Once an established weed problem is identified, an appropriate control method needs to be determined. Cultural practices such as application of lime and fertilizer will increase the ability of desired pasture plants to compete. Generally speaking, a thick and healthy crop of grass will crowd out undesirable plants, prevent establishment of new weed seeds and utilize a majority of the water, sun and nutrients available for growth. Many weed species are indicators of poor soil fertility and are good sign that soil pH and soil nutrient testing is warranted.
Mechanical control such as mowing or clipping pastures is also an effective method of controlling weed populations. Mowing improves the pasture’s appearance, temporarily increases forage production and properly timed will prevent weeds from producing seeds. Mowing is more effective on annual weeds than perennial weeds and broadleaf weeds more than grass weeds.
Biological control involves using other living things to control weeds such as plants, herbivores, insects and nematodes. These methods are unlikely to provide complete control, but will often suppress the weed population to a manageable level.
Chemical weed control involves the use of herbicides. Herbicides should be selected based on forage species being grown, weed species to be controlled, cost and ease of application. Environmental impact should also be considered. Choosing the proper herbicide and application rate is extremely important. Herbicides must be applied at the correct rate and time to be cost effective.
Maintaining a healthy, productive pasture will reduce the population of weedy plants. Good pasture management such as pH testing, fertilization and controlled grazing will result in healthy pastures. Adding new grass and legumes by frost seeding or using a no-till drill will improve forage quality. While we can’t hope to eradicate all weeds, an integrated weed-management strategy involving scouting, prevention and control is the most economical and environmentally friendly approach to pasture weed management.
For questions regarding pasture management, grazing livestock or small-farm questions, contact Peter Hagar at Cornell Cooperative Extension’s Clinton County office at 561-7450 or email me at email@example.com.
Peter Hagar, agriculture educator, Cornell Cooperative Extension Clinton County, 6064 Route 22, Suite 5, Plattsburgh, 12901. Phone 561-7450 or email Phh7@cornell.edu.