How Do Herbicides Affect Plants?
- Before herbicides were invented, farmers relied on natural techniques to control weeds. Farmers would use tillage to control the soil pH levels to ward off weeds. The first herbicides, commonly known as 2,4-D, were used in the late 1940s. The herbicide was easy and inexpensive to make and did an effective job of killing weeds but not crops. In the 1950s another form of herbicide, atrazine, was invented that has caused a great deal of environmental concerns because of its inability to naturally break down in the soil. The herbicide is known to have cause great groundwater contamination. Today, herbicides naturally decompose better than they did in the 1950s, so they do not have the same type of environmental impacts, but nonetheless, they still have environmental impacts.
- Herbicides are categorized as selective or non-selective and contact or systemic. Selective herbicides will kill weeds but not the crops around them. Non-selective herbicides kill all the weeds and plants where the herbicides are sprayed. Contact herbicides are fast-acting herbicides that attack the plant tissue. Systemic herbicides are absorbed into the plant through the roots and them the herbicide transfers throughout the plant, causing the plant to die.
- Herbicides may help farmers increase crop production. They can help increase the productivity of crops because they reduce the need for manual labor. More weeds may mean fewer crops for farmers. More weeds may cause a decrease in plants and eventually an increase in price for that specific plant. Weeds also carry diseases and pests that can kill plants. Clubroot is a disease that kills cabbage and radish that is commonly carried by weeds. Weeds also compete for soil, sunlight, nutrients and water from productive crops.
- With the development and use of herbicides also comes some considerations of their effect on plants. Weeds have evolved and become more resistant to herbicides as they are used more often. If a farmer wants to eliminate weeds, he has to use stronger herbicides that can be more harmful to other plants and the environment. The understanding of the use of herbicides and their impacts is relatively new and the effects on plants and the environment is just starting to be understood. It takes time to see the effects herbicides have on the environment because the changes happen over a long period of time.
- More health concerns have come out as more research is done on the chemicals used in herbicides. Herbicides have changed throughout the years and researchers still do not know the all the effects of the newer herbicides. Herbicides use chemicals that are very toxic and lethal to humans. If they are used improperly, they can cause serious harm to humans. Herbicides can also cross-contaminate soil and water and can kill healthy plants. Herbicides can be harmful to wildlife and the environment.
