UC IPM Online UC ANR home page UC IPM home page


SKIP navigation


Research and IPM

Grants Programs: Projects Database

Project description

Using a Longer Harvest Interval to Control Nutsedge in Alfalfa. (97CC025)
Program UC IPM competitive research grants program
R. Kallenbach, Cooperative Extension, Riverside County
Host/habitat Alfalfa
Pest Nutsedge
Discipline Weed Science
Cultural Controls
Start year (duration)  1997 (One Year)
Objectives Determine if longer harvest intervals during summer can control nutsedge growth and reproduction in alfalfa.

Document how this cultural control method compares to chemical control of nutsedge in alfalfa.

Determine if cultural control is an economically viable method to suppress nutsedge growth in alfalfa fields.

Hay yields (alfalfa and nutsedge combined) were the same for plots that received Eptam or were left untreated for similar harvest intervals. When combined across chemical treatments, hay yields from April through September were 4.34, 4.95, and 4.81 tons per acre for hay harvested every 28, 35, or 42 days respectively.

Forage samples from plots harvested every 28 days and that received Eptam contained 32% nutsedge compared to 43% for untreated plots. In plots harvested every 35 or 42 days hay average 35% nutsedge and the botanical composition was unaffected by either the use of Eptam or cutting interval. These data suggest that Eptam is only beneficial when harvesting alfalfa on a short cutting interval.

Nutsedge density averaged 82 plants per m2 at the beginning of the study. Fourteen days after each harvest we counted these populations again. In plots harvested every 28 days, nutsedge declined by 81% to 15 plants per m2 when Eptam was applied. In plots harvested every 35 or 42 days, an Eptam application reduced the nutsedge population to 11 and 12 plants per m2 respectively. In untreated plots, regardless of the number of days between harvests, the nutsedge population remained the same as at the beginning of the study. These data demonstrate the effectiveness of Eptam as means of controlling nutsedge in alfalfa.

Top of page

Statewide IPM Program, Agriculture and Natural Resources, University of California
All contents copyright 2020 The Regents of the University of California. All rights reserved.

For noncommercial purposes only, any Web site may link directly to this page. FOR ALL OTHER USES or more information, read Legal Notices. Unfortunately, we cannot provide individual solutions to specific pest problems. See our Home page, or in the U.S., contact your local Cooperative Extension office for assistance.

Agriculture and Natural Resources, University of California

Accessibility   web template revised: July 8, 2020 Contact webmaster.