Weeds are crops that grow where they are not wanted. Their presence affects the growth and performance of target crops. They compete for resources and act as disease hosts. Weeds need to be controlled before and soon after, they start sprouting. Despite all the advancements in weed control, farmers still find it challenging to effectively control weeds. There are various methods to control weeds that will be discussed in detail in this article.
Precision hoeing involves using advanced farm machinery to prepare land or control weeds. A precision hoe is operated by a tractor that is guided by GPS when removing weeds in the farm. Some advanced precision hoes have high-resolution cameras that are used to differentiate weeds and target crops. This article provides you with in-depth information about weed control and precision hoeing.
Weeds can be controlled using various techniques. This includes cultural, biological, chemical and mechanical methods. Each method works differently on different weed species, hence the need for integrating several methods to control single weed species. There are numerous control methods, but we will focus on the most important and effective methods.
Cultural Weed Control Methods
This age-old method involves planting different crops each cycle in a single season. Rotating different crops deprives the weed the necessary conditions to thrive. This includes a host plant, and natural resources. It is commonly applied in horticulture where the solanacea family of tomatoes or potatoes is intercropped with the gramminae family of maize or wheat.
Intercropping is planting two or more crops together. The intercrops grow fast and have dense vegetation that covers the ground suppressing the growth of weeds. Intercropping tall crops like maize in an area with short weeds deprives them off sunlight that limits their growth. You can also intercrop cover crops such as beans, which cover the soil surface leaving no room for weeds to grow.
Choosing the Right Crop Variety
Weeds often dominate in areas where the target crops are weak. To ensure this does not occur, plant varieties, which are vigorous and grow faster than the weeds. By doing so, weeds are unable to compete with the target crop and hence grow slowly and do not multiply fast.
Use Clean Planting Materials
Weed seeds can be transmitted through planting materials, manure, and target crop seeds. They are hardy and can survive under most conditions and retain their viability in which other seeds cannot. To avoid such a scenario, only use clean seeds and sterilized planting materials.
Biological Weed Control Methods
Biological weed control methods are used to reduce the amount of weeds, but not to eliminate them in totality. It utilizes insects which feed on the weeds food reserves hence reducing their growth rate. Some insects also spawn on the weeds cutting off their supply of sunlight and moisture hence killing them gradually. Common examples of biological weed control methods include rhizoctonia blight which feeds on hyacinth and flea beetle which feeds on alligator weed.
Chemical Weed Control Methods
This is the application of industrial herbicides on weeds to kill or alter their growth. There are two types of herbicides, selective and non-selective. Non-selective herbicides kill all plants in their path while selective herbicides only target weeds. Herbicides toxicity is classified into four classes with the most toxic being class 1 and least toxic, class 4. Most non-selective herbicides are classified as class 1. Since they are very effective, this makes them a favourite with farmers.
Herbicides have a hazardous long term effect on the farm, people and animals. They are major contributors to polluted rivers, unfertile farms and chronic illnesses in humans. Most people have realized the negative effects of herbicides and are now shifting to more subtle, but effective weed control methods like mechanical control.
Mechanical control is defined as the act of removing weeds from the ground using machines. The machines could be as simple as garden hoes or complicated ones as precision hoes. The later has proved over and over again to be the best weed control method.
Weed control is a labor-intensive job, but with the advancements in technology, methods such as precision hoeing make it less labor intensive. Precision hoeing is the act of using a machine hoe mounted on a tractor to remove weed from a farm. The precision hoe has tine and blades each with equal spacing. Some precision hoes can have a span of more than 20m wide which runs across seven standard rows. When the GPS and precision hoe are set, a single person can efficiently weed out hundreds of acres in a day.
The precision hoe utilizes real-time kinetic-global position (RTK-GPS) tracking technology which determines the distance and direction it moves. The farmer presets the speed and maps out the direction in the GPS screen and satellite navigation does the rest. For it to work, the plants must be planted in a straight row devoid of any curves whatsoever. They must also have equal spacing between the rows. This ensures the precision hoe only digs up space in between the target crops.
To identify the weed, the machine utilizes high-resolution cameras mounted on the front and bottom. They distinguish weeds from other crops through spectral analysis and texture. Once a weed is identified, a high-speed blade cuts through the weed’s stem 6 cm down to the roots while a hoe at the back uproots the weeds. The blades only destroy the weed and do not damage the target crop. The precision hoe has a high affinity for accuracy such that it will not work when faced with weeding out target crops.
Weed control is a continuous process. As the world develops plants with superior features, so do weeds develop resistance to most control methods. To get the most out of each weed control method, it is recommendable to integrate several methods at a go. Begin with less damaging methods such as cultural and biological controls as you progress to mechanical and chemical weed control. It has been noted that precision hoeing is steadily gaining prominence over chemical weed control methods. This is attributable to its efficiency and zero toxicity.
(source : https://www.farmmanagement.pro/weed-control-and-precision-hoeing/ )