Skip to main content Accessibility help

Cover Crop Impact on Weed Dynamics in an Organic Dry Bean System

  • Erin C. Hill (a1), Karen A. Renner (a1), Christy L. Sprague (a1) and Adam S. Davis (a2)


Weed suppression is one possible benefit of including cover crops in crop rotations. The late spring planting date of dry beans allows for more growth of cover crops in the spring. We assessed the influence of cover crops on weed dynamics in organic dry beans and weed seed persistence. Medium red clover, oilseed radish, and cereal rye were planted the year before dry beans; a no-cover-crop control was also included. After cover-crop incorporation, common lambsquarters, giant foxtail, and velvetleaf seeds were buried in the red clover, cereal rye, and no-cover control treatments and then retrieved 0, 1, 2, 4, 6, and 12 mo after cover-crop incorporation. Dry beans were planted in June and weed emergence and biomass measured. Eleven or more site-years of data were collected for each cover-crop treatment between 2011 and 2013, allowing for structural equation modeling (SEM), in addition to traditional analyses. Cereal rye residue increased giant foxtail and velvetleaf seed persistence by up to 12%; red clover decreased common lambsquarters seed persistence by 22% in 1 of 2 yr relative to the no-cover-crop control. Oilseed radish and incorporated cereal rye rarely reduced weed densities. When red clover biomass exceeded 5 Mg ha−1, soil inorganic N was often higher (5 of 6 site-years), as were weed density and biomass (5 and 4 of 12 main site sample times, respectively). Using SEM, we identified one causal relationship between cover-crop N content and weed biomass at the first flower stage (R1), as mediated through soil N at the time of dry bean planting and at the stage with two fully expanded trifoliates. Increasing cover-crop C : N ratios directly reduced weed biomass at R1, not mediated through changes in soil N. Cover crops that make a significant contribution to soil N may also stimulate weed emergence and growth.


Corresponding author

Corresponding author's E-mail:


Hide All
Anderson, RL, Tanaka, DL, Black, AL, Schweizer, EE (1998) Weed community and species response to crop rotation, tillage, and nitrogen fertility. Weed Technol 12:531536
Bárberi, P, Mazzoncini, M (2001) Changes in weed community composition as influenced by cover crop and management system in continuous corn. Weed Sci 49:491499
Blackshaw, RE, Brandt, RN, Janzen, HH, Entz, T, Grant, CA, Derksen, DA (2003) Differential response of weed species to added nitrogen. Weed Sci 51:532539
Blackshaw, RE, Molnar, LJ, Janzen, HH (2004) Nitrogen fertilizer timing and application method affect weed growth and competition with spring wheat. Weed Sci 52:614622
Blackshaw, RE, Moyer, JR, Doram, RC, Boswell, AL (2001) Yellow sweetclover, green manure, and its residues effectively suppress weeds during fallow. Weed Sci 49:406413
Blum, U, King, LD, Gerig, TM, Lehman, ME, Worsham, AD (1997) Effects of clover and small grain cover crops and tillage techniques on seedling emergence of some dicotyledonous weed species. Am J Alternative Agric 12:146161
Brennan, EB, Smith, RF (2005) Winter cover crop growth and weed suppression on the central coast of California. Weed Technol 19:10171024
Buhler, DD (1997) Effects of tillage and light environment on emergence of 13 annual weeds. Weed Technol 11:496501
Cardina, J, Sparrow, DH (1997) Temporal changes in velvetleaf (Abutilon theophrasti) seed dormancy. Weed Sci 45:6166
Chung, YR, Hoitink, HAH, Lipps, PE (1988) Interactions between organic matter decomposition level and soilborne disease. Agric Ecosyst Environ 24:183193
Clark, A (2007) Managing cover crops profitably. 3rd edn. Beltsville, MD Sustainable Agriculture Network. 244 p
Clark, AJ, Decker, AM, Meisinger, JJ, McIntosh, MS (1997) Kill date of vetch, rye, and a vetch–rye mixture: I. Cover crops and corn nitrogen. Agron J 89:427434
Conklin, AE, Erich, MS, Liebman, M, Lambert, D, Gallandt, ER, Halteman, WA (2002) Effects of red clover (Trifolium pretense) green manure and compost soil amendments on wild mustard (Brassica kaber) growth and incidence of disease. Plant Soil 238:245256
Creamer, NG, Baldwin, KR (2000) An evaluation of summer cover crops for use in vegetable production systems in North Carolina. HortScience 35:600603
Creamer, NG, Bennett, MA, Stinner, BR, Cardina, J (1996) A comparison of four processing tomato production systems differing in cover crop and chemical inputs. J Am Soc Hortic Sci 121:559568
[CTIC, NCR-SARE] Conservation Technology Information Center and U.S. Department of Agriculture North Central Region Sustainable Agriculture Research and Education (2013) 2012-2013 Cover crop survey. Accessed July 12, 2014
Davis, AS (2007) Nitrogen fertilizer and crop residue effects on seed mortality and germination of eight annual weed species. Weed Sci 55:123128
Davis, AS, Anderson, KI, Hallett, SG, Renner, KA (2006) Weed seed mortality in soils with contrasting agricultural management histories. Weed Sci 54:291297
Davis, AS, Cardina, J, Forcella, F, Johnson, GA, Kegode, G, Lindquist, JL, Luschei, EC, Renner, KA, Sprague, CL, Williams, MM II (2005) Environmental factors affecting seed persistence of annual weeds across the U.S. corn belt. Weed Sci 53:860868
Davis, AS, Liebman, M (2003) Cropping system effects on giant foxtail (Setaria faberi) demography: I. Green manure and tillage timing. Weed Sci 51:919929
De Cauwer, B, D'Hose, T, Cougnon, M, Leroy, B, Bulcke, R, Reheul, D (2011) Impact of the quality of organic amendments on size and composition of the weed seed bank. Weed Res 51:250260
Dyck, E, Liebman, M (1994) Soil fertility management as a factor in weed control: the effect of crimson clover residue, synthetic nitrogen fertilizer, and their interaction on emergence and early growth of lambsquarters and sweet corn. Plant Soil 167:227237
Fawcett, RS, Slife, FW (1978) Effects of field applications of nitrate on weed seed germination and dormancy. Weed Sci 26:594596
Fennimore, SA, Jackson, LE (2003) Organic amendment and tillage effects on vegetable field weed emergence and seedbanks. Weed Technol 17:4250
Fisk, JW, Hesterman, OB, Shrestha, A, Kells, JJ, Harwood, RR, Squire, JM, Sheaffer, CC (2001) Weed suppression by annual legume cover crops in no-tillage corn. Agron J 93:319325
Forcella, F (1992) Prediction of weed seedling from buried seed reserves. Weed Res 32:2938
Gallandt, ER (2006) How can we target the weed seedbank? Weed Sci 54:588596
Grace, JB (2006) Structural equation modeling and natural systems. Cambridge, UK Cambridge University Press. 365 p
Grace, JB, Anderson, TM, Olff, H, Scheiner, SM (2010) On the specification of structural equation models for ecological systems. Ecol Monogr 80:6787
Gross, K (1990) A comparison of methods for estimating seed numbers in the soil. J Ecol 78:10791093
Heggenstaller, AH, Liebman, M (2006) Demography of Abutilon theophrasti and Setaria faberi in three crop rotation systems. Weed Res 46:138151
Henson, IE (1970) The effects of light, potassium nitrate, and temperature on the germination of Chenopodium album L. Weed Res 10:2739
Hill, EC (2006) Allelopathic Effects of Hairy Vetch (Vicia villosa) and Cowpea (Vigna unguiculata) on Weeds and Vegetable Crops. . East Lansing, MI Michigan State University. 119 p
Hill, EC, Renner, KA, Sprague, CL (2014) Henbit (Lamium amplexicaule), common chickweed (Stellaria media), shepherd's-purse (Capsella bursa-pastoris), and field pennycress (Thlaspi arvense): fecundity, seed dispersal, dormancy, and emergence. Weed Sci 62:97106
Hill, EC, Renner, KA, Sprague, CL (2016) Cover crop impact on nitrogen availability and dry bean in an organic system. Agron J 108:329341
Kane, DA, Snapp, SS, Davis, AS (2015) Ridge tillage concentrates potential mineralizable soil nitrogen, facilitating maize uptake. Soil Sci Soc Am J 79:8188
Kegode, GO, Pearce, RB (1998) Influence of environment during maternal plant growth on dormancy of shattercane (Sorghum bicolor) and giant foxtail (Setaria faberi) seed. Weed Sci 46:322329
Kelton, J, Price, AJ, Mosjidis, J (2012) Allelopathic weed suppression through the use of cover crops. Pages 115130 in Price, A, ed. Weed Control. Shanghai, China InTech China
Kremer, RJ (1993) Management of weed seed banks with microorganisms. Ecol Appl 3:4252
Kruidhof, HM, Bastiaans, L, Kropff, MJ (2008) Ecological weed management by cover cropping: effects on weed growth in autumn and weed establishment in spring. Weed Res 48:492502
Kruidhof, HM, Bastiaans, L, Kropff, MJ (2009) Cover crop residue management for optimizing weed control. Plant Soil 318:169184
Kuo, S, Jellum, EJ (2002) Influence of cover crop and residue management on soil nitrogen availability and corn. Agron J 94:501508
Laflen, JM, Amemiya, M, Hintz, EA (1981) Measuring crop residue cover. J Soil Water Conserv 36:341343
Lamb, EG, Shirtliffe, SJ, May, WE (2011) Structural equation modeling in the plant sciences: an example using yield components in oat. Can J Plant Sci 91:603619
Lawley, YE, Teasdale, JR, Weil, RR (2012) The mechanism for weed suppression by a forage radish cover crop. Agron J 104:110
Machado, S (2007) Allelopathic potential of various plant species on downy brome: Implications for weed control in wheat production. Agron J 99:127132
Manici, LM, Caputo, F, Babini, V (2004) Effect of green manure on Pythium spp. population and microbial communities in intensive cropping systems. Plant Soil 263:133142
McDaniel, MD, Tiemann, LK, Grandy, AS (2014) Does agricultural crop diversity enhance soil microbial biomass and organic matter dynamics? A meta-analysis. Ecol Appl 24:560570
McLeod, EM, Banerjee, S, Bork, EW, Hall, LM, Hare, DD (2015) Structural equation modeling reveals complex relationships in mixed forage swards. Crop Prot 78:106113
Mendes, IC, Banki, AK, Dick, RP, Bottomley, PJ (1999) Microbial biomass and activities in soil aggregates affected by winter cover crops. Soil Sci Soc Am 4:878881
[MI Climatologist] Michigan State Climatologist's Office (2014) Climate statistics: Normals and statistics. Accessed September 30, 2014
Mirsky, SB, Gallandt, ER, Mortensen, DA, Curran, WS, Shumway, DL (2010) Reducing the germinable weed seedbank with soil disturbance and cover crops. Weed Res 50:341352
Mohler, CL, Dykeman, C, Nelson, EB, DiTommaso, A (2012) Reduction in weed seedling emergence by pathogens following the incorporation of green crop residue. Weed Res 52:467477
[MSU Enviroweather] Michigan State University Enviro-weather (2014) Weather station network. Accessed September 30, 2014
Mulvaney, RL (1996) Nitrogen—inorganic forms. Pages 11231184 in Sparks, DL, ed. Methods of Soil Analysis. Part 3, Chemical Methods Book Series 5. Madison, WI Soil Science Society of America
Ohno, T, Doolan, K, Zibilske, LM, Liebman, M, Gallandt, ER, Berube, C (1999) Phytotoxic effects of red clover amended soils on wild mustard seedling growth. Agric Ecosyst Environ 78:187192
O'Reilly, KA, Robinson, DE, Vyn, RJ, Van Eerd, LL (2011) Weed populations, sweet corn yield, and economics following fall cover crops. Weed Technol 25:374384
Park, SJ, Buttery, BR (1992) Ethyl-methane sulphonate (EMS) induced nodulation mutants of common bean (Phaseolus vulgaris L.) lacking effective nodules. Plant Soil 139:295298
Peachey, RE, William, RD, Mallory-Smith, C (2004) Effect of no-till or conventional planting and cover crops residues on weed emergence in vegetable row crop. Weed Technol 18:10231030
Peters, J (2000) Tetrazolium Testing Handbook. Contrib. No. 29 to the Handbook on Seed Testing. Lincoln, NE, Association of Official Seed Analysts. 32 p
Putnam, AR (1988) Allelochemicals from plants as herbicides. Weed Technol 2:510518
R Development Core Team (2015) R: a language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. Accessed July 7, 2015
Reddy, KN (2001) Effects of cereal and legume cover crop residues on weeds, yield, and net return in soybean (Glycine max ). Weed Technol 15:660668
Reddy, KN, Zablotowicz, RM, Locke, MA, Koger, CH (2003) Cover crop, tillage, and herbicide effects on weeds, soil properties, microbial populations, and soybean yield. Weed Sci 51:987994
Rice, CP, Cai, G, Teasdale, JR (2012) Concentrations and allelopathic effects of benzoxazinoid compounds in soil treated with rye (Secale cereal) cover crop. J Agric Food Chem 60:44714479
Rosseel, Y (2012) lavaan: an R package for structural equation modeling. J Stat Softw 48:136
Rosseel, Y (2013) The lavaan tutorial. Accessed July 7, 2015
Ross, SM, Ling, JR, Izaurralde, C, O'Donovan, JT (2001) Weed suppression by seven clover species. Agron J 93:820827
Sandler, L, Nelson, KA, Dudenhoeffer, CJ (2015) Radish planting date and nitrogen rate for cover crop production and the impact on corn yields in upstate Missouri. J Agric Sci (Toronto) 7:113
Sawhney, R, Naylor, JM (1982) Dormancy studies in seed of Avena fatua. 13. Influence of drought stress during seed development on duration of seed dormancy. Can J Bot 60:10161020
Schomberg, HH, Endale, DM, Calegari, A, Peixoto, R, Miyazawa, M, Cabrera, ML (2006) Influence of cover crops on potential nitrogen availability to succeeding crops in a Southern Piedmont soil. Biol Fertil Soils 42:229307
Schreiber, MM, Orwick, PL (1978) Influence of nitrogen fertility on growth of foxtail (Setaria) taxa. Weed Sci 26:547550
Schutte, BJ, Davis, AS, Renner, KA, Cardina, J (2008) Maternal and burial environment effects on seed mortality of velvetleaf (Abutilon theophrasti) and giant foxtail (Setaria faberi ). Weed Sci 56:834840
Shem-Tov, S, Klose, S, Ajwa, S, Fennimore, SA (2005) Effect of soil carbon: nitrogen ratio and organic matter amendments on seedbank longevity. Weed Sci Soc Am 45:324[Abstract]
Smith, RG, Davis, AS, Jordan, NR, Atwood, LW, Daly, AB, Grandy, AS, Hunter, MC, Koide, RT, Mortensen, DA, Ewing, P, Kane, D, Li, M, Lou, Y, Snapp, SS, Spokas, KA, Yannarell, AC (2014) Structural equation modeling facilitates transdisciplinary research on agriculture and climate change. Crop Sci 54:475483
Snapp, SS, Swinton, SM, Labarta, R, Mutch, D, Black, JR, Leep, R, Nyiraneza, J, O'Neil, K (2005) Evaluating cover crops for benefits, costs and performance within cropping system niches. Agron J 97:322332
Stivers-Young, L (1998) Growth, nitrogen accumulation, and weed suppression by fall cover crops following early harvest of vegetables. HortScience 33:6063
Sweeney, AE, Renner, KA, Laboski, C, Davis, A (2008) Effect of fertilizer nitrogen on weed emergence and growth. Weed Sci 56:714721
Teasdale, JR (1996) Contribution of cover crops to weed management in sustainable agricultural systems. J Prod Agric 9:475479
Teasdale, JR (1998) Cover crops, smother plants, and weed management. Pages 247270 in Hatfield, JL, Buhler, DD, Stewart, BA, eds. Integrated Weed and Soil Management. Chelsea, MI Ann Arbor Press
Teasdale, JR, Brandsaeter, LO, Calegari, A, Skora Neto, F (2007) Cover crops and weed management. Pages 4964 in Upadhyaya, MK, Blackshaw, RE, eds. Nonchemical Weed Management: Principles, Concepts and Technology. Reading, UK Biddles Ltd
Teasdale, JR, Rice, CP, Cai, C, Mangum, RW (2012) Expression of allelopathy in the soil environment: soil concentration and activity of benzoxazinoid compounds released by rye cover crop residue. Plant Ecol 213:18931905
[USDA-ERS] U.S. Department of Agriculture–Economic Research Service (2013) Organic production: Table 7. Certified organic beans. Acres of soybeans, dry beans, dry peas/lentils by State, 1997 and 2000–2011. USDA-ERS. Accessed October 26, 2015
[USDA-NASS] U.S. Department of Agriculture–National Agricultural Statistics Service (2014) 2012 United States Summary and State Data. Volume 1. Geographic Area Series. Part 51.,_Chapter_1_US/usv1.txt. Accessed May 5, 2014
[USDA-NRCS] U.S. Department of Agriculture–Natural Resources Conservation Service (2011) Carbon to nitrogen ratios in cropping systems. Available for download at: Accessed June 4, 2014
Wang, G, Ngouajio, M, Warncke, DD (2008) Nutrient cycling, weed suppression and onion yield following brassica and sorghum sudangrass cover crops. Hort Technol 18:6874
Weil, R, Kremen, A (2007) Perspective: thinking across and beyond disciplines to make cover crops pay. J Sci Food Agric 87:551557
Williams, JT, Harper, JL (1965) Seed polymorphism and germination I. The influence of nitrates and low temperatures on the germination of Chenopodium album . Weed Res 5:141150
Wilson, SD, Tilman, D (1995) Competitive responses of eight old-field plant species in four environments. Ecology 76:11691180


Type Description Title
Supplementary materials

Hill et al. supplementary material
Table S1-S3

 Word (24 KB)
24 KB


Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed