The publications cited in the text (in parentheses) are listed here by reference number.

1 Abdul-Baki, A. A. et al. 1997. Broccoli production in forage soybean and foxtail millet cover crop mulches. HortSci. 32:836-839.

2 Abdul-Baki, A. A. and J. R. Teasdale. 1993. A no-tillage tomato production system using hairy vetch and subterranean clover mulches. HortSci. 28:106-108.

3 Abdul-Baki, A. A. and J. R. Teasdale. 1997. Snap bean production in conventional tillage and in no-till hairy vetch mulch. HortSci. 32:1191-1193.

4 Abdul-Baki, A. A. and J. R. Teasdale. 1997. Sustainable Production of Fresh-Market Tomatoes and Other Summer Vegetables with Organic Mulches. Farmers’ Bulletin No. 2279, USDA /ARS, Beltsville, MD.

5 Alabouvette, C., C. Olivain and C. Steinberg. 2006. Biological control of plant diseases: the European situation. European J. of Plant Path. 114:329-341.

6 Alger, J. 2006. Personal communication. Stanford, Mont.

7 Al-Sheikh, A. et al. 2005. Effects of potato-grain rotations on soil erosion, carbon dynamics and properties of rangeland sandy soils. J. Soil Tillage Res. 81:227-238.

8 American Forage and Grassland Council National Fact Sheet Series. Subterranean clover.

9 Angers, D. A. 1992. Changes in soil aggregation and organic carbon under corn and alfalfa. Soil Sci. Soc.Am. J. 56:1244-1249.

10 ATTRA. 2006. Overview of Cover Crops and Green Manures. ATTRA. Fayetteville, Ark.

11 ATTRA. Where can I find information about the mechanical roller-crimper used in no-till production?

12 Arshad, M. A. and K. S. Gill. 1996.Crop production, weed growth and soil properties under three fallow and tillage systems. J. Sustain. Ag. 8:65-81.

13 Ashford, D. L. and D. W. Reeves, 2003. Use of a mechanical roller-crimper as an alternative kill method for cover crops. Amer. J. Alt. Ag. 18:37-45.

14 Badaruddin, M. and D. W. Meyer. 1989. Water use by legumes and its effects on soil water status. Crop Sci. 29:1212-1216.

15 Badaruddin, M. and D. W. Meyer. 1990.Green manure legume effects on soil nitrogen, grain yield, and nitrogen nutrition of wheat. Crop Sci. 30:819-825.

16 Bagegni, A. M. et al. 1994. Herbicides with crop competition replace endophytic tall fescue (Festuca arundinacae). Weed Tech. 8:689-695.

17 Bailey, R. G. et al. 1994. Ecoregions and subregions of the United States (map).Washington, DC:USDA Forest Service.1:7, 500,000. With supplementary table of map unit descriptions, compiled and edited by W. H. McNab and R. G. Bailey.

18 Ball, D. M. and R. A. Burdett. 1977. Alabama Planting Guide for Forage Grasses. Alabama Cooperative Extension Service, Chart ANR 149. Auburn Univ., Auburn, Ala.

19 Ball, D. M. and R. A. Burdett. 1977. Alabama Planting Guide for Forage Legumes. Alabama Cooperative Extension Service, Chart ANR 150. Auburn Univ., Auburn, Ala.

20 Barker, K. R. 1996. Animal waste, winter cover crops and biological antagonists for sustained management of Columbia lance and other nematodes on cotton. SARE Project Report #LS95- 060.1. Southern Region SARE. Griffin, GA.

21 Barnes, R. F. et al. 1995. Forages: The Science of Grassland Agriculture. 5th Edition. Iowa State Univ. Press, Ames, Iowa.

22 Bauer, P. J. et al. 1993.Cotton yield and fiber quality response to green manures and nitrogen. Agron. J. 85:1019-1023.

23 Bauer, P. J., J. J. Camberato and S. H. Roach. 1993.Cotton yield and fiber quality response to green manures and nitrogen. Agron. J. 85:1019- 1023

24 Bauer P. J. and D. W. Reeves. 1999. A comparison of winter cereal species and planting dates as residue cover for cotton grown with conservation tillage. Crop Sci. 39:1824–1830.

25 Baumhardt, R. L. and R. J. Lascano. 1996. Rain infiltration as affected by wheat residue amount and distribution in ridged tillage. Soil Sci. Soc. Am. J. 60:1908-1913.

26 Baumhardt, R. L. 2003. The Dust Bowl Era. In B. A. Stewart and T. A. Howell (eds.) Encyclopedia of Water Science, pp. 187-191. Marcel-Dekker, NY.

27 Baumhardt, R. L. and R. L. Anderson. 2006. Crop choices and rotation principles. In G. A. Peterson, P. W. Unger, and W. A. Payne (eds.) Dryland Agriculture, 2nd ed. Agronomy Monograph No. 23. pp. 113-139. ASA, CSSA, and SSSA, Madison, WI.

28 Baumhardt, R. L. and R. J. Lascano. 1999. Water budget and yield of dryland cotton intercropped with terminated winter wheat. Agron. J. 91:922-927.

29 Baumhardt, R. L. and J. Salinas-Garcia. 2006. Mexico and the US Southern Great Plains. In G. A. Peterson, P. W. Unger, and W. A. Payne (eds.) Dryland Agriculture, 2nd ed. Agronomy Monograph No. 23. pp. 341-364.ASA, CSSA, and SSSA, Madison, WI.

30 Beale, P. et al. 1985. Balansa Clover— a New Clover-Scorch-Tolerant Species. South Australia Dept. of Ag. Fact Sheet.

31 Beste, C. E. 2007. Personal communication. Univ. of Maryland-Eastern Shore, Salisbury, MD.

32 Blackshaw, R. E. et al. 2001a.Yellow sweetclover, green manure, and its residues effectively suppresses weeds during fallow. Weed Sci. 49:406-413.

33 Blackshaw, R. E. et al. 2001b. Suitability of undersown sweetclover as a fallow replacement in semiarid cropping systems. Agron. J. 93:863- 868.

34 Blaser, B.C. et al. 2006.Optimizing seeding rates for winter cereal grains and frost-seeded red clover intercrops. Agron J. 98:1041-1049.

35 Bloodworth, L. H. and J. R. Johnson. 1995. Cover crops and tillage effects on cotton. J. Prod. Ag. 8:107-112.

36 Boquet, D. J. and S. M. Dabney. 1991. Reseeding, biomass, and nitrogen content of selected winter legumes in grain sorghum culture. Agron. J. 83:144-148.

37 Bordovsky, D. G., M. Choudhary and C. J. Gerard. 1998. Tillage effects on grain sorghum and wheat yields in the Texas Rolling Plains. Agron. J. 90:638–643.

38 Bowman, G. 1997. Steel in the Field: A Farmer’s Guide to Weed Management Tools. USDA-Sustainable Agriculture Network (SAN). Beltsville, MD.

39 Boydston, R. A. and K. Al-Khatib. 2005. Utilizing Brassica cover crops for weed suppression in annual cropping systems. pp. 77-94. In H. P. Singh, D. R. Batish and R. K. Kohli (eds.). Handbook of Sustainable Weed Management. Haworth Press, Binghamton, NY.

40 Bradow, J. M. and J. C. William Jr. 1990. Volatile seed germination inhibitors from plant residues. J. Chem. Ecol. 16:645-666.

41 Bradow, J. M. 1993. Inhibitions of cotton seedling growth by volatile ketones emitted by cover crop residues. J. Chem. Ecol. 19:1085-1108.

42 Brady, N.C. 1990. The Nature and Properties of Soils. Macmillan Pub. Co., N.Y.

43 Brainard. D. 2005. Screening of cowpea and soybean varieties for weed suppression. Cornell Univ.

44 Brandt, J. E., F. M. Hons and V. A. Haby. 1989. Effects of subterraneum clover interseeding on grain yield, yield components, and nitrogen content of soft red winter wheat. J. Prod. Agric. 2:347-351.

45 Brennan, E.B. and R.F. Smith. 2005.Winter cover crop growth dynamics and effects on weeds in the Central Coast of California. Weed Tech. 119: 1017-1024.

46 Brinsfield, R. and K. Staver. 1991. Role of cover crops in reduction of cropland nonpoint source pollution. Final Report to USDA-SCS, Cooperative Agreement #25087.

47 Brinton, W. Medics, general. Univ. of Calif. SAREP Cover Crops Resource Page.

48 Brown, P. D. and M. J. Morra. 1997. Control of soil-borne plant pests using glucosinolate-containing plants. pp. 167–215. In: D. L. Sparks (ed.) Adv. Agron. Vol. 61.Academic Press, San Diego, Ca.

49 Brown, S. et al. 2001. Tomato Spotted Wilt of Peanut: Identifying and Avoiding High-Risk Situations. Univ of Georgia Cooperative Extension Service Bulletin 1165.Univ of Georgia, Athens, GA.

50 Bruce, R. R, P. F. Hendrix and G. W. Langdale. 1991. Role of cover crops in recovery and maintenance of soil productivity. pp.109-114. In W. L. Hargrove (ed.). Cover Crops for Clean Water. Soil and Water Conservation Society. Ankeny, Iowa.

51 Bruce, R. R., G. W. Langdale and A. L. Dillard. 1990. Tillage and crop rotation effect on characteristics of a sandy surface soil. Soil Sci. Soc. Am. J. 53:1744-1747.

52 Bruce, R. R. et al. 1992. Soil surface modification by biomass inputs affecting rainfall infiltration. Soil Sci. Soc. Am. J. 56:1614-1620.

53 Brunson, K. E. 1991. Winter cover crops in the integrated pest management of sustainable cantaloupe production. M. S. Thesis. Univ. of Georgia, Athens, GA.

54 Brunson, K. E. and S.C. Phatak. 1990.Winter cover crops in low-input vegetable production. HortSci. 25:1158.

55 Brunson, K. E. et al. 1992. Winter cover crops influence insect populations in sustainable cantaloupe production. HortSci. 26:769.

56 Bugg, R. L. et al. 1990. Tarnished plant bug (Hemiptera miridae) on selected cool-season leguminous cover crops. J. Entomol. Sci. 25:463- 474.

57 Bugg, R. L. et al. 1991. Cool season cover crops relay intercropped with cantaloupe: Influence of a generalist predator, Geocoris punctipesJ. Econ. Entomol. 84:408-416.

58 Bugg, R. L. 1991. Cover crops and control of arthropod pests of agriculture. pp. 157-163. In W. L.Hargrove (ed.). Cover Crops for Clean Water. Soil and Water Conservation Society. Ankeny, Iowa.

59 Bugg, R. L. 1992. Using cover crops to manage arthropods on truck farms. HortSci. 27:741- 745.

60 Bugg, R. L. and C. Waddington. 1994. Using cover crops to manage arthropod pests of orchards: a review. Ag, Ecosystems & Env. 50: 11-28.

61 Bugg, R. L. 1995. Cover biology: a mini-review. SAREP Sustainable Agriculture-Technical Reviews. 7:4.Univ. of California, Davis, Calif.

62 Bugg, R. L. et al. 1996. Comparison of 32 cover crops in an organic vineyard on the north coast of California. Biol. Ag. and Hort. 13:63-81.

63 Bugg, R. L., R. J. Zomer and J. S. Auburn. 1996. Cover crop profiles: One-page summaries describing 33 cover crops. In Cover Crops: Resources for Education and Extension (Chaney, D. and A. D. Mayse, eds.). SAREP. Univ. of Calif., Division of Ag. and Natural Resources, Davis, Calif.

64 Bugg, R. L. and M. V. Horn. 1997. Ecological soil management and soil fauna : Best practices in California vineyards. Australian Society for Viticulture and Oenology, Inc. Proc. Viticulture Seminar, Mildura, Victoria, Australia.

65 Burgos, N. R. and R. E. Talbert. 1996. Weed control by spring cover crops and imazethapyr in no-till southern pea (Vigna unguiculata). Weed Tech. 10:893-899.

66 Burgos, N. R., R. E. Talbert and R. D. Mattice 1999. Cultivar and age differences in the production of allelochemicals by Secale cerealeWeed Sci. 47:481-485.

67 Buntin, G. D. et al. 1994. Cover crop and nitrogen fertility effects on southern corn rootworm (Coleoptera :Chrysomelidae) damage in corn. J. Econ. Entomol. 87:1683-1688.

68 Butler, L. M. 1996. Fall-planted cover crops in western Washington: a model for sustainability assessment. SARE Project Report #SW94-008. Western Region SARE. Logan, Utah.

69 Campbell, C. A. et al. 1993. Influence of legumes and fertilization of deep distribution of available phosphorus in a thin black chernozemic soil. Can. J. Soil Sci. 73:555-565.

70 Campbell, C. A. et al. 1993. Spring wheat yield trends as influenced by fertilizer and legumes. J. Prod. Ag. 6:564-568.

71 Canadian Organic Growers Inc. 1992. Organic Field Crop Handbook. Anne Macey (ed.). Canadian Organic Growers Inc., Ottawa, Ont.

72 CARR. P. Personal communication. 2007. North Dakota State Univ. Dickinson, ND.

73 Carr, P. M., W. P. Woodrow and L. J. Tisor. 2005. Natural reseeding by forage legumes following wheat in western North Dakota. Agron. J. 97:1270-1277.

74 Cash, D. et al. 1995. Growing Peas in Montana. Montguide MT 9520. Montana State Univ. Extension Service. Bozeman, Mont.

75 Cathey, H. M. 1990. USDA Plant Hardiness Zone Map. USDA-ARS Misc. Pub. No. 1475.

76 Chaney, D. and D. Mays. March 1997. Cover Crops: Resources for Education and Extension. UC SAREP, Division of Agriculture and Natural Resources, Davis Calif.

77 Cherr, C. M., J. M. S. Scholberg and R. McSorley. 2006. Green manure approaches to crop production: A synthesis. Agron. J. 98:302–319.

78 Chen, J., G. W. Bird. and R. L. Mather. 1995. Impact of multi-year cropping regimes on Solanum tuberosum tuber yields in the presence of Pratylenchus penetrans and Verticillium dahliaeJ. Nematol. 27:654-660.

79 Choi, B. H. et al. 1991. Acid amide, dinitroaniline, triazine, urea herbicide treatment and survival rate of coarse grain crop seedlings. Research Reports of the Rural Development Administration, Upland and Industrial Crops 3:33-42.

80 Clark, A. J. 2007. Personal communication. Sustainable Agriculture Network. USDA-SARE. Beltsville, MD.

81 Clark, A. J., A. M. Decker and J. J. Meisinger. 1994. Seeding rate and kill date effects on hairy vetch-cereal rye cover crop mixtures for corn production. Agron. J. 86:1065-1070.

82 Clark, A. J. et al. 1995. Hairy vetch kill date effects on soil water and corn production. Agron. J. 87:579-585.

83 Clark, A. J. et al. 1997a. Kill date of vetch, rye and a vetch-rye mixture: I. Cover crop and corn nitrogen. Agron. J. 89:427-434.

84 Clark, A. J. et al. 1997b. Kill date of vetch, rye and a vetch-rye mixture: II. Soil moisture and corn yield. Agron. J. 89:434-441.

85 Clark, A. J. et al. 2007a. Effects of a grass-selective herbicide in a vetch–rye cover crop system on corn grain yield and soil moisture. Agron. J. 99:43-48.

86 Clark, A. J. et al. 2007b. Effects of a grass-selective herbicide in a vetch–rye cover crop system on nitrogen management. Agron. J. 99:36-42.

87 Coale, F. J. et al. 2001. Small grain winter cover crops for conservation of residual soil nitrogen in the mid-Atlantic Coastal Plain. Amer. J. of Alt. Ag. 16:66-72.

88 Collins, H.P. et al. 2006. Soil microbial, fungal and nematode responses to soil fumigation and cover crops under potato production. Biol. Fert. Soils. 42:247-257.

89 Conservation Tillage Information Center. (2006).

90 Cooke, L. 1996. New Red Clover Puts Pastures in the Pink. USDA/ARS. 44:12 Washington, D.C.

91 Corak, S. J., W. W. Frye and M. S. Smith. 1991. Legume mulch and nitrogen fertilizer effects on soil water and corn production. Soil Sci. Soc. Am. J. 55(5):1395-1400.

92 Costa, J. M., G. A. Bollero and F. J. Coale. 2000. Early season nitrogen accumulation in winter wheat. J. Plant Nutrition 23:773-783.

93 Costello, M. J. 1994. Broccoli growth, yield and level of aphid infestation in leguminous living mulches. Biol. Ag. And Hort. 10:207-222.

94 Crawford, E. J. and B. G. Nankivell. Medics, general. Univ. of Calif. SAREP Cover Crops Resource Page.

95 Creamer, N. G. and S. M. Dabney. 2002.Killing cover crops mechanically: Review of recent literature and assessment of new research results. Amer. J. Alt. Ag. 17:32-40.

96 Creamer, N. G. et al. 1995. A method for mechanically killing cover crops to optimize weed suppression. Amer. J. Alt. Ag. 10:157-162.

97 Creamer, N. G. et al. 1996. A comparison of four processing tomato production systems differing in cover crop and chemical inputs. HortSci. 121:559-568.

98 Cruse, R. M. 1995. Potential economic, environmental benefits of narrow strip intercrop ping. Leopold Center Progress Reports 4:14-19.

99 Cunfer, B. M. 1997. Disease and insect management using new crop rotations for sustainable production of row crops in the Southern U. S. SARE Project Report #LS94-057. Southern Region SARE. Griffin, GA.

100 Curran W. S. et al. 1996. Cover Crops for Conservation Tillage Systems. Penn State Conservation Tillage Series, Number 5.

101 Dabney, S. 1996. Cover crop integration into conservation production systems. SARE Project Report #LS96-073. Southern Region SARE. Griffin, GA.

102 Dabney, S. M. 1995. Cover crops in reduced tillage systems. Proc. Beltwide Cotton Conferences. pp. 126-127. 5 Jan 1995. National Cotton Council, Memphis, Tenn.

103 Dabney, S. 2007. Personal communication. USDA /ARS. Oxford, Miss.

104 Dabney, S. M. and J. L. Griffin. 1987. Efficacy of burn down herbicides on winter legume cover crops. pp. 122-125. In Power, J. F. (ed.) The Role of Legumes in Conservation Tillage Systems. Soil and Water Conservation Society. Ankeny, Iowa.

105 Dabney, S. M. et al. 1991. Mechanical control of legume cover crops. pp. 146-147. In W. L. Hargrove (ed.). Cover Crops for Clean Water. Soil and Water Conservation Society. Ankeny, Iowa.

106 Dabney, S. M., J. A. Delgado and D. W. Reeves. 2001. Using winter cover crops to improve soil and water quality. Commun. Soil Plant Anal. 32:1221-1250.

107 Davis, D. W. et al. 1990. Cowpea. In Alternative Field Crops Manual. Univ. of Wisc-Ext. and Univ. of Minnesota. Madison, Wis. and St. Paul, Minn.

108 Decker, A. M. et al. 1994. Legume cover crop contributions to no-tillage corn production. Agron. J. 86:126-136.

109 Decker, A. M. et al. 1992. Winter Annual Cover Crops for Maryland Corn Production Systems. Agronomy Mimeo 34.Univ. of MD. Cooperative Ext. Service, MD. Inst. for Ag. and Natural Resources, College Park, MD.

110 DeGregorio, R. et al. 1995. Bigflower vetch and rye vs. rye alone as a cover crop for no-till sweetcorn. J. Sustain. Ag. 5:7-18.

111 Delgado, J. A. 1998. Sequential NLEAP simulations to examine effect of early and late planted winter cover crops on nitrogen dynamics. J. Soil Water Conserv. 53:241-244.

112 Delgado, J. A. and J. Lemunyon. 2006. Nutrient Management. pp. 1157-1160. In R. Lal (ed.). Encyclopedia Soil Sci. Markel and Decker, New York, pp 1924. NY.

113 Delgado, J. A. et al. 2007. Cover crops-potato rotations: Part III, making the connection- green manure cover crop effects on potato yield and quality. In Proceedings of the 25th Annual San Luis Valley Potato Grain Conference. Jan. 30–Feb. 2, 2007. Monte Vista, CO.

114 Delgado, J. A. et al.1999. Use of winter cover crops to conserve soil and water quality in the San Luis Valley of South Central Colorado. pp 125-142. In R. Lal (ed.). Soil Quality and Soil Erosion. CRC Press, Boca Raton, FL.

115 Delgado, J. A., W. Reeves and R. Follett. 2006. Winter Cover Crops. pp 1915-1917. In R Lal (ed.) Encyclopedia Soil Sci. Markel and Decker, New York, NY.

116 Doll, J. 1991.Cited in Shirley, C. D. No-till beans: rye not?! The New Farm. 13:12-15.

117 Doll, J. and T. Bauer. 1991. Rye: more than a mulch for weed control. pp. 146-149. Illinois Agricultural Pesticides Conference presentation summaries.Urbana, Ill.

118 Duiker, S. W. and W. S. Curran. 2005. Rye cover crop management for corn production in the northern Mid-Atlantic region. Agron. J. 97:1413- 1418.

119 Duiker, S. J. and J. Myers. 2005. Better Soils with the No-till System

120 Duke, J. A. 1981. Handbook of Legumes of World Economic Importance. Plenum Press, N.Y.

121 Earhart, D. R. 1996. Managing soil phosphorus accumulation from poultry litter application through vegetable/legume rotations. Project Report #LS95-69. Southern Region SARE. Griffin, GA.

122 Eberlein, C. 1995. Development of winter wheat cover crop systems for weed control in potatoes. SARE Project Report #LW91-027. Western Region SARE. Logan, Utah.

123 Eckert, D. J. 1991. Chemical attributes of soils subjected to no-till cropping with rye cover crops. Soil Sci. Soc. Am. J. 55:405-409.

124 Edwards, W. M. et al. 1993.Tillage studies with a corn-soybean rotation:Hydrology and sediment loss. Soil Sci. Soc. Am. J. 57:1051-1055.

125 Einhellig, F. A. and J. A. Rasmussen. 1989. Prior cropping with grain sorghum inhibits weeds. J. Chem. Ecol. 15:951-960.

126 Einhellig, F. A. and I. F. Souze. 1992. Allelopathic activity of sorgoleone. J. Chem. Ecol. 18:1-11.

127 Enache, A. J., R. D. Ilnicki and R. R. Helberg. 1992. Subterranean clover living mulch: a system approach. pp. 160-162. In Proc. First Int’l Weed Control Congress, Vol. 2. February 17- 21, 1992. Weed Science Society of Victoria, Melbourne, Australia.

128 Enache, A. J. 1990. Weed control by subterranean clover (Trifolium subterraneum L.) used as a living mulch. Dissertation Abstracts Int., Sci. and Eng., 1990, 50(11):4825B.

129 Entz, M. H. et al. 2002. Potential of forages to diversify cropping systems in the Northern Great Plains. Agron. J. 94:240-250.

130 Evers, G.W and G. R. Smith. 2006. Crimson clover seed production and volunteer reseeding at various grazing termination dates. Agron. J. 98:1410-1415.

131 Evers, G. W., G. R. Smith and P. E. Beale. 1988. Subterranean clover reseeding. Agron. J. 80:855- 859.

132 Evers, G. W., G. R. Smith and C. S. Hoveland. 1997. Ecology and production of annual ryegrass. pp. 29-43. In F. M. Rouquette, Jr. and L. R. Nelson (eds.). Production and management of Lolium for forage in the USA. CSSA Spec. Pub. #24. ASa, CSSA, SSA. Madison, Wisc.

133 Fairbrother, T. E. 1991. Effect of fluctuating temperatures and humidity on the softening rate of hard seed of subterranean clover (Trifolium subterraneum L.). Seed Sci. Tech. 19:93-105.

134 Fairbrother, T. E. 1997. Softening and loss of subterranean clover hard seed under sod and bare ground environments. Crop. Sci. 37:839-844.

135 Farahani H. J., G. A. Peterson and D. G. Westfall. 1998. Dryland cropping intensification: a fundamental solution to efficient use of precipitation. Adv. Agron. 64:197-223.

136 Fasching, R. 2006. Personal communication. Bozeman, Mont.

137 Feng, Y. et al. 2003. Soil microbial communities under conventional-till and no-till continuous cotton systems. Soil Biol. Biochem. 35(12):1693- 1703.

138 Finch, C. U. Univ. of Calif. Medics, general. SAREP Cover Crops Resource Page.

139 Fischer, A. and L. Burrill. 1993.Managing interference in sweet corn-white clover living mulch system. Am. J. Alt. Ag. 8:51-56.

140 Fisk, J. W. and O.B. Hesterman. 1996. N contribution by annual legume cover crops for no-till corn. In 1996 Cover Crops Symposium Proceedings. Michigan State Univ., W. K. Kellogg Biological Station, Battle Creek, Mich.

141 Fisk, J. W. et al. 2001. Weed suppression by annual legume cover crops in no-tillage corn. Agron. J. 93:319-325.

142 Flexner, J. L. 1990. Hairy vetch. Univ. of Calif. SAREP Cover Crops Resource Page.

143 Folorunso, O. et al. 1992. Cover crops lower soil surface strength, may improve soil permeability. Calif. Ag. 46:26-27.

144 Forney, D. R. and L. F. Chester. 1984. Phytotoxicity of products from rhizospheres of a sorghum-sudangrass hybrid. Weed Sci. 33:597- 604.

145 Forney, D. R. et al. 1985. Weed suppression in no-till alfalfa (Medicago sativa) by prior cropping of summer-annual forage grasses. Weed Sci. 33:490-497.

146 Fortin, M. C. and A S. Hamill. 1994.Rye residue geometry for faster corn development. Agron. J. 86:238-243.

147 Foster, R. K. 1990. Effect of tillage implement and date of sweetclover incorporation on available soil N and succeeding spring wheat yields. Can. J. Plant Sci. 70:269-277.

148 Fox, R. H. and W. P. Piekielek. 1988. Fertilizer N equivalence of alfalfa, birdsfoot trefoil, and red clover for succeeding corn crops. J. Prod. Agric. 1:313-317.

149 Friedman, D. et al. 1996. Evaluation of five cover crop species or mixes for nitrogen production and weed suppression in Sacramento Valley farming systems. Univ. of California Cover Crop Research and Education Summaries. 1994–1996.Davis, Calif.

150 Friesen, G. H. 1979. Weed interference in transplanted tomatoes (Lycopersicon esculentum). Weed Sci. 27:11-13.

151 Frye W. W., W. G. Smith and R. J. Williams. 1985. Economics of winter cover crops as a source of nitrogen for no-till corn. J. Soil Water Conserv. 40:246–249.

152 Gardiner, J.B. et al. 1999. Allelochemicals released in soil following incorporation of rapeseed (Brassica napus) green manures. J. Agric. Food Chem. 47:3837-3842.

153 Gardner, J. (ed.). 1992. Substituting legumes for fallow in U. S. Great Plains wheat production: The first five years of research and demonstration 1988-1992. USDA/SARE and North Dakota State Univ., Michael Fields Agricultural Institute, Kansas State Univ. and Univ. of Nebraska. NDSU Carrington Research Extension Center, Carrington, N. D.

154 Geneve, R. L. and L. A. Weston. 1988.Growth reduction of Eastern redbud (Cercis canadensis L.) seedlings caused by interaction with a sorghum-Sudangrass hybrid (Sudax). J. Env. Hort. 6:24-26.

155 Ghaffarzadeh, M. 1994. Progress Report: Berseem Clover (Trifolium alexandrinum L.). 17 pp. Soil Management, Agronomy Department, Iowa State Univ., Ames, Iowa.

156 Ghaffarzadeh, M. 1995. Considering annual clover? Don’t overlook berseem. Pub. #SA-7. 4 pp. Sustainable Agriculture Fact Sheet Series. The Leopold Center, Ames, Iowa.

157 Ghaffarzadeh, M. 1996. Forage-based beef production research at the Armstrong Outlying Research farm. Annual research report. A. S. Leaflet R1245. Iowa State Univ., Ames, Iowa.

158 Ghaffarzadeh, M. 1997. Annual legume makes comeback. pp. 24-25. Beef Today. January, 1997.

159 Ghaffarzadeh, M. 1997. Economic and biological benefits of intercropping berseem clover with oat in corn-soybean-oat rotations. J. Prod. Ag. 10:314-319.

160 Ghaffarzadeh, M. 1995. Potential uses of annual berseem clover in livestock production. Proc. Rotational Grazing, a conference sponsored by The Leopold Center for Sustainable Agriculture, Feb. 5-6, 1995. Published by Iowa State Univ. Extension. See also Demonstration of an annual forage crop integrated with crop and livestock enterprises. In Progress Report. March 1998. The Leopold Center for Sustainable Agriculture 7:6-10.

161 Gill, G. S. 1995. Development of herbicide resistance in annual ryegrass populations (Lolium rigidum Gaud.) in the cropping belt of Western Australia. Austral. J. of Exp. Ag. 35:67-72.

162 Graves, W. L. et al. 1996. Berseem Clover: a Winter Annual Forage for California Agriculture. Univ. of California, SAREP. Div. of Agriculture and Natural Resources. Pub. 21536. Davis, Calif.

163 Green, B. J. and V. O. Biederbeck. 1995. Farm Facts: Soil Improvement with Legumes, Including Legumes in Crop Rotations. Canada - Saskatchewan Agreement on Soil Conservation, Regina, SK.

164 Greene, D.K. et al.1992.Research report. New Crop News. Vol. 3. Purdue Univ., West Lafayette, Ind.

165 Griffin, J. L. and S. M. Dabney. 1990. Preplant postemergence herbicides for legume cover-crop control in minimum tillage systems. Weed Tech. 4:332-336.

166 Griffin, T. 2007. Personal communication. USDA Agricultural Research Service, Orono, Maine.

167 Griffith, K and J. Posner. 2001. Comparing Upper Midwest farming systems: Results from the first 10 years of the Wisconsin Integrated Cropping Systems Trial (WICST). Univ of Wisconsin, Center for Integrated Agricultural Systems. 

168 Grinsted M. J. et al. 1982. Plant-induced changes in the rhizosphere of rape (Brassica napus var. Emerald) seedlings. I. pH change and the increase in P concentration in the soil solution. New Phytol. 91:19.

169 Groff, Steve. 1997. Cedar Grove Farm.

170 Grubinger, V. P. and P. L. Minotti. 1990. Managing white clover living mulch for sweet corn production with partial rototilling. Amer. J. Alt. Ag. 5:4-11.

171 Halvorson, A. D. et al. 2006. Nitrogen and tillage effects on irrigated continuous corn yields. Agron. J. 98:63–71.

172 Halvorson, A. D. and C. A. Reule. 2006. Irrigated corn and soybean response to nitrogen under no-till in northern Colorado. Agron. J. 98:1367–1374.

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174 Hanson, J.C. et al. 1997. Organic versus conventional grain production in the mid-Atlantic: An economic and farming system overview. Amer. J. Alt. Ag. 12:2-9.

175 Hao, J. J and K. V. Subbarao. 2006. Dynamics of lettuce drop incidence and Sclerotinia minor inoculum under varied crop rotations. Plant Dis. 90:269-278.

176 Haramoto, E. R. and E. R. Gallandt. 2004. Brassica cover cropping for weed management: a review. Renewable Ag. and Food Sys. 19:187-198.

177 Haramoto, E. R. and E. R.Gallandt. 2005. Brassica cover cropping: I. Effects on weed and crop establishment. Weed Sci. 53:695-701.

178 Haramoto, E. R. and E. R.Gallandt. 2005. Brassica cover cropping: II. Effects on growth and interference of green bean (Phaseolus vulgaris) and redroot pigweed (Amaranthus retroflexus). Weed Sci. 53:702-708.

179 Haramoto, E. R. and E. R. Gallandt. 2005. Brassica cover cropping: II. Effects on growth and interference of green bean (Phaseolus vulgaris) and redroot pigweed (Amaranthus retroflexus). Weed Sci. 702-708.

180 Harlow, S. 1994. Cover crops pack plenty of value. Amer. Agriculturalist 191:14.

181 Harper, L. A. et al. 1995. Clover management to provide optimum nitrogen and soil water conservation. Crop Sci. 35:176-182.

182 Hartwig, N. L. and H. U. Ammon. 2002. Cover crops and living mulches. Weed Sci. 50:688-699.

183 Helm, J. L. and D. Meyer. 1993. Sweetclover production and management. North Dakota Extension Service Publication R-862. Fargo, N. D.

184 Hendricks L. C. 1995.Almond growers reduce pesticide use in Merced County field trial. Calif. Ag. 49:5-10.

185 Hendrix, P. F. et al. 1986. Detritus food webs in conventional and no-tillage agroecosystems. Bioscience 36:374-380.

186 Hermel, R. 1997. Forage Focus: Annual legume makes comeback. pp. 24-25. Beef. January, 1997.

187 Herrero, E. V. et al. 2001. Use of cover crop mulches in a no-till furrow-irrigated processing tomato production system. HortTech. 11:43-48.

188 Hiltbold, A. E. 1991. Nitrogen-fixing bacteria essential for crimson clover. Alabama Agricultural Experiment Station 38:13. Auburn, Ala.

189 Hoffman, M. L. et al. 1993. Weed and corn responses to a hairy vetch cover crop. Weed Tech. 7:594-599.

190 Hoffman, M. L. et al. 1996. Interference mechanisms between germinating seeds and between seedlings: Bioassays using cover crop and weed species. Seed Sci. 44:579-584.

191 Hofstetter, B. 1988. The New Farm’s cover crop guide: 53 legumes, grasses and legume-grass mixes you can use to save soil and money. The New Farm 10:17-22, 27-31.

192 Hofstetter, B. 1992. Bank on buckwheat. The New Farm 14:52-53.

193 Hofstetter, B. 1992. How sweet it is: Yellow-blossom sweetclover fights weeds, adds N and feeds livestock. The New Farm 14:6-8.

194 Hofstetter, B. 1992. Reliable ryegrass. The New Farm 14:54-55, 62.

195 Hofstetter, B. 1993a. Meet the queen of cover crops. The New Farm 15:37-41.

196 Hofstetter, B. 1993b. Fast and furious. The New Farm 15:21-23, 46.

197 Hofstetter, B. 1993c. Red clover revival. The New Farm 15:28-30.

198 Hofstetter, B. 1993d. A quick & easy cover crop. The New Farm 15:27-28.

199 Hofstetter, B. 1993e. Reconsider the lupin. The New Farm 15:48-51.

200 Hofstetter, B. 1994a. The carefree cover. The New Farm 16:22-23.

201 Hofstetter, B. 1994b. Bring on the medics! The New Farm 16:56, 62.

202 Hofstetter, B. 1994c.Warming up to winter peas. The New Farm 16:11-13.

203 Hofstetter, B. 1995.Keep your covers in the pink. The New Farm 17:8-9.

204 Holderbaum, J. F. et al. 1990. Fall-seeded legume cover crops for no-tillage corn in the humid East. Agron. J. 82:117-125.

205 Holle, O. 1995. Compare the agronomic and economic benefits of 3 or 4 annual alfalfa varieties to sweetclover for forage and soil building purposes in a feed grain, soybeans, wheat / legume rotation. SARE Project Report #FNC92-004.North Central Region SARE. St. Paul, Minn.

206 House, G. J and Alzugaray, M. D. R. 1989. Hairy vetch. Univ. of Calif. SAREP Cover Crops Resource Page.

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209 Hutchinson, C. M. and M. E. McGiffen. 2000. Cowpea cover crop mulch for weed control in desert pepper production. HortSci. 35:196-198.

210 Ingels, C. A. et al. 1994. Selecting the right cover crop gives multiple benefits. Calif. Ag. 48:43-48.

211 Ingels, C. A. 1995. Cover cropping in vineyards. Amer. Vineyard. 6/95, 8/95, 9/95, 10/95. In Chaney, David and Ann D. Mayse (eds.). 1997. Cover Crops:Resources for Education and Extension. Univ. of California, Div. of Agriculture and Natural Resources, Davis, Calif.

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213 Ingham, R. E. et al.1994. Control of Meloidogyne chitwoodi with crop rotation, green manure crops and nonfumigant nematicides. J. Nematol. 26:553.

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215 Izaurralde, R.C. et al. 1990. Plant and nitrogen yield of barley-field pea intercrop in cryoboreal-subhumid central Alberta. Agron. J. 82:295-301.

216 Jackson, L. E. 1995. Cover crops incorporated with reduced tillage on semi-permanent beds: Impacts on nitrate leaching, soil fertility, pests and farm profitability. SARE Project Report #AW92-006.Western Region SARE. Logan, Utah.

217 Jacobs, E. 1995. Cover crop breathes life into old soil: Sorghum-sudangrass, used as an onion rotation crop on organic soils, cuts pesticide costs, rejuvenates soil and increases yields. Amer. Agriculturist 192:8.

218 Jensen, E. S. 1996. Barley uptake of N deposited in the rhizosphere of associated field pea. Soil. Biol. Biochem. 28:159-168.

219 Jeranyama, P., O. B. Hesterman and C. C. Sheaffer. 1998. Medic planting date effect on dry matter and nitrogen accumulation when clearseeded or intercropped with corn. Agron. J. 90:616-622.

220 Jordan, J. L. et al. 1994. An Economic Analysis of Cover Crop Use in Georgia to Protect Groundwater Quality. Research Bulletin #419.Univ. of Georgia, College of Agric. and Environ. Sciences, Athens, GA. 13 pp.

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222 Kandel, H. J., B. L. Johnson and A. A. Schneiter. 2000. Hard red spring wheat response following the intercropping of legumes into sunflower. Crop Sci. 40:731-736.

223 Kaspar, T. C., J. K. Radke and J. M. Laflen. 2001. Small grain cover crops and wheel traffic effects on infiltration, runoff, and erosion. J. Soil Water Conserv. 56:160-164.

224 Kelly, T. C. et al. 1995. Economics of a hairy vetch mulch system for producing fresh-market tomatoes in the Mid-Atlantic region. HortSci. 120:854-869.

225 Kimbrough, E., L. and W. E. Knight. Forage ‘Bigbee’ Berseem Clover. Mississippi State Univ. Extension Service.

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227 Kirchmann, H. and H. Marstop. 1992. Calculation of N mineralization from six green manure legumes under field conditions from autumn to spring. Acta Agriculturae Scand. 41:253- 258.

228 Knight, W. E. 1985. Crimson clover. Univ. of Calif. SAREP Cover Crops Resource Page.

229 Knorek, J. and M. Staton. 1996. “Red Clover.” Cover Crops: MSU/KBS (fact sheet packet), Michigan State Univ. Extension, East Lansing, Mich.

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231 Koch, D. W. 1995. Brassica utilization in sugarbeet rotations for biological control of cyst nematode. SARE Project Report #LW91-022. Western Region SARE. Logan, Utah.

232 Koike, S.T. et al. 1996. Phacelia, Lana woollypod vetch and Austrian winter pea : three new cover crop hosts of Sclerotina minor in California. Plant Dis. 80:1409-1412.

233 Koume, C. N. et al. 1988. Screening subterranean clover (Trifolium spp.) germplasm for resistance to Meloidogyne species. J. Nematol. 21(3):379-383.

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239 Lanini, W. T. et al. 1989. Subclovers as living mulches for managing weeds in vegetables. Calif. Agric. 43:25-27. Larkin, R.P. See #458, 459, 460.

240 Leach, S. S. 1993. Effects of moldboard plowing, chisel plowing and rotation crops on the Rhizoctonia disease of white potato. Amer. Potato J. 70:329-337.

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254 Mahler, R. L. 1993. Evaluation of the nitrogen fertilizer value of plant materials to spring wheat production. Agron J. 85:305-309.

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265 Meisinger, J. J. et al.1991. Effects of cover crops on groundwater quality. pp. 57-68. In W. L. Hargrove (ed.). Cover Crops for Clean Water. Soil and Water Conservation Society. Ankeny, Iowa.

266 Melakeberhan, H. et al. 2006. Potential use of arugula (Eruca sativa L.) as a trap crop for Meloidogyne haplaNematol. 8: 793-799.

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270 Michigan State Univ. Extension. Cover Crops Program. East Lansing, Mich.

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272 Miller, M. M. 7/21/97. Reduced input, diversified systems. Press release via electronic transmission from Univ. of Wisconsin Extension-Agronomy, Madison, Wis.

273 Miller, P. R. et al. 1989. Cover Crops for California Agriculture. Univ of California, SAREP. Div. of Agriculture and Natural Resources. Davis, Calif. 24 pp.

274 Miller, M. H. et al. 1994. Leaching of nitrogen and phosphorus from the biomass of three cover crops. J. Environ. Qual. 23:267-272.

275 Miller, P. R. 1989. Medics, general. Univ. of Calif. SAREP Cover Crops Resource Page.

276 Millhollon, E. P. 1994.Winter cover crops improve cotton production and soil fertility in Northwest Louisiana. La. Ag. 37:26-27.

277 Mishanec, J. 1996. Use of sorghum sudangrass for improved yield and quality of vegetables produced on mineral and muck soils in New York: Part II—Sudan trials on muck soils in Orange County. Research report. Cornell Cooperative Extension. Ithaca, N.Y.

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