Agriculture Reference
In-Depth Information
TABLE 8.5
C/N Ratio of Straw of Major Cereal and Legume Crops
Growth Stage/Age
in Days
C/N
Ratio
Crop Species
Reference
Corn residues (
Zea mays
L.)
Physiological maturity
67
Burgess et al. (2002)
Rice straw (
Oryza sativa
L.)
Physiological maturity
69
Eagle et al. (2001)
Rice straw (
Oryza sativa
L.)
Physiological maturity
56
Davelouis et al. (1991)
Sorghum (
Sorghum bicolor
L. Moench)
Vegetative
22.0
Clement et al. (1998)
Barley straw (
Hordeum vulgare
L.)
Physiological maturity
99.1
Larnez and Janzen (1996)
Ryegrass (
Lolium multiflorum
Lam)
Vegetative
30
Kuo and Jellum (2002)
Rye (
Secale cereale
L.)
Heading
40
Rannells and Wagger (1996)
Alfalfa hay (
Medicado sativa
L.)
Not given
15.9
Larney and Janzen (1996)
Pea straw (
Pisum sativum
L.)
Physiological maturity
21
Fauci and Dick (1994)
Pea hay (
Pisum sativum
L.)
Not given
15.4
Larnez and Janzen (1996)
Red clover (
Trifolium pratense
L.)
101 days
13.7
Kirchmann (1988)
White clover (
Trifolium repens
L.)
101 days
10.7
Kirchmann (1988)
Yellow trefoil (
Medicago lupulina
L.)
101 days
10.1
Kirchmann (1988)
Persian clover (
Trifolium resupinatum
L.)
101 days
15.8
Kirchmann (1988)
Egyptian clover (
Trifolium alexandrium
L.)
101 days
16.7
Kirchmann (1988)
Subterranean clover (
Trifolium subterraneum
L.)
101 days
11.4
Kirchmann (1988)
Cowpea (
Vigna unguiculata
L. Walp.)
Green pods
13.9
Clement et al. (1998)
Sunnhemp (
Crotalaria juncea
L.)
Mature pods
20.2
Clement et al. (1998)
Soybean (
Glycine max
L. Merr.)
Vegetative
17.9
Clement et al. (1998)
Pigeon pea (
Cajanus cajan
L. Millspaugh)
Not given
25.9
Clement et al. (1998)
Wild indigo (
Indigofera tinctoria
L.)
Flowering
15.8
Clement et al. (1998)
Sesbania (
Sesbania rostrata
Bremek & Oberm)
Vegetative
27.8
Clement et al. (1998)
Sesbania (
Sesbania emerus
Aubl. Urb.)
Vegetative
26.5
Clement et al. (1998)
Hairy vetch (
Vicia villosa
Roth)
Vegetative
12
Kuo and Jellum (2002)
Hairy vetch (
Vicia villosa
Roth)
Flowering
18
Sainju et al. (2002)
Hairy vetch (
Vicia villosa
Roth)
Early bloom
17
Rannelles and Wagger (1996)
Crimson clover (
Trifolium incarnatum
L.)
Midbloom
11
Rannelles and Wagger (1996)
Tropical kudzu (
Pueraria phaseoloides
)
Not given
19
Davelouis et al. (1991)
Source:
Adapted from Burgess, M. S., G. R. Mehuys, and C. A. Madramootoo. 2002.
Soil Sci. Soc. Am. J.
66:1350-1358;
Clement, A., J. K. Ladha, and F. P. Chalifour. 1998.
Agron. J.
90:149-154; Davelouis, J. R., P. A. Sanchez, and J.
C. Alegre. 1991.
TropSoils Technical Report 1988-1989
, pp. 286-289. Raleigh, NC: North Carolina State
University; Kirchmann, H. 1988.
Acta Agric. Cand
. 38:25-31; Kuo, S. and E. J. Jellum. 2002.
Agron. J
. 94:501-
508; Larney, F. J. and H. H. Janzen. 1996.
Agron. J
. 88:921-927; Eagle, A. J. et al. 2001.
Agron. J
. 93:1346-1354;
Fauci, M. F. and R. P. Dick. 1994.
Soil Sci. Soc. Am. J
. 58:134-138; Rannells, N. N. and M. J. Wagger. 1996.
Agron. J.
88:777-782; Sainju, U., Singh, B. P., and S. Yaffa. 2002.
Agron. J.
94:594-602.
Benjamin et al., 2010; Halvorson and Schlegel, 2012). Follett et al. (2005) reported an increase in
SOC under an irrigated, no-till (NT) production system with high N fertility in Mexico. Varvel and
Wilhelm (2008) reported significant increases in SOC levels in the 0-7.5 cm soil depth for irrigated
continuous corn and corn-soybean rotations in Nebraska.
8.2.2.7 Use of Cover Crops
Cover crops have been shown to provide many beneficial effects on crop growth and development,
if properly managed. The beneficial effects of cover crops include reduced soil erosion, increased
biological diversity (i.e., microbes, insects, and birds), increased nutrient cycling and biological N
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