A review of the use of manure in small-scale crop production systems in South Africa

Journal of Plant Nutrition

Volumn 29, Issue 7, 2006, Pages 1157-1185

  Mkhabela, T ^a  

^a STELLENBOSCH UNIVERSITY   (South Africa)

Author keywords

Maize (Zea mays L.); Manure; Mineralization; Nitrogen; Phosphorus; Small scale farmers; South Africa

Indexed keywords

BOS TAURUS; ZEA MAYS;

EID: 33746795894     PISSN: 01904167     EISSN: 15324087     Source Type: Journal    
DOI: 10.1080/01904160600767179     Document Type: Review

References (124)

1. Adauyi, E. A., and E. E. Ekong. 1981. General agriculture and soils. Book 1. London: Longman.
2. Adey, S., M. D. Laing, and J. V. Da Graça. 1998. Factors influencing crop production in community gardens in KwaZulu-Natal. Applied Plant Science 12(3): 63-66.
3. Anim, F. D. K., and H. D. van Schalkwyk. 1996. Tenure arrangements and access to credit: The case of small-scale farmers in the Northen Province. Agrekon 35(4): 224-230.
4. Bainbridge, S. H., N. Miles, R. Praan, and M. A. Johnston. 1995. Phosphorus sorption in Natal soils. South African Journal of Plant and Soil 12(2): 59-64.
5. Baldock, J. O., and R. B. Musgrave. 1980. Manure and mineral fertilizer effects in continuous and rotational crop sequences in central New York. Agronomy Journal 72: 511-518.
6. Bationo, A., and A. U. Mokwunye. 1991. Role of manure and crop residue in alleviating soil fertility constraints to crop production: With special reference to the Sahelian and Sudanian zones of West Africa. In Alleviating soil fertility constraints to increased crop production in West Africa, ed. A. U. Mokwunye, 217-225. Dordrecht, Netherlands: Kluwer Academic Publishers.
7. Beauchamp, E. G. 1983. Response of corn to nitrogen in pre-plant and side-dress applications of liquid dairy manure. Canadian Journal of Soil Science 63: 377-386.
8. Beauchamp, E. G. 1986. Availability of nitrogen from three manure to corn in the field. Canadian Journal of Soil Science 66: 713-720.
9. Beauchamp, E. G., and J. W. Paul. 1991. A simple method to predict manure N availability to crops in the field. In Nitrogen in organic wastes applied to soils, eds. J. A. Hansen and K. Henrickson, 43-61. Toronto: Academic Press.
10. Bekunda, M. A., A. Bationo, and H. Ssali. 1997. Soil fertility management in Africa: A review of selected research trials. In Replenishing soil fertility in Africa, ed. R. J. Buresh, SSSA Special Publication No. 51, 63-79. Madison, WI: SSSA.
11. Bitzer, C. C., and J. T. Sims. 1998. Estimating the availability of nitrogen in poultry manure through laboratory and field studies. Journal of Environmental Quality 17: 47-54.
12. Bouldin, D. R., N. I. Bhuiyan, and E. T. Grasswell. 1984. Yield and crop parameters of wetland rice as influenced by soil and fertilizer nitrogen. Plant and Soil 79(3): 369-381.
13. Brady, N. C. 1974. The nature and properties of soils, 8th edition, 87-91. New York: MacMillan.
14. Brady, N. C. 1990. The nature and properties of soils, 10th edition. New York: MacMillan.
15. Brinton, W. F. 1985. Nitrogen response of maize to fresh and composted manure. Biological Agriculture and Horticulture 3: 65-83.
16. Campbell, C. A., and W. Souster. 1992. Loss of organic matter and potentially mineralizable nitrogen from Saskatchewan soils due to cropping. Canadian Journal of Soil Science 62: 651-656.
17. Castellanos, J. Z., and P. F. Pratt. 1981. Mineralization of manure nitrogen - correlation with laboratory indexes. Soil Science Society of America Journal 45: 354-357.
18. Chadwick, D. R., F. John, B. F. Pain, B. J. Chambers, and J. Williams. 2000. Plant uptake of nitrogen from organic nitrogen fraction of animal manure: A laboratory experiment. Journal of Agricultural Science 134: 159-168.
19. 15N labelled farmyard manure during soil incubations. Biological Agriculture and Horticulture 10: 255-264.
20. Chescheir, G. M., P. W. Westerman, and L. M. Safley. 1986. Laboratory methods for estimating available nitrogen in manure and sludges. Agricultural Wastes 18: 175-195.
21. Cooper, G. R. 1990. Nitrogen mineralization potentials of barley soils. In Proceedings of 16th Congress of the Soil Science Society of South Africa. Pretoria, South Africa: SSSA.
22. Corales, A. M., and S. R. Serrano. 1999. Factors influencing the utilization of organic fertilizers. PhilRice Technical Bulletin 4: 18-29.
23. De Willigen, P. 1986. Supply of soil nitrogen to the plant during the growing season. In Fundamental, ecological and agricultural aspects of nitrogen metabolism in higher plants, ed. H. Lambers, 417-432. Dordrecht, Netherlands: Martinus Nijhoff Publishers.
24. Du Toit, M.E., and C. C. Du Preez. 1995. Effect of cultivation on the nitrogen fertility of selected dryland soils. South African Journal of Plant and Soil 12(2): 73-81.
25. Eckert, H., and H. Bergmann. 1990. Effects of monoethanolamine on growth and biomass formation of rye and barley. Plant Growth Regulations (Netherlands) 9(1): 1-8.
26. Ekbladh, G. 2000. Seasonal availability of N from composted cattle manure and poultry manure in field and incubation studies. Biological Agriculture and Horticulture 18: 161-174.
27. Enyong L. A., S. K. Debrah, and A. Bationo. 1999. Farmer's perceptions and attitudes towards introduced soil-fertility enhancing technologies in western Africa. Nutrient Cycling in Agroecosystems 53(2): 177-188.
28. Evers, G. W. 1998. Comparison of broiler poultry litter and commercial fertilizer for coastal Bermuda grass production in the Southeastern U.S. Journal of Sustainable Agriculture 12(4): 55-77.
29. Food and Agriculture Organization (FAO). 1992. Fertilizer yearbook, Volume 42. Rome: Food and Agriculture Organization.
30. Farina, M. P. W., and P. Channon. 1991. A field comparison of lime requirement indices for maize. Plant and Soil 143: 127-135.
31. Fey, M. V. 1981. Aluminium toxicity. Arena Agricultural Region, Natal: Soils 4(1): 15.
32. Fixen, P. E., and J. H. Grove. 1991. Testing soils for phosphorus. In Soil testing and plant analysis, ed. R. L. Westerman. Madison, WI: American Society of Agronomy.
33. Fertilizer Society of South Africa (FSSA). 1989. Fertilizer handbook, 3rd edition. Hennopsmeer, South Africa: Fertilizer Society of South Africa.
34. FSSA. 1997. Fertilizer promotion and extension in Southern Africa. Plant Food 7(2): 4-6.
35. Gerner, H., and G. Harris. 1993. The use and supply of fertilizers in sub-Saharan Africa. In The role of plant nutrients for sustainable crop production in sub-Saharan Africa, eds. H. van Reuler and W. H. Prins, 107-125. Leidscherndam, Netherlands: Dutch Association of Fertilizer Producers.
36. Hades, A., S. Feigenbaum, A. Feigin, and R. Portnoy. 1986. Nitrogen mineralization rate in profiles of differently managed soil types. Soil Science Society of America Journal 50: 314-319.
37. Hassink, J., L. A. Bouwman, K. B. Zwart, J. Bloom, and L. Brussaard. 1993. Relationships between soil texture, physical protection of organic matter, soil biota, and C and N mineralization in grassland soils. Geoderma 57: 105-128.
38. Hassink, J., A. M. Neutel, and P. C. de Ruiter. 1994. C and N mineralization in sandy and loamy grassland soils: The role of microbes and micro-fauna. Soil Biology and Biochemistry 26: 1565-1571.
39. Haynes, R. J. 1984. Animal manure make good fertilisers. New Zealand Journal of Agriculture 149: 22-23.
40. Hèbert, M., A. Karam, and L. E. Parent. 1991. Mineralization of nitrogen and carbon in soils amended with composted manure. Biol. Agric. Hortic. 7: 349-361.
41. Holliday, R., P. M. Harris, and M. R. Baba. 1965. Investigations into the mode of action of farm yard manure. Journal of Agricultural Science 64: 161-166.
42. Hountin, J. A., D. Coulillard, and A. Karam. 1997. Soil carbon, nitrogen and phosphorus contents in maize plots after 14 years of pig slurry applications. Journal of Agricultural Science 129: 187-191.
43. Hue, N. V., and I. Amein. 1989. Aluminium detoxification with green manure. Communications in Soil Science and Plant Analysis 20 (15&16): 1499-1511.
44. Jokela, W. E. 1992. Nitrogen fertilizers and dairy manure effects on corn yield and soil nitrate. Soil Science Society of America Journal 56(1): 148-154.
45. Jones, M. E., R. R. Harwood, N. C. Dehne, J. Smeek, and E. Parker. 1998. Enhancing soil nitrogen mineralization and corn yield with over-seeded cover crops. Soil Water Conservation 53(3): 245-249.
46. Karlen, D. L., R. L. Flannery, and E. J. Sadler. 1987. Nutrient and dry matter accumulation rates for high yielding maize.Journal of Plant Nutrition 10: 1409-1417.
47. Keeney, D. R., and D. W. Nelson. 1982. Nitrogen-availability indices. In Methods of soil analysis. Part 2. Chemical and microbiological properties, 2nd edition, eds. A. L. Page, R. H. Miller, and D. R. Keeney, 643-698. Madison, WI: ASA-SSSA.
48. Kirchmann, H. 1985. Losses, plant uptake and utilisation of manure nitrogen during a production cycle. Acta Agriculturae Scandinavica Supplementum 24: 77.
49. Kirchmann, H. 1991. Carbon and nitrogen mineralization in fresh and anaerobic animal manure during incubation with soil. Sweden Journal of Agricultural Research 21: 165-173.
50. Kirchmann, H., and A. Lundvall. 1993. Relationship between N immobilization and volatile fatty acids in soils after application of pig and cattle slurry. Biology and Fertility of Soils 15: 161-164.
51. 3 conversion from dairy manure on the yield of corn. Agronomy Journal 73: 720-723.
52. Klausner, S. D., V. R. Kanneganti, and D. R. Bouldin. 1994. An approach for estimating a decay series for organic nitrogen in animal manure. Agronomy Journal 86: 897-903.
53. Ladd, J. N., M. Amato, and J. M. Oades. 1985. Decomposition of plant material in Australian soils. III. Residual organic and microbial biomass C and N from isotope-labelled legume material and soil organic matter, decomposing under field conditions. Australian Journal of Soil Research 23: 603-611.
54. Linquist, B. A., P. W. Singleton, K. G. Cassman, and K. Keane. 1996. Residual phosphorus and long-term management strategies for an Ultisol. Plant and Soil 184: 47-55.
55. Lou, A., and S. Sun. 1994. Effects of organic manure on the biological activities associated with insoluble P releases in a Blue Purple paddy soil. Communications in Soil Science and Plant Analysis 25(13&14): 2513-2522.
56. Lungu, O. I., J. Temba, B. Chirwa, and C. Lungu. 1993. Effects of lime and farmyard manure on soil acidity and maize growth on acid Alfisol from Zambia. Tropical Agriculture (Trinidad) 70(4): 309-314.
57. Magdoff, F. R. 1991. Understanding the Magdoff pre-sidedress nitrate test for corn. Journal of Production Agriculture 4: 297-305.
58. Mahimairaja, S., N. S. Bolan, and M. J. Hedley. 1995. Agronomic effectiveness of poultry manure composts. Communications in Soil Science and Plant Analysis 26(11&12): 1843-1861.
59. Manson, A. D. 1996. The fertility status of land used for small-scale cropping in KwaZulu-Natal, Cedara Report No. N/A/96/9. Pietermaritzburg, South Afria: KwaZulu Natal Department of Agriculture.
60. Manson, A. D., N. Miles, and M. P. W. Farina. 1999. The Cedara Computerized Fertilizer Advisory Service (FERTREC): Explanatory notes and crop and soil norms. Pietermaritzburg, South Africa: KwaZulu-Natal Department of Agriculture.
61. Materechera, S. A., W. Van Averbeke, J. Yoganthan, and P. Harris. 1998. Current and potential role of manure for soil fertility management in the small-scale farming sector of South Africa. Paper presented at Joint Congress of the South African Society of Crop Production and Soil Science Society of South Africa on "Soils and Crops Towards 2000," Alpine Heath, KwaZulu-Natal, South Africa, January 20-22, 1998.
62. Metho, L. 2001. Small-scale maize inter-cropping production. In Ezolimo neZemvelo News, 1st edition. Pietermaritzburg, South Africa: KwaZulu-Natal Department of Agriculture and Environmental Affairs.
63. Miles, N. 1991. Chicken litter as a fertilizer for pastures. In Fertilizer advisory news and views. Pietermaritzburg, South Africa: Department of Agricultural Development, Natal Region.
64. Mkile, Z. 2000. Harness the riches of kraal manure. Farmer's Weekly June 30: 22-25.
65. Mokwunye, U. 1980. Interaction between farmyard manure and NPK fertilizers in Savanna soils. In Inorganic recycling in Africa, FAO Soils Bulletin 43. Rome: FAO.
66. Motavalli, P. P., K. A. Kelling, and J. C. Converse. 1989. First-year nutrient availability from injected dairy manure. Journal of Environmental Quality 18: 180-185.
67. Murwira, H. K., and H. Kirchmann. 1993. Nitrogen dynamics and maize growth in a Zimbabwean sandy loam under manure fertilization. Communications in Soil Science and Plant Analysis 24: 2343-2359.
68. Murwira, H. K., M. J. Swift, and P. G. H. Frost. 1993. Manure as a key resource in sustainable agriculture. In Livestock and sustainable nutrient cycling in mixed farming systems of sub-Saharan Africa II, eds. J. M. Powell, S. Fernandez-Rivera, T. O. Williams, and C. Renard, 131-148. Addis Ababa: International Livestock Centre for Africa (ILCA).
69. Mugwira, L. M., and L. M. Mukurumbira. 1986. Nutrient supplying power of different groups of manure from communal areas and commercial feedlots. Zimbabwe Agriculture Journal 83: 25-29.
70. Myers, R. J. K., C. A. Palm, E. Cuevas, I. U. N. Gunatilleke, and M. Brossard. 1994. The synchronization of nutrient mineralization and plant nutrient demand. In The management of tropical soil biology and fertility, eds. P. L. Woomer and M. J. Swift. Chichester, UK: Wiley-Sayce.
71. Nambiar, K. K. M., and I. P. Ambrol. 1989. Long term fertilizer experiments in India: An overview. Fertilizer News 1: 1-22.
72. Nicholson, F. A., B. J. Chambers, K. A. Smith, and R. Harrison. 1999. Spring applied organic manure as a source of nitrogen for cereals: Experiments using field scale equipment. Journal of Agricultural Science 133: 353-363.
73. Nyakatawa, E. Z., K. C. Reddy, and G. F. Brown. 2001. Residual effect of poultry litter applied to cotton in conservation tillage systems on succeeding rye and corn. Journal of Sustainable Agriculture 71: 159-171.
74. Ohno, T., and B. S. Crannell. 1996. Green and animal manure-derived dissolved organic matter effects on phosphorus sorption. Journal of Environmental Quality 25: 1137-1143.
75. Padwick, G. W. 1983. The maintenance of soil fertility in tropical Africa: A review. Experimental Agriculture 19: 293-310.
76. Pang, X. P., and J. Letey. 2000. Organic farming: Challenge of timing nitrogen availability to crop nitrogen requirements. Soil Science Society of America Journal 64: 247-253.
77. Paul, J. W., and E. G. Beauchamp. 1989. Effect of carbon constituents in manure on denitrification in soil. Canadian Journal of Soil Science 69: 49-61.
78. Paul, J. W., and E. G. Beauchamp. 1994. Short term nitrogen dynamics in soil amended with fresh and composted cattle manure. Canadian Journal of Soil Science 74: 147-155.
79. 4. Canadian Journal of Soil Science 75: 35-42.
80. Pratt, P. F., F. E. Broadbent, and J. P. Martin. 1973. Using organic wastes as nitrogen fertilizers. California Agriculture 27(6): 10-13.
81. Probert, M. E., J. R. Okalebo, and R. K. Jones. 1995. The use of manure on small-holders' farms in semi-arid eastern Kenya. Experimental Agriculture 31: 371-381.
82. Rao, S. C., and T. H. Dao. 1996. Nitrogen placement and tillage effects on dry matter and nitrogen accumulation and redistribution in winter wheat. Agronomy Journal 88: 365-371.
83. Reddy, D. D., A. S. Rao, K. S. Reddy, and P. N. Takkar. 1999. Yield sustainability and phosphorus utilization in soybean-wheat system on Vertisols in response to integrated use of manure and fertilizer phosphorus. Field Crops Research 62: 181-190.
84. Roberts, V. G., and Z. Smeda. 2001. The distribution of soil fertility constraints in KwaZulu-Natal, South Africa. In 5th International Symposium on Plant-Soil Interactions at Low pH (Abstract only), 12. Alpine Heath, South Africa: Agricultural Research Council (ARC).
85. Robinson, J. S., and A. N. Sharpley. 1996. Reaction in soil of phosphorus released from poultry litter. Soil Science Society of America Journal 60: 1583-1588.
86. Sanchez, P. A., K. D. Shepherd, M. J. Soule, F. M. Place, R. J. Buresh, A.-M. N. Izac, A. U. Mokwunye, F. R. Kwesiga, C. G. Ndiruti, and P.L. Woomer. 1997. Soil fertility replenishment in Africa: An investment in natural resource capital. In Replenishing soil fertility in Africa, eds. R. J. Buresh et al., 1-46, SSSA Special Publication 51. Madison, WI: SSSA.
87. Saunders, D. H., and P. M. Grant. 1962. Rate of mineralization of organic matter in cultivated Rhodesian soils. Transactions Communication IV & V: 235-239.
88. Schmitt, M. A., J. E. Sawyer, and R. G. Hoeft. 1992. Incubation of injected liquid beef manure: Effect of time and manure rate. Agronomy Journal 84: 224-228.
89. Scott, P. D. 1986. The production of organic fertilizer, 25-28. Hennospmeer, South Africa: Fertilizer Society of South Africa.
90. Serna, M. D., and F. Pomares. 1991. Comparison of biological and chemical methods to predict nitrogen mineralization in animal wastes. Biology and Fertility of Soil 12: 89-94.
91. Sharma, S. N., R. Prasad, S. Singh, and P. Singh. 2000. On-farm trials of the effect of introducing a summer green manure of mungbean on the productivuty of a rice-wheat cropping system. Journal of Agricultural Science 134: 169-172.
92. Sharpley, A. N., and I. Sisak. 1997. Differential availability of manure and inorganic sources of phosphorus in soil. Soil Science Society of America Journal 61: 1503-1508.
93. Sharpley, A. N., and S. J. Smith. 1989. Mineralization and leaching of phosphorus from soil incubated with surface-applied and incorporated crop residue. Journal of Environmental Quality 18: 101-105.
94. Sharpley, A. N., S. J. Smith, J. W. B. Steward, and A. C. Mathers. 1997. Phosphorus forms in soil receiving cattle feedlot waste. Soil Science Society of America Journal 61: 1503-1505.
95. Sidhu, A. S., and H. S. Sur. 1993. Effect of incorporation of legume straw on soil properties and crop yield in a maize-wheat sequence. Tropical Agriculture 70: 226-229.
96. Siman, G. 1987. Utilization of nitrogen from slurry to fodder crops. In Animal manure on grassland and fodder crops: Fertilizer or waste? ed. H. G. Van Der Meer, Research Report from the Nordic Countries, Denmark, Finland and Sweden. Boston: M. Nijhoff Publishers.
97. Sims, J. T., and D. C. Wolf. 1994. Poultry waste management: Agricultural and environmental issues. Advances in Agronomy 52: 1-74.
98. Singh, R. K., R. De, and B. B. Turkhede. 1986. Time of application of farmyard manure and fertiliser nitrogen on the growth, yield and nutrient uptake of dryland wheat. Journal of Agricultural Science (Cambridge) 106: 7-15.
99. Singh, R. S., A. S. Raghubanshi, and J. S. Singh. 1991. Nitrogen mineralization in dry tropical Savanna: Effects of burning and grazing. Soil Biology and Biochemistry 23: 269-273.
100. Smaling, E. 1993. An agro-ecological framework for integrated nutrient management with special reference to Kenya, PhD Diss., Agricultural University.
101. Smaling, E. M., and A. R. Braun. 1996. Soil fertility research in sub-Saharan Africa: New dimensions, new challenges. Communications in Soil Science and Plant Analysis 27: 365-386.
102. Smith, C. K., A. D. Munson, and M. R. Coyea. 1998. Nitrogen and phosphorus release from humus and mineral soil under black spruce forests in central Quebec. Soil Biology and Biochemistry 30 (12): 1491-1500.
103. Sørensen, L. H. 1981. Carbon-nitrogen relationships during the humification of cellulose in soils containing different amounts of clay. Soil Biology and Biochemistry 13: 313-321.
104. Sørensen, P., and E. R. Jensen. 1995. Mineralization- immobilization and plant uptake of nitrogen as influenced by the spatial distribution of cattle slurry in soils of different texture. Plant and Soil 173: 283-291.
105. 15N-labelled organic nitrogen in sheep manure applied to soils of different texture under field conditions. Plant and Soil 162: 39-47.
106. Strong, D. T., P. W. G. Sale, and K. R. Helyar. 1999. The influence of the soil matrix on nitrogen mineralization and nitrification. IV. Texture. Australian Journal of Soil Research 37: 329-344.
107. Swift, M. J., P. G. H. Frost, B. M. Campbell, J. C. Hatton, and K. B. Wilson. 1989. Nitrogen cycling in farming systems derived from savanna. In Ecology of arable land: Development in plant and soil sciences, eds. M. Clarholm and L. Bergstrom, Volume 39, 63-67. Dordrecht, Netherlands: Kluwer Academic Publishers.
108. Tanner, P. D., and L. Mugwira. 1984. Effectiveness of communal area manure as sources of nutrients for young maize plants. Zimbabwe Agriculture Journal 81: 31-35.
109. Thomas, N. P. 1988. Soil management options to reduce runoff and erosion on a hard-setting Alfisol in the semi-arid tropics. Soil Tillage Research 25(2-3): 195-215.
110. Van der Mey, G. A., H. M. Combrink, and C. C. Du Preez. 1994. Nitrogen mineralization in selected soils from the maize producing areas in South Africa. South African Journal of Plant Soil 11(2): 64-70.
111. Van Faasen, H. G., and H. van Dijk. 1987. Manure as a source of nitrogen and phosphorus in soils. In Animal manure on grassland and fodder crops, eds. H. G. van der Meer, R. J. Unwin, T. A. van Dijk, and G. C. Ennik, 25-45. Dordrecht, Netherlands: Martinus Nijhoff Publishers.
112. Van Noordwijk, M., G. H. Dijksterhuis, and H. Van Keulen. 1994. Risk management in crop production and fertilizer use with uncertain rainfall: How many eggs in which baskets. Netherlands Journal of Agricultural Science 42(4): 249-269.
113. Van Veen, J. A., and P. J. Kuikman. 1990. Soil structure aspects of decomposition of organic matter by micro-organisms. Biochemistry 11: 213-233.
114. Wallingford, G. W., L. S. Murphy, W. L. Powers, and H. L. Manges. 1975. Effects of beef feedlot manure and lagoon water on iron, zinc, manganese and copper content in corn and DTPA soil extracts. Soil Science Society of America Journal 39: 482-487.
115. White, R. E. 1989. Introduction to the principles and practice of soil science, 187. New York: John Wiley.
116. Wild, A. 1988. Plant nutrients in soil: Nitrogen. In Russell's soil conditions and plant growth, 11th edition, ed. A. Wild. Harlow, UK: Longman.
117. Williams, J. H., and G. W. Cooke. 1981. Effect of seed irradiation on genetic variation of oil and protein content of soybeans. Crop Science 1: 38-41.
118. Williams, T. O. 1999. Factors influencing manure application by farmers in semi-arid West Africa. Nutrient Cycling in Agroecosystems 55: 15-22.
119. Williams, T. O., J. M. Powell, and S. Fernández-Rivera. 1995. Soil fertility maintenance and food crop production in semi-arid West Africa: Is reliance on manure a sustainable strategy? In Proceedings of the Conference on Livestock and Sustainable Nutrient Cycling in Mixed Farming Systems of Sub-Saharan Africa II, eds. M. S. Powell, S. Fernandez-Rivera, T. O. Williams, and C. Renard, 43-47. Addis Ababa. Ethiopia: ILCA.
120. Woods, C. W., H. A. Torbert, and D. P. Delany. 1993. Poultry litter as a fertilizer for Bermuda grass: effects on yield and quality. Journal of Sustainable Agriculture 3: 21-37.
121. Xie, R., and A. F. MacKenzie. 1986. Urea and manure effects on soil nitrogen and corn dry matter yields. Soil Science Society of America Journal 50(6): 1504-1509.
122. Yadvinder-Singh, Bijay-Singh, M. S. Maskina, and O. P. Meelu. 1988. Effects of organic manure, crop residues and green manure (Sesbania aculeata) on nitrogen and phosphorus transformation in a sandy loam at field capacity and waterlogged conditions. Biology and Fertility of Soil 6: 183-187.
123. Yoghanathan, S., and W. van Averbeke. 1996. On the manuring practices by black small farmers in the border and Ciskei regions of the eastern Cape and the value of local kraal manure as a fertilizer. In Proceedings of the South African Society of Crop Production Conference. Bloemfontein, South Africa: SASCP.
124. Zebarth, B. J., J. W. Paul, O. Schmidt, and R. McDougall. 1996. Influence of the time and rate of liquid-manure application on yield and nitrogen utilization of silage corn in south coastal British Columbia. Canadian Journal of Soil Science 76: 153-164.