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

    Proposal abstract:

    A multistate on-farm and research farm evaluation of serial integrated crop management systems will be conducted to manage purple and yellow nutsedge in organic vegetables in the southeastern US. A multi-pronged approach that involves yearlong management during fallow and cropping periods will be employed. The integration of several of strategies into a systems approach to vegetable crop management may provide improved nutsedge suppression and crop yields. Control methods will include soil solarization, cover crops, clean fallows with tillage or flaming, suppressive mulch, and biofumigation. Knowledge of the weeds’ biology is central to this approach. Thus, methods either focus on reducing the existing reservoir of tubers in the soil, by directly killing the tubers or indirectly through depletion of reserves; or aim to decrease subsequent tuber production with competitive crops and suppressive mulch. Economic analysis is being undertaken as part of the holistic approach to ensure that systems that are practical for organic growers and effective in suppressing yellow and purple nutsedge are also economically feasible.

    Project objectives from proposal:

    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 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 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

    To integrate tillage, solarization, an IRT film, a biofumigation/cover crop, mulching, and mowing as multi-facet strategies for suppressing purple nutsedge in organically grown bell pepper.

    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.