Western Sustainable Agriculture Research & Education
(SARE) Farm Internship Curriculum and Handbook
- What is a weed?
- How are weeds dispersed?
- What are some benefits of weeds in a cropping system?
- What are some of the characteristics of weeds that allow them to compete so well in cropping systems?
- Why control weeds?
Definition - What is a weed?
A weed is any plant, native or non-native, that interferes with crop production by doing more harm than good and has a habit of encroaching where it is not wanted.
- Crop competition and its effect on crop yield and quality
- Nutrient competition
- Light competition
- Water competition
- Interference with harvesting operations
- Example: Weed roots such as bindweed wrap around sub-soil blades used for undercutting root crops during harvest
- Enhance soil structure
- Improve soil tilth
- Cycle nutrients
- Provide habitat for beneficial insects
- Improve soil water infiltration
Weed Prevention Strategies
- Improve soil tilth, aeration, water infiltration, and fertility to optimize crop growth and minimize weed pressure
- Thoroughly clean equipment before moving it from one farm or location to another
- Do not allow weeds to form seed heads and/or perennial rooting structures in the cropping system
- Thoroughly compost all imported animal manures to insure destruction of viable weed seed
- Filter surface irrigation water to avoid importing weed seeds
- Work with neighbors to eliminate or minimize the potential for spread of noxious and problematic weeds from adjacent lands
- Tour fields and identify most common weeds (star thistle, pigweed, purslane, chicory, wild lettuce, grasses, etc.)
- Pull or dig selected weeds and examine root system
Management through Manual Cultivation
- Demonstrate and practice proper techniques with various tools - wheel hoe, stirrup hoe, collinear hoe, and Mexican hoe. Discuss need for follow-up cultivation.
- Benefits - eliminates weeds, stirs soil and breaks crust (allows for easier penetration of air and water)
This page was last updated on: August 25, 2014