 24-36" and 36-48" depth increments for characterization for pH, organic matter, total N, NO3 -N, carbonates, texture available water holding capacity bulk density and hydraulic conductivity. Annually, each erosion site was sampled in spring and fall to a depth of 48" for determination of soil moisture and NO3 -N levels. This study was concluded in 1990.

Yield data for each erosion level were collected for barley and either corn or sudangrass in each year of the study from 3 subplots at each erosion level. Table 1 shows barley grain and straw yields for each year and for a 4-year average. The severe erosion site generally gave significantly lower grain yields than the moderately or slightly eroded sites. Although significant differences were not generally noted between erosion levels for straw yields, the numerical trends were similar to grain yields. The general yield relationships for barley grain and straw were slight > moderate > severe erosion.

Similar observations were made for corn and sudangrass dry matter yield with the severely eroded site generally giving significantly lower yields than the moderately or slightly eroded sites (Table 2). The general yield relationships for corn or sudangrass dry matter production were slight > moderate > severe erosion.

Table 1. Erosion effects on barley grain and straw yields. Ranch Headquarters, Dickinson Research Center

Erosion

level

Grain Yields1

Straw Yields1

1987

1988

1989

1990

4-year
average

Percent of maximum yield

1987

1988

1989

1990

4-year
average

Percent of maximum yield

bu/A

%

lb/A

%

Slight

27.6b

4.6b

37.7b

40.5b

27.6b

100

998b

739a

2338a

3202a

1819a

100

Moderate

14.7a

5.2b

24.0ab

27.4a

17.8ab

67

584a

516a

1950a

3006a

1514a

83

Severe

14.9a

1.5a

19.0a

26.8a

15.5a

56

560a

322a

1395a

3367a

1411a

79

1Values followed by the same letter within a given year (column) are not significantly different at P>0.05 as determined by LSD.

 

Table 2. Erosion effects on corn or sudangrass dry-matter production.
Ranch Headquarters, Dickinson Research Center.

Erosion

level

Corn

Sudangrass

Dry Matter Yield1

Dry Matter Yield1

1987

1988

1990

3 yr.

Average

1989

Slight

8560b

982b

1628b

3730b

2337c

Moderate

5632ab

437a

1072ab

2380a

1274b

Severe

3951a

453a

677a

1695a

494a

1Values followed by the same letter within a given year (column) are not significantly different at P<0.05 as determined by LSD.

 

Dickinson Soil Water Summary

Sampling
Date

DPTH
(in)

Ave. T.W.
(In)

Ave A.W.
(In)

22-Aug-85

48

4.60

1.90

25-Oct-85

48

12.18

4.10

 

01-Apr-86

48

12.33

4.25

23-Apr-86

48

12.00

3.92

12-May-86

48

15.77

7.69

28-May-86

48

12.73

4.64

10-Jun-86

48

10.51

2.43

25-Jun-86

48

8.05

-0.03

09-Jul-86

48

9.35

1.27

23-Jul-86

48

9.49

1.41

07-Aug-86

48

7.47

-0.61

22-Aug-86

48

7.29

-0.79

17-Sep-86

48

8.11

0.02

01-Oct-86

48

11.24

3.16

14-Oct-86

48

10.46

2.38

29-Oct-86

48

9.29

1.21

 

22-Apr-87

48

7.80

-0.30

04-May-87

48

8.90

0.81

19-May-87

48

8.23

0.14

01-Jun-87

48

9.46

0.37

15-Jun-87

48

6.66

-1.44

30-Jun-87

48

7.46

-0.63

15-Jul-87

48

8.57

0.48

27-Jul-87

48

9.15

1.05

12-Aug-87

48

7.79

-0.31

24-Aug-87

48

8.43

0.34

 

06-Apr-88

48

9.46

1.37

26-Apr-88

48

8.54

0.45

12-May-88

48

9.57

1.48

26-May-88

48

8.96

0.87

09-Jun-88

48

7.92

-0.17

23-Jun-88

48

7.66

-0.43

07-Jul-88

48

8.29

0.20

21-Jul-88

48

7.85

-0.24

04-Aug-88

48

7.10

-0.99

18-Aug-88

48

7.20

-0.89

01-Sep-88

48

7.11

-0.98

15-Sep-88

48

7.45

-0.64

29-Sep-88

48

7.43

-0.66

13-Oct-88

48

7.56

-0.53

28-Oct-88

48

7.33

-0.76

09-Nov-88

48

7.40

-0.69

 

11-Apr-89

48

8.52

0.43

25-Apr-89

48

7.67

-0.42

09-May-89

48

8.89

0.80

23-May-89

48

8.36

0.26

06-Jun-89

48

8.49

0.40

20-Jun-89

48

7.37

-0.72

05-Jul-89

48

6.77

-1.32

18-Jul-89

48

6.73

-1.36

01-Aug-89

48

6.68

-1.41

15-Aug-89

48

6.34

-1.75

29-Aug-89

48

8.12

0.03

12-Sep-89

48

7.30

-0.79

26-Sep-89

48

7.03

-1.06

10-Oct-89

48

7.66

-0.43

24-Oct-89

48

7.08

-1.01

07-Nov-89

48

8.91

0.82

 

20-Apr-90

48

9.2

1.0

04-May-90

48

8.9

0.8

18-May-90

48

9.1

1.1

01-Jun-90

48

8.8

0.5

18-Jun-90

48

9.3

1.1

02-Jul-90

48

8.3

0.1

12-Jul-90

48

8.2

0.1

27-Jul-90

48

7.5

-0.4

10-Aug-90

48

7.4

-0.7

24-Aug-90

48

7.2

-1.1

10-Sep-90

48

7.6

-0.6

24-Sep-90

48

7.6

-0.6

04-Oct-90

48

7.3

-0.9

19-Oct-90

48

8.3

0.0

02-Nov-90

48

7.8

-0.2

19-Nov-90

48

7.4

-0.6