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What are Three Ways of Removing Weeds from the Crop Field?
When we grow a food crop in the field, then in addition to the crop plants, many small, unwanted plants also germinate and grow in the field naturally. The unwanted plants (or wild plants) which grow alongwith a cultivated crop are called weeds (see Figure).
The growth of weeds in the fields is harmful because they consume a lot of fertiliser, water, sunlight and space, meant for the crop plants and reduce the crop yield, and lower the quality of food grains.
Since the presence of weeds in the fields will reduce the crop- yield, therefore, it is necessary to remove them from time to time. Though most of the weeds get uprooted during the ploughing of fields but they reappear when the crop grows. The weeds multiply and spread very fast because they produce a large quantity of seeds.
The type of weeds vary from field to field, from crop to crop, and also from season to season. Some of the common weeds (unwanted plants) found in wheat and rice fields are :
- Wild oat (Javi)
- Grass (Ghass)
- Amaranthus (Chaulai)
- Chenopodium (Bathua)
Since weeds are harmful to the crops, they must be removed from the fields. The process of removing weeds (unwanted plants) from a crop field is called weeding. Weeding is necessary because weeds compete with crop plants for water, nutrients, light and space, and hence affect the growth of the crop. Some weeds are poisonous for human beings and animals whereas some weeds interfere in harvesting.
The best time for the removal of weeds is before they produce flowers and seeds. Weeding is done by hand or with the help of implements like trowel (khurpa). Weeds can also be destroyed (or controlled) by spraying special chemicals called weedicides in the crop fields. Thus, the various methods of weeding (controlling weeds or eradicating weeds) are as follows:
1. Removal of Weeds by Pulling Them Out With Hand :
Weeds can be removed from the crop fields just by pulling them up with hands (see Figure). When we pull the weeds, they get uprooted from the.field. These uprooted weeds can then be thrown away.
2. Removal of Weeds by Using a Trowel (Khurpa) :
Weeds can be removed by digging or cutting them close to the ground from time to time with the help of an implement called trowel (or kizurpa). A trowel (or khurpa) is shown in Figure.
3. Destroying the Weeds by Spraying Special Chemicals Called Weedicides :
The poisonous chemicals which are used to kill weeds (unwanted plants) in the fields are called weedicides. Some of the common weedicides are : 2,4-D, MCPA and Butachlor. A solution of the weedicide in water is sprayed on the standing crops in the fields with a sprayer (see Figure).
The weedicides kill (destroy) the weeds (unwanted plants) but do not damage the main crop. The weedicides are sprayed in the crop fields before the flowering and seed formation in the weeds takes place. Since weedicides are poisonous chemicals, therefore, spraying of weedicides may affect the health of the person who handles the weedicide sprayer.
The weedicides should be sprayed on the standing crops very carefully. During the spraying of weedicides, the person should cover his nose and mouth properly with a piece of cloth (so as to prevent the inhaling of poisonous weedicide).