Q.4 Write a paragraph in your own words on each of the following.
(a) Preparation of soil (b) Sowing (c) Weeding (d) Threshing

(a) Preparation of soil:
The first step before growing crops is preparation of the soil. So the soil is first prepared to help in better growth of the crops. As we know that roots play a vital role in the proper growth of a plant/crop, so its necessary to make the soil ready before sowing of seeds. Preparation of soil includes ploughing which gradually loosens the soil so that it can hold nutrients and water. These nutrients and water are transported to the crop through their roots. Loosening of soil also helps the root to penetrate deep into the soil and help the soil microbes and earthworms to grow in the soil so that they can feed on plant debris(dead roots, leaves, grasses, manure). Their excreta contributes a lot for the nutrition of plants and when their body decompose it further contributes to the nitrogen content of soil.

(b)Sowing:
Sowing is the process of scattering of seeds in an order, in or on the soil. Good quality seeds are used for sowing as it will help in a good yield. So there is pre-treatment of soil before sowing which includes seed cleaning with medium hot water for atleast 24 hours to upto 48 hours. Seed cleaning is done in case of fruits as the flesh around the fruits can make the seed prone to insect attack. Sowing is usually done with the help of either a traditional tool or a seed drill. The traditional tool is shaped like a funnel. Nowadays, seed drills that make the use of tractors are used for sowing seeds. This tool disperses seeds uniformly and sows seeds at a proper depth. Sowing by this method saves time and also protects the seeds from birds.

(c) Weeding:
Removal of unwanted plants from the field is called as weeding. Weeds compete with crop plants for nutrients and water. Thus it will reduce the yield of the desired crops. Weeds also interfere while harvesting and gets mixed with crops. Some weeds are poisonous to animals and humans. Tilling is a common method which helps in the removal of weeds before sowing crops which includes manual methods like physical removal of weeds. Weedicides are sprayed to get rid of weeds, but this method may affect the health of farmers because of the chemicals that are used in weedicides.

(d) Threshing:
The process of separating the chaff from the crop is known as threshing. It loosens the edible part of the grain from the straw to which it is attached. Threshing is carried out by a thresher. A machine called ‘combine’ which is a harvester that performs 4 separate harvesting functions that includes reaping, threshing, gathering and winnowing. Threshing is also done by winnowing where blow of wind is used to separate the chaff from crops.