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West Indian Dropseed/Giant Smutgrass (Sporobolus indicus var. pyramidalis) Control in Bahiagrass (Paspalum notatum) Pastures

Published online by Cambridge University Press:  20 January 2017

Paul Mislevy*
Affiliation:
Range Cattle Research and Education Center, University of Florida, IFAS, 3401 Experiment Station, Ona, FL 33865-9706
Frank G. Martin
Affiliation:
Statistics Department, University of Florida, IFAS, Gainesville, FL 32611-0339
David W. Hall
Affiliation:
Environmental Consultant, Forensic Botanist, 3666 NW 13th Place, Gainesville, FL 32605
*
Corresponding author's E-mail: [email protected]

Abstract

Field experiments were conducted in 1997 and 1998 to evaluate the effect of mowing followed by hexazinone for West Indian dropseed/giant smutgrass (Sporobolus indicus var. pyramidalis) (hereafter referred to as dropseed) control. The experimental design was a split plot, with mowing (nonmowed [mature] and 35-cm regrowth) as the whole plot and hexazinone rate (0.0 [control], 0.56, 0.84, 1.12, 1.40, and 1.68 kg ai/ha) as the subplot treatments. The application of 0.84 kg/ha hexazinone provided 94 and 81% dropseed control, 365 d after treatment (DAT) during 1997 and 1998, respectively. Increasing application rate to 1.12 kg/ha hexazinone provided 87 and 88% dropseed control, 365 DAT during 1997 and 1998, respectively. Both the 0.84 and 1.12 kg/ha rates provided the same average control (87.5%); however, the 1.12 kg/ha rate provided consistent control over years. Mowing dropseed, followed by hexazinone application at 35-cm regrowth, provided no additional control when compared with no mowing treatments. Rates of hexazinone at 1.40 and 1.68 kg/ha caused phytotoxicity to bahiagrass and increased bare soil surface area, especially 90 and 120 DAT. Phytotoxic effect on bahiagrass and on bare soil decreased 365 DAT, resulting in 75 to 80% total forage cover. Concentration and yield of total nonstructural carbohydrates were significantly lower for the mowed 35-cm regrowth treatment than for the nonmowed plants; however, even in its weakened condition this reduction had no effect on dropseed control.

Type
Research
Copyright
Copyright © Weed Science Society of America 

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References

Literature Cited

Hall, D. W. 1978. The Grasses of Florida. Ph.D. dissertation. University of Florida, Gainesville, FL. pp. 136142.Google Scholar
Hitchcock, A. S. 1950. Manual of the Grasses of the United States. 2nd ed. Washington, DC: U.S. Department of Agriculture Miscellaneous Publication 200. pp. 413, 418–419, 963.Google Scholar
Long, R. W. and Lakela, O. 1971. A Flora of Tropical Florida. Coral Gables, FL: University of Miami Press. pp. 139141.Google Scholar
McCaleb, J. E., Hodges, E. M., and Kirk, W. G. 1966. Smutgrass Control. Gainesville, FL: Florida Agricultural Experiment Station Circ. S149.Google Scholar
Mislevy, P., Shilling, D. G., Martin, F. G., and Hatch, S. L. 1999. Smutgrass (Sporobolus indicus) control in bahiagrass (Paspalum notatum) pastures. Weed Technol. 13: 571575.CrossRefGoogle Scholar
Mullahey, J. J. 2000. Evaluating grazing management systems to control giant smutgrass (Sporobolus indicus var pyramidalis). Proc. South. Weed Sci. Soc. 53: 59.Google Scholar
Nelson, N. 1944. A photometric adaptation of the Somogyi method for the determination of glucose. J. Biol. Chem. 153: 375380.Google Scholar
[SAS] Statistical Analysis Systems. 1985. SAS/STAT Users Guide. Version. 6, 5th ed, Volume 2. Cary, NC: Statistical Analysis Systems Institute. 956 p.Google Scholar
Small, J. K. 1933. Manual of the Southeastern Flora. Chapel Hill, NC: The University of North Carolina Press. pp. 100103.Google Scholar
Smith, D. 1981. Removing and Analyzing Total Nonstructural Carbohydrates from Plant Tissue. Wisconsin Agricultural Experiment Station Bulletin Rep. 2107. 14 p.Google Scholar
Somogyi, M. 1945. A new reagent for the determination of sugars. J. Biol. Chem. 160: 6168.CrossRefGoogle Scholar
Wunderlin, R. P. 1982. Guide to the Vascular Plants of Central Florida. Tampa, FL: University Press of Florida. pp. 9394.Google Scholar
Wunderlin, R. P. 1998. Guide to the vascular plants of Florida. Tampa, FL: University Press of Florida. pp. 135136.Google Scholar