Hostname: page-component-cd9895bd7-7cvxr Total loading time: 0 Render date: 2024-12-26T17:36:26.101Z Has data issue: false hasContentIssue false
  • English
  • Français

Increased weed diversity, density and above-ground biomass in long-term organic crop rotations

Published online by Cambridge University Press:  18 June 2010

Sam E. Wortman ,
John L. Lindquist ,
Milton J. Haar  and
Charles A. Francis
Sam E. Wortman*
Affiliation:
Department of Agronomy and Horticulture, University of Nebraska-Lincoln, Plant Science Hall 279, Lincoln, NE68583, USA.
John L. Lindquist
Affiliation:
Department of Agronomy and Horticulture, University of Nebraska-Lincoln, Plant Science Hall 279, Lincoln, NE68583, USA.
Milton J. Haar
Affiliation:
Southwest Research and Outreach Center, University of Minnesota, 23669 130th Street, Lamberton, MN56152, USA.
Charles A. Francis
Affiliation:
Department of Agronomy and Horticulture, University of Nebraska-Lincoln, Plant Science Hall 279, Lincoln, NE68583, USA.
*
*Corresponding author: sam.wortman@huskers.unl.edu
Get access Rights & Permissions [Opens in a new window]

Abstract

While weed management is consistently a top priority among farmers, there is also growing concern for the conservation of biodiversity. Maintaining diverse weed communities below bioeconomic thresholds may provide ecosystem services for the crop and the surrounding ecosystem. This study was conducted to determine if weed diversity, density and biomass differ within and among organic and conventional crop rotations. In 2007 and 2008, we sampled weed communities in four long-term crop rotations near Mead, Nebraska using seedbank analyses (elutriation and greenhouse emergence) and above-ground biomass sampling. Two conventional crop rotations consisted of a corn (Zea mays) or sorghum (Sorghum bicolor)–soybean (Glycine max)–sorghum or corn–soybean sequence and a diversified corn or sorghum–sorghum or corn–soybean–wheat (Triticum aestivum) sequence. Two organic rotations consisted of an animal manure-based soybean–corn or sorghum–soybean–wheat sequence and a green manure-based alfalfa (Medicago sativa)–alfalfa–corn or sorghum–wheat sequence. Species diversity of the weed seedbank and the above-ground weed community, as determined by the Shannon diversity index, were greatest in the organic green manure rotation. Averaged across all sampling methods and years, the weed diversity index of the organic green manure rotation was 1.07, followed by the organic animal manure (0.78), diversified conventional (0.76) and conventional (0.66) rotations. The broadleaf weed seedbank density in the tillage layer of the organic animal manure rotation was 1.4×, 3.1× and 5.1× greater than the organic green manure, diversified conventional and conventional rotations, respectively. The grass weed seedbank density in the tillage layer of the organic green manure rotation was 2.0×, 6.1× and 6.4× greater than the organic animal manure, diversified conventional and conventional rotations, respectively. The above-ground weed biomass was generally greatest in the organic rotations. The broadleaf weed biomass in sorghum and wheat did not differ between organic and conventional rotations (CRs), but grass weed biomass was greater in organic compared to CRs for all crops. The above-ground weed biomass did not differ within CRs, and within organic rotations the grass weed biomass was generally greatest in the organic green manure rotation. The weed seedbank and above-ground weed communities that have accumulated in these rotations throughout the experiment suggest a need for greater management in long-term organic rotations that primarily include annual crops. However, results suggest that including a perennial forage crop in organic rotations may reduce broadleaf weed seedbank populations and increase weed diversity.

Keywords

weed seedbankbiodiversitylong-term crop rotationsorganic farminganimal manureperennial forage
Type
Research Papers
Information
Renewable Agriculture and Food Systems , Volume 25 , Issue 4 , December 2010 , pp. 281 - 295
Copyright
Copyright © Cambridge University Press 2010

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1El Titi, A. 1995. Ecological aspects of integrated farming. In Glen, D.M., Greaves, M.P., and Anderson, H.M. (eds). Ecology and Integrated Farming Systems. John Wiley and Sons, New York. p. 243–256.Google Scholar
2Altieri, M.A. 1994. Biodiversity and Pest Management in Agroecosystems. Food Product Press, New York.Google Scholar
3Zimdahl, R.L. 2004. Weed-Crop Competition: A Review. Blackwell Publishing, Ames.CrossRefGoogle Scholar
4Leeson, J.Y., Sheard, J.W., and Thomas, A.G. 2000. Weed communities associated with arable Saskatchewan farm management systems. Canadian Journal of Plant Science 80:177–185.CrossRefGoogle Scholar
5Murphy, S.D., Clements, D.R., Belaoussoff, S., Kevan, P.G., and Swanton, C.J. 2006. Promotion of weed species diversity and reduction of weed seedbanks with conservation tillage and crop rotation. Weed Science 54:69–77.CrossRefGoogle Scholar
6Mahn, E.G. 1984. Structural changes of weed communities and populations. Vegetatio 58:79–85.CrossRefGoogle Scholar
7Wicks, G.A., Smika, D.E., and Hergert, G.W. 1988. Long-term effects of no-tillage in a winter wheat (Triticum aestivum)–sorghum (Sorghum bicolor)–fallow rotation. Weed Science 21:23–28.Google Scholar
8Moreby, S.J. and Southway, S.E. 1999. Influence of autumn applied herbicides on summer and autumn food availability to birds in winter wheat fields in southern England. Agriculture, Ecosystems and Environment 72:285–297.CrossRefGoogle Scholar
9Menalled, F.D., Gross, K.L., and Hammond, M. 2001. Weed aboveground and seedbank community responses to agricultural management systems. Ecological Applications 11:1586–1601.CrossRefGoogle Scholar
10Palmer, M.W. and Maurer, T.A. 1997. Does diversity beget diversity? A case study of crops and weeds. Journal of Vegetation Science 8:235–240.CrossRefGoogle Scholar
11USDA NOP. 2008. United States Department of Agriculture National Organic Program. Available at Web site http://www.ams.usda.gov/ (accessed November 24, 2008).Google Scholar
12Hooper, D.U., Chapin, F.S. III, and Ewel, J.J. 2005. Effects of biodiversity on ecosystem functioning: a consensus of current knowledge. Ecological Monographs 75:3–35.CrossRefGoogle Scholar
13Hald, A.B. 1999. Weed vegetation (wild flora) of long established organic versus conventional cereal fields in Denmark. Annals of Applied Biology 134:307–314.CrossRefGoogle Scholar
14Gruber, H., Handel, K., and Broschewitz, B. 2000. Influence of farming system on weeds in thresh crops of a six-year crop rotation. Journal of Plant Diseases and Protection 17:33–40.Google Scholar
15Rydgerg, N.T. and Milberg, P. 2000. A survey of weeds in organic farming in Sweden. Biological Agriculture and Horticulture 18:175–185.CrossRefGoogle Scholar
16Moonen, A.C. and Barberi, P. 2004. Size and composition of the weed seedbank after 7 years of different cover-crop-maize management systems. Weed Research 44:163–177.CrossRefGoogle Scholar
17Davis, A.S., Renner, K.A., and Gross, K.L. 2005. Weed seedbank and community shifts in a long-term cropping systems experiment. Weed Science 53:296–306.CrossRefGoogle Scholar
18Cavers, P.B. 1995. Seed banks: memory in soil. Canadian Journal of Soil Science 75:11–13.CrossRefGoogle Scholar
19Thompson, K., Bakker, J., and Bekker, R. 1997. The Soil Seed Banks of North West Europe: Methodology, Density, and Longevity. Cambridge University Press, Cambridge.Google Scholar
20Buhler, D.D., Hartzler, R.G., and Forcella, F. 1997. Implications of weed seedbank dynamics to weed management. Weed Science 45:329–336.CrossRefGoogle Scholar
21Barberi, P. and Lo Cascio, B. 2001. Long-term tillage and crop rotation effects on weed seedbank size and composition. Weed Research 41:325–340.CrossRefGoogle Scholar
22Mayor, J.P. and Dessaint, F. 1998. Influence of weed management strategies on soil seedbank diversity. Weed Research 38:95–105.CrossRefGoogle Scholar
23Squire, G.R., Rodger, S., and Wright, G. 2000. Community-scale seedbank response to less intense rotation and reduced herbicide input at three sites. Annals of Applied Biology 136:47–57.CrossRefGoogle Scholar
24Hyvonen, T. and Salonen, J. 2003. Weed seedbank development under low-input and conventional cropping practices. Aspects of Applied Biology 69:119–124.Google Scholar
25Legere, A., Stevenson, F.C., and Benoit, D.L. 2005. Diversity and assembly of weed communities: contrasting responses across cropping systems. Weed Research 45:303–315.CrossRefGoogle Scholar
26Liebman, M. and Dyck, E. 1993. Crop rotation and intercropping strategies for weed management. Ecological Applications 3:92–122.CrossRefGoogle ScholarPubMed
27Barberi, P., Silvestri, N., and Bonari, E. 1997. Weed communities of winter wheat as influenced by input level and rotation. Weed Research 37:301–313.CrossRefGoogle Scholar
28Clay, S.A. and Aguilar, I. 1998. Weed seedbanks and corn growth following continuous corn or alfalfa. Agronomy Journal 90:813–818.CrossRefGoogle Scholar
29Cardina, J., Herms, C.P., and Doohan, D.J. 2002. Crop rotation and tillage system effects on weed seedbanks. Weed Science 50:448–460.CrossRefGoogle Scholar
30Teasdale, J.R., Mangum, R.W., Radhakrishnan, J., and Cavigelli, M.A. 2004. Weed seedbank dynamics in three organic farming crop rotations. Agronomy Journal 96:1429–1435.CrossRefGoogle Scholar
31Cavigelli, M.A., Teasdale, J.R., and Conklin, A.E. 2008. Long-term agronomic performance of organic and conventional field crops in the Mid-Atlantic region. Agronomy Journal 100:785–794.CrossRefGoogle Scholar
32Menalled, F.D., Liebman, M., and Buhler, D.D. 2004. Impact of composted swine manure and tillage on common waterhemp (Amaranthus rudis) competition with soybean. Weed Science 52:605–613.CrossRefGoogle Scholar
33Walz, E. 1999. Third Biennial Organic Farmers Survey. Organic Farming Research Foundation, Santa Cruz, CA.Google Scholar
34[MNDA] Minnesota Department of Agriculture. 2007. Overview: Experiences and outlook of Minnesota organic farmers. Available at Web site http://www.mda.state.mn.us/news/publications/food/organicgrowing/2007orgsurvresults.pdf (accessed August 24, 2009).Google Scholar
35Lesoing, G. 1992. Alternative cropping systems for eastern Nebraska. Doctoral dissertation, University of Nebraska-Lincoln.Google Scholar
36Drinkwater, L.E. 2002. Cropping systems research: reconsidering agricultural experimental approaches. HortTechnology 12:355–361.CrossRefGoogle Scholar
37Colbach, N., Dessaint, F., and Forcella, F. 2000. Evaluating field-scale sampling methods for the estimation of mean plant densities of weeds. Weed Research 40:411–430.CrossRefGoogle Scholar
38Wiles, L.J., Barlin, D.H., Schweizer, E.E., Duke, H.R., and Whitt, D.E. 1996. A new soil sampler and elutriator for collecting and extracting weed seeds from soil. Weed Technology 10:35–41.CrossRefGoogle Scholar
39Sosnoskie, L.M., Herms, C.P., and Cardina, J. 2006. Weed seedbank composition in a 35-yr-old tillage and rotation experiment. Weed Science 54:263–273.CrossRefGoogle Scholar
40Liebman, M. and Davis, A. 2000. Integration of soil, crop and weed management in low-external-input farming systems. Weed Research 40:27–47.CrossRefGoogle Scholar
41Mt. Pleasant, J. and Schlather, K.J. 1994. Incidence of weed seed in cow (Bos sp.) manure and its importance as a weed source for cropland. Weed Technology 8:304–310.CrossRefGoogle Scholar
42Hume, L. 1987. Long-term effects of 2,4-D application on plants. I. Effects on the weed community in a wheat crop. Canadian Journal of Botany 65:2530–2536.CrossRefGoogle Scholar
43Kegode, G.O., Forcella, F., and Clay, S. 1999. Influence of crop rotation, tillage, and management inputs on weed seed production. Weed Science 47:175–183.CrossRefGoogle Scholar
44Sjursen, H. 2001. Change of the weed seed bank during the first complete six-course crop rotation after conversion from conventional to organic farming. Biological Agriculture and Horticulture 19:71–90.CrossRefGoogle Scholar
45Porter, P.M., Huggins, D.R., Perillo, C.A., Quiring, S.R., and Crookston, R.K. 2003. Organic and other management strategies with two- and four-year crop rotations in Minnesota. Agronomy Journal 95:233–244.CrossRefGoogle Scholar
46Risser, P.G. 1969. Competitive relationships among herbaceous grassland plants. The Botanical Review 35:251–284.CrossRefGoogle Scholar
47Norris, R.F. and Ayres, D. 1991. Cutting interval and irrigation timing in alfalfa: yellow foxtail invasion and economic analysis. Agronomy Journal 83:552–558.CrossRefGoogle Scholar
48Teasdale, J.R. and Daughtry, C.S.T. 1993. Weed suppression by live and dessicated hairy vetch (Vicia villosa). Weed Science 41:207–212.CrossRefGoogle Scholar
49Roberts, H.A. and Feast, P.M. 1973. Changes in the numbers of viable weed seeds in soil under different regimes. Weed Research 13:298–303.CrossRefGoogle Scholar
50Seibert, A.C. and Pearce, R.B. 1993. Growth analysis of weed and crop species with reference to seed weight. Weed Science 41:52–56.CrossRefGoogle Scholar
51Tilman, D. 1987. Secondary succession and the pattern of plant dominance along experimental nitrogen gradients. Ecological Monographs 57:189–214.CrossRefGoogle Scholar
52Aerts, R., Berendse, F., de Caluwe, H., and Schmitz, M. 1990. Competition in heathland along an experimental gradient of nutrient availability. Oikos 57:310–318.CrossRefGoogle Scholar
53Wedin, D. and Tilman, D. 1993. Competition among grasses along a nitrogen gradient: initial conditions and mechanisms of competition. Ecological Monographs 63:199–229.CrossRefGoogle Scholar
54Wortman, S. 2009. Long-term organic and conventional crop rotations: yields, soil fertility and weed communities. M.S. thesis, University of Nebraska-Lincoln.Google Scholar
55Ball, D.A. 1992. Weed seedbank response to tillage, herbicides, and crop rotation sequence. Weed Science 40:654–659.CrossRefGoogle Scholar
56Posner, J.L., Baldock, J.O., and Hedtcke, J.L. 2008. Organic and conventional production systems in the Wisconsin integrated cropping systems trials. I. Productivity 1990–2002. Agronomy Journal 100:253–260.CrossRefGoogle Scholar
57Hoffman, M., Weston, L., Snyder, J., and Regnier, E. 1996. Allelopathic influence of germinating seeds and seedlings of cover crops on weed species. Weed Science 44:579–584.CrossRefGoogle Scholar
58Ma, Y. 2005. Allelopathic studies of common wheat. Weed Biology and Management 5:93–104.CrossRefGoogle Scholar
59Zasada, I.A., Linker, H.M., and Coble, H.D. 1997. Initial weed densities affect no-tillage weed management with a rye (Secale cereale) cover crop. Weed Technology 11:473–477.CrossRefGoogle Scholar
60Buhler, D.D. 1999. Weed population responses to weed control practices. I. Seedbank, weed populations and crop yields. Weed Science 47:416–422.CrossRefGoogle Scholar
61Bond, W. and Grundy, A.C. 2001. Non-chemical weed management in organic farming systems. Weed Research 41:383–405.CrossRefGoogle Scholar
62Liebman, M. and Davis, A.S. 2009. Managing weeds in organic farming systems: an ecological approach. In Francis, C. (ed.). Organic Farming: The Ecological System. Agronomy Monograph 54, ASA-CSSA-SSSA, Madison, WI. p. 173–195.Google Scholar
63Liebman, M. and Gallandt, E.R. 1997. Many little hammers: ecological approaches for management of crop-weed interactions. In Jackson, L.E. (ed.). Ecology in Agriculture. Academic Press, San Diego, CA.Google Scholar
64Marshall, E.J.P., Brown, V.K., Boatman, N.D., Lutman, P.J.W., Squire, G.R., and Ward, L.K. 2003. The role of weeds in supporting biological diversity within crop fields. Weed Research 43:77–89.CrossRefGoogle Scholar
65Swift, M.J. and Anderson, J.M. 1994. Biodiversity and Ecosystem Function in Agricultural Systems. In Schulze, E.D. and Mooney, H.A. (eds). Biodiversity and Ecosystem Function. Springer-Verlag, Berlin. p. 15–41.CrossRefGoogle Scholar
66Mader, P., Fliebbbach, A., Dubois, D., Gunst, L., Fried, P., and Niggli, R. 2002. Soil fertility and biodiversity in organic farming. Science 296:1694–1697.CrossRefGoogle ScholarPubMed
67Mineau, P. and McLaughlin, A. 1996. Conservation of biodiversity within Canadian agricultural landscapes: integrating habitat for wildlife. Journal of Agricultural and Environmental Ethics 9:93–113.CrossRefGoogle Scholar