Why care about weeds?
Maybe you are hoping to just peacefully coexist with your weeds, but according to Kira Sims, a Ph. D. candidate and graduate teaching and research assistant in the North Carolina State University Horticultural Science program, weeds:
- Compete for resources—such, as nutrients, space and sunlight—with more desirable plants.
- Can reduce crop yields.
- Adversely affect human health—some weeds such as ragweed and poison ivy can cause allergic reactions.
- Alter ecosystems—weeds can crowd out native plants or even make soil less hospitable to natives through altering pH, for example.
What can you do about weeds? IWM!
Integrated Weed Management is “Science-based, socially acceptable, environmentally responsible and economically practical crop protection against pests” says Sims, using all of the tools in your toolbox!
What’s in the toolbox?
Sims advocates the PAMS approach:
- Prevention tools include:
- Using clean (weed-free) compost, mulch, seeds, topsoil, transplants.
- Don’t let weeds reproduce—by setting seed, suckering and so on.
- Water desirable plants not weeds.
- Clean equipment that might transport weeds
- Remember you and your pets can transport weed seeds!
- Avoidance tools include:
- Clearly define where you want to exclude weeds
- Help your desirable plants outcompete the weeds by:
- Choosing appropriate plants
- Plant at the correct time
- Fertilize appropriately
- Rotate crops
- Monitoring tools:
- Scout for weeds regularly
- Keep records of crops and the weeds that cause problems
- Test soil to determine appropriate fertilization
- Suppression tools for when you can’t prevent or avoid all weeds:
- Reduce tilling—which brings up weed seeds
- Use narrow row spacing to shade out weeds
- Use cover crops and/or mulch over bare soil
- Manage irrigation
Article by Buncombe County Extension Master GardenerSM Volunteers
For more information:
Weed publications from NCSU, including specific links on managing crabgrass, Japanese stiltgrass, and ragweed: