AUBURN, Alabama—Everyone has an interest in controlling weeds. Whether a homeowner or a farmer, weeds affect everyone.
Dr. Joyce Tredaway, and Alabama Cooperative Extension System weed scientist, said her occupation draws questions from people in all walks of life.
Weeds Impact Everything
Tredaway said it is important to understand the impact weeds have on everyday life—from food and fiber production to water resources, recreation, schools and public areas.
“Many people that I encounter think of their lawns when they have general questions about weeds,” she said. “But weeds and their impacts reach much further than landscaping and making yards more beautiful. Weed management is important, not only aesthetically and for better yields, but also economically to growers and the general public.”
Weeds Impact Growers and Crops
Weeds compete with cultivated crop plants for light, water and nutrients.
“Generally weeds are better competitors because they are better adapted to the environment,” Tredaway said.
She said weeds are especially competitive if they are indigenous to the area, therefore causing reduced crop productivity.
Weeds can harbor insects, disease and pathogens—allowing them to invade crop plants. The result is an increase in cost of disease and insect controls, which directly increases production costs. In order to increase yields by reducing competition, weeds must be controlled by hand weeding, herbicides, cover crops, tillage and other methods. These methods will increase the cost of crop production.
“Some weeds interfere with harvesting and the seed being harvested becomes contaminated with weed seed,” Tredaway said. “Certain weed seed is very small and cannot be separated by the thresher during harvest.”
When this occurs, seed quality is reduced and producers get a lower market value for crop seed. Weeds can also cause lower prices related to the sale of livestock. For example, milk prices may drop because of wild onion, wild garlic or bitterweed flavor in milk. Common cocklebur can also reduce the quality of wool.
Other weed seed is poisonous or injurious to livestock and humans. Numerous livestock health issues—including death—can be attributed to poisonous plants. Similarly, during the fall, common ragweed is in full bloom and humans spend millions of dollars on the whole trying to control symptoms and loss of work. Plants like poison ivy also cause extreme discomfort and may warrant a doctor visit.
Weeds in Public Places
Weeds reduce the aesthetic value of public parks, golf courses and school grounds, in addition to lawns and neighborhood common areas.
Water management issues may also result from a lack of weed control. While fishermen may prefer aquatic weeds, the plants can cause issues for propeller fishing boats. Weeds can also become major problems for irrigation and drainage systems, lakes, harbors and reservoirs. Unwanted plants may restrict water flow and taint water with undesirable flavors.
“Weeds around ponds, swimming pools, canals and other water bodies cause an abundance of mosquitoes,” Tredaway said. “Mosquitoes not only affect humans, but may affect animals as well. Mosquito control is difficult and expensive, especially in large areas.”
Weeds vs. Efficiency
Efficient control of weeds is time consuming and expensive. The cost of control directly affects the price of food production, thus affecting the price of food and other agricultural products.
Tredaway said without these control methods, food and other products would be difficult to obtain—driving prices higher.
Weeds result in less efficient land use because the land cannot reach full productivity capacity.
“Lower human efficiency is also associated with weed management,” she said. “Much of the world uses human hand-weeding and pulling to control weeds. In the U.S. most of the human labor is in the fruit and vegetable production systems. However, in Africa, India, China and other countries, human labor is the means by which to weed crops.”
She adds that weeds also affect human safety. Stop signs blocked by protruding weeds are safety hazards.
“As you can see, weeds can affect virtually every aspect of life,” Tredaway said.
Photo by J. Bicking/shutterstock.com.