Hostname: page-component-78c5997874-dh8gc Total loading time: 0 Render date: 2024-11-19T12:05:34.253Z Has data issue: false hasContentIssue false
  • English
  • Français

Weed Flora and Soil Properties in Subhumid Tropical Uganda

Published online by Cambridge University Press:  20 January 2017

Michael A. Ugen  and
Charles S. Wortmann
Michael A. Ugen
Affiliation:
Namulonge Agricultural and Animal Production Research Institute, P.O. Box 7084, Kampala, Uganda
Charles S. Wortmann*
Affiliation:
Centro Internacional de Tropical Agricultura
*
Corresponding author's E-mail: cwortmann2@unl.edu.
Get access Rights & Permissions [Opens in a new window]

Abstract

Small-scale African farmers typically have few resources for the management of weeds and soil fertility. Weed composition varies with soil properties and crops compete with weeds for available nutrients. We conducted field surveys in four districts to study the effects of cropping systems, fallow, landscape position, and soil characteristics on weed composition and evaluated the value of weed species density in predicting soil fertility conditions. Weed density was higher with annual than for banana-based cropping systems with higher relative densities of hairy beggarticks and garden spurge and lower relative densities for Cyperus spp. and johnsongrass in the banana-based systems. The relative densities of weed species varied with the length of the postfallow period, landscape position, drainage, and soil properties. Long-term rotation of annual and perennial cropping systems may be more effective than fallow in reducing total weed numbers, but fallow may be effectively used to reduce the relative densities of tropical spiderwort, Cyperus spp., and goosegrass. Relative densities of blue couch, goosegrass, garden spurge, Cyperus spp., oxalis, and johnsongrass varied more with nutrient supply than for other species. Soil properties had less effect on the distributions of tropic ageratum, hairy beggarticks, tropical spiderwort, and smallflower galinsoga. High relative densities of blue couch and garden spurge were generally associated with low soil nutrient levels. Goosegrass, johnsongrass, and oxalis were associated with higher nutrient levels. Information on the relationship of soil nutrient levels with weed flora was used to develop a decision guide to aid farmers in the identification of areas in their fields with severe nutrient deficiencies.

Keywords

Banana, Musa sppblue couch, Digitaria scalarum (Schweinf) Chiov # DIGSCgarden spurge, Euphorbia hirta L. # EPPHIgoosegrass, Eleusine indica (L.) Gaertn # ELEINhairy beggarticks, Bidens pilosa L. # BIDPIjohnsongrass, Sorghum halepense (L.) Pers. # SORHAoxalis, Oxalis latifolia; smallflower galinsoga, Galinsoga parviflora Cav. # GASPAtropic ageratum, Ageratum conyzoides # AGECOtropical spiderwort, Commelina benghalensis L. # COMBEBananadecision guidesindicator plantsrelative densitysoil fertility managementweed flora compositionweed managementRDrelative density
Type
Research
Information
Weed Technology , Volume 15 , Issue 3 , September 2001 , pp. 535 - 543
Copyright
Copyright © Weed Science Society of America 

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.)

Footnotes

Current address: Department of Agronomy and Horticulture, University of Nebraska, Lincoln NE 68583-0915

References

Literature Cited

Altieri, M. A. and Liebman, M. 1988. Weed management: Ecological guidelines. In Altieri, M. A. and Liebman, M., eds. Weed Management in Agroecosystems: Ecological Approaches. Boca Raton, FL: CRC Press. pp. 331–337.Google Scholar
Andersson, T. N. and Milberg, P. 1998. Weed flora and the relative importance of site, crop, crop rotation and nitrogen. Weed Sci. 46: 30–38.Google Scholar
Andreasen, C. and Streibig, J. C. 1991. Soil properties affecting the distribution of 37 weed species in Danish fields. Weed Res. 31: 181–187.Google Scholar
Banks, P. A., Santelmann, P. W., and Tucker, B. B. 1976. Influence of long term soil fertility treatments on weed species in winter wheat. Agron. J. 68: 825–827.Google Scholar
Carlson, H. L. and Hill, J. E. 1985. Wild oat (Avena fatua) competition with spring wheat: effects of nitrogen fertilization. Weed Sci. 34: 29–33.Google Scholar
Cromar, H. E., Murphy, S. D., and Swanton, C. J. 1999. Influence of tillage and crop residue on postdispersal predation of weed seeds. Weed Sci. 47: 184–194.Google Scholar
Derksen, D. A., Thomas, A. G., Lafond, G. P., Loeppky, H. A., and Swanton, C. J. 1994. Impact of agronomic practices on weed communities: fallow within tillage systems. Weed Sci. 42: 184–194.Google Scholar
Froud-Williams, R. J. 1988. Changes in weed flora with different tillage and agronomic management systems. In Altieri, M. A. and Liebman, M., eds. Weed Management in Agroecosystems: Ecological Approaches. Boca Raton, FL: CRC Press. pp. 213–236.Google Scholar
Harrop, J. F. 1970. Soil. In Jameson, J. D., ed. Agriculture in Uganda. Oxford University Press, UK. pp. 43–71.Google Scholar
Heady, H. F., Gibbons, R. P., and Powell, R. W. 1959. A comparison of the charting, line intercept and line point methods of sampling shrub types of vegetation. J. Range Manage. 12: 180–188.Google Scholar
Kegode, G. O., Forcella, F., and Clay, S. 1999. Influence of crop rotation, tillage and management inputs on weed seed production. Weed Sci. 47: 175–183.Google Scholar
Kennedy, A. C. and Kremer, R. J. 1996. Microorganisms in weed control strategies. J. Prod. Agric. 9: 480–485.Google Scholar
Mohler, C. L. 1996. Ecological basis for the cultural control of annual weeds. J. Prod. Agric. 9: 468–474.Google Scholar
Olsen, S. R., Cole, C. V., Watanabe, F. S., and Dean, L. A. 1954. Estimation of available phosphorus in soils by extraction with sodium bicarbonate. U.S. Dept. of Agric. Circ. 939.Google Scholar
Peterson, D. E. and Nalewaja, J. D. 1992. Environment influences green foxtail (Setaria viridis) competition with wheat (Triticum aestivum). Weed Technol. 6: 607–610.Google Scholar
Statistix for Windows. 1998. Analytical Software, Tallahassee, FL.Google Scholar
Swanton, C. J., Clements, D. R., and Derksen, D. A. 1993. Weed succession under conservation tillage: a hierarchical framework for research and management. Weed Technol. 7: 286–297.CrossRefGoogle Scholar
Swanton, C. J., Shrestha, A., Robert, C. R., and Knezevic, S. Z. 1999. Effect of tillage systems, N and cover crop on the composition of weed flora. Weed Sci. 47: 454–461.Google Scholar
Wortmann, C. S. and Kaizzi, C. K. 1998. Nutrient balances and expected effects of alternative practices in farming systems of Uganda. Agric. Ecosys. Environ. 71: 115–130.Google Scholar