Integrated Management of Purple and Yellow Nutsedge in Organic Vegetable Production

Project Overview

LS05-170
Project Type: Research and Education
Funds awarded in 2005: $125,000.00
Projected End Date: 12/31/2007
Region: Southern
State: Florida
Principal Investigator:
Dr. Carlene Chase
University of Florida

Annual Reports

Commodities

  • Vegetables: broccoli, greens (lettuces), peppers, turnips

Practices

  • Crop Production: cover crops, fallow, strip tillage
  • Education and Training: extension, on-farm/ranch research, participatory research
  • Farm Business Management: budgets/cost and returns
  • Pest Management: competition, cultural control, flame, physical control, mulching - plastic, soil solarization, mulching - vegetative
  • Production Systems: holistic management
  • Soil Management: green manures

    Abstract:

    In Gainesville summer fallow tillage and infrared transmitting (IRT) film used in combination with a vigorous crop can effectively suppress purple nutsedge infested areas for organic production. In Tifton, yellow nutsedge and other weeds were suppressed by IRT film but propane flaming, sunn hemp cover crop, and fallow-tillage the preceding summer were not effective. Yellow nutsedge was absent from fall-seeded crops in both years, regardless of the preceding summer treatment, suggesting that the timing of cultural practices may be a useful means to avoid losses from yellow nutsedge. At Clemson, frequent tillage or use of IRT film with or without turnip followed by handweeding was not effective in eradicating purple nutsedge. Season-long management was essential to prevent increases in purple nutsedge tuber density over time.

    Project objectives:

    The overall objective of this project is to evaluate weed management strategies for use in the integrated management of purple nutsedge and yellow nutsedge in organic vegetable production systems for the southeastern US.

    Gainesville, Florida

    1. To compare of the summer fallow techniques of a summer cover crop, soil solarization, clean fallow with disking, clean fallow with flaming, and a weedy fallow on purple nutsedge population density, tuber number and size distribution, and tuber viability.

    2. To evaluate the persistence of suppression in two subsequent fall cash crops with differing canopy sizes and rates of growth and development.

    3. To compare the effect of clean fallow and an allelopathic winter cover crop on purple nutsedge tuber viability.

    4. To assess the effect of spring crops of differing canopy type and rate of growth and development and weed-suppressive synthetic mulch (IRT – infrared transmitting film).

    5. To identify a combination of treatments applied in sequence that result in the most cost effective and efficacious suppression of purple nutsedge.

    Tifton, Georgia

    1. To compare of the summer fallow techniques of a summer cover crop, soil solarization, clean fallow with disking, clean fallow with flaming, and a weedy fallow on yellow nutsedge population density, tuber number and size distribution, and tuber viability.

    2. To evaluate the persistence of suppression in two subsequent fall cash crops with differing canopy sizes and rates of growth and development.

    3. To compare the effect of clean fallow and an allelopathic winter cover crop on yellow nutsedge tuber viability.

    4. To assess the effect of spring crops of differing canopy type and rate of growth and development and weed-suppressive synthetic mulch (IRT – infrared transmitting film).

    5. To identify a combination of treatments applied in sequence that result in the most cost effective and efficacious suppression of yellow nutsedge.

    Clemson, South Carolina

    Objectives

    1. To evaluate purple nutsedge tuber dynamics over two growing seasons using various integrated strategies in organically grown fall-planted bell pepper.

    2. To compare the economics of various integrated strategies for purple nutsedge management.

    Gainesville Economic Analysis

    To compare the monetary costs and returns to producers in comparisons to conventional (non-organic) production systems, non-market environmental and social benefits associated with reduced consumption of pesticides, and regional economic impacts of expanded local vegetable production.

    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.