Here is a list of implements used for the tillage of soil: 1. Plough 2. Tractor Drawn Implements 3. Harrow 4. Cultivators 5. Puddler 6. Bund Former 7. Ridger 8. Soil Scoop 9. Green Manure Trampler 10. Paddy Weeder 11. Hand Hoes and Hand Tools.
Implement # 1. Plough:
The main implement for primary tillage is plough used for ploughing operations. Ploughing is the primary tillage operation, which is performed to cut, break and invert the soil partially or completely. Ploughing, essentially means opening the upper crust of the soil, breaking the clods and making the soil suitable for sowing seeds.
The purpose of ploughing can be summarised as below:
1. To obtain a deep seed bed of good texture.
2. To increase the water holding capacity of the soil.
3. To improve soil aeration.
4. To destroy weeds and grasses.
5. To destroy insects and pests.
6. To prevent soil erosion and
7. To add fertility to the soil by covering vegetation.
Normal ploughing – It is the ploughing up to a depth of about 15cm.
Contour ploughing- It is the method of ploughing in which the soil is broken and turned along the contours.
Plough Accessories:
There are a few accessories necessary for ploughs such as:
1. Jointer
2. Coulter
3. Gauge Wheel
4. Land Wheel and
5. Furrow Wheel
1. Jointer:
It is a small irregular piece of metal having a shape similar to an ordinary plough bottom. It looks like a miniature plough. Its purpose is to turn over a small ribbon like furrow slice directly in front of the main plough bottom. This small furrow slice is cut from the left and upper side of the main furrow slice and is inverted so that all trashes on the top of the soil are completely turned down and buried under the right hand corner of the furrow.
2. Coulter:
It is a device used to cut the furrow slice vertically from the land ahead of the plough bottom. It cuts the furrow slice from the land and leaves a clear wall. It also cuts trashes which are covered under the soil by the plough.
The coulter may be of following types:
(а) Rolling Type Disc Coulter
(b) Sliding Type Knife Coulter
(a) Rolling Type Disc Coulter:
It is a round steel disc which has been sharpened on the edge and suspended on a shank and yoke from the beam. The edge of the coulter may be either smooth or notched. It is so fitted that it can be adjusted up-down and sideways. The up-down adjustment takes care of depth and sideways adjustment is meant for taking care of width of cut.
(b) Sliding Type Knife Coulter:
It is a stationary knife fixed downward in a vertical position on the beam. The knife does not roll over the ground but slides on the ground. The knife may be of different shapes, and sizes.
3. Gauge Wheel:
It is an auxiliary wheel of an implement to maintain uniform depth of working. Gauge wheel helps to maintain uniformity in respect of depth of ploughing in different soil conditions. It is usually placed in hanging position.
4. Land Wheel:
It is the wheel of the plough which rims on the un-ploughed land.
5. Front Furrow Wheel:
It is the front wheel of the plough which runs in the furrow.
6. Rear Furrow Wheel:
It is the rear wheel of the plough which runs in the furrow.
Adjustment of Mouldboard Plough:
For proper penetration and efficient work by the mouldboard plough, some clearance is provided in the plough. This clearance is called Suction of the plough.
Suction in mouldboard plough is of two types:
1. Vertical Suction, and
2. Horizontal Suction
1. Vertical Suction (Vertical Clearance):
It is the maximum clearance under the landside and the horizontal surface in the working position. It is the vertical distance from the ground, measured at the joining point of share and landside. It helps the plough to penetrate into the soil to a proper depth. This clearance varies according to the size of the plough.
2. Horizontal Suction (Horizontal Clearance):
It is the maximum clearance between the landside and a horizontal plane touching point of share at its gunnel side and heals of landside. This suction helps the plough to cut the proper width of furrow slice. This clearance varies according to the size of the plough. It is also known as side clearance.
Throat Clearance:
It is the perpendicular distance between point of share and lower position of the beam of the plough (Fig. 13.9).
Vertical Clevis:
It is a vertical plate with a number of holes at the end of the beam to control the depth of operation and to adjust the line of pull.
Horizontal Clevis:
It is a device to make lateral adjustment of the plough relative to the line of pull.
Plough Size:
The perpendicular distance from wing of the share to the line joining the point of the share and heel of landside is called size of plough. The size of the mouldboard plough is expressed by width of cut of the soil.
Implement # 2. Tractor Drawn Implements:
Tractor drawn implements possess higher working capacity and are operated at higher speeds. These implements need more technical knowledge for operations and maintenance work.
Tractor drawn implements may be:
(a) Trailed Type
(b) Semi-Mounted Type and
(c) Mounted Type
(a) Trailed Type Implement:
It is one that is pulled and guided from single hitch point but its weight is not supported by the tractor.
(b) Semi-Mounted Type Implement:
This type of implement is one which is attached to the tractor along a hinge axis and not at a single hitch point. It is controlled directly by tractor steering unit but its weight is partly supported by the tractor.
(c) Mounted Type Implement:
A mounted implement is one which is attached to the tractor, such that it can be controlled directly by the tractor steering unit. The implement is carried fully by the tractor when out of work.
Centre of Power:
It is the true point of hitch of a tractor.
Centre of Resistance:
It is the point at which the resultants of all the horizontal and vertical forces act. The centre lies at a distance equal to 3/4th size of the plough from the share wing.
Line of Pull:
It is an imaginary straight line passing from the centre of resistance through the clevis to the centre of pull (power).
Pull:
It is the total force required to pull an implement.
Draft:
It is the horizontal component of the pull, parallel to the line of motion.
D = P cos Ɵ
Where,
D = draft (kgf) and
P = pull in (kgf)
Ɵ = angle between line of pull and horizontal
In S.I. unit
Watt, W = Draft (N) x Speed (m/s)
Metric hp = Draft (kfg) x Speed (metres per second) / 75
Draft depends upon – (i) Sharpness of cutting edge, (ii) Working speed, (iii) Working width, (iv) Working depth, (v) Type of implement, (vi) Soil condition, and (vii) Attachments
Draft is of following two types:
1. Side Draft:
It is the horizontal component of the pull perpendicular to the direction of motion. This is developed if the centre of resistance is not directly behind the centre of pull.
2. Unit Draft:
It is the draft per unit cross sectional area of the furrow.
Theoretical Field Capacity – It is the rate of field coverage of the implement, based on 100 per cent of time at the rated speed and covering 100 per cent of its rated width.
Theoretical field capacity in hectares/hr:
= width (m) x speed (m/hr) / 10000
Effective Field Capacity- It is the actual area covered by the implement, based on its total time consumed and its width.
Field Efficiency – It is the ratio of effective field capacity and theoretical field capacity expressed in per cent.
Field Efficiency (ƞ) = Effective field capacity/Theoretical field capacity x 100
Effective field capacity is calculated as follows:
C = Width (m) x Speed (m/hr) / 10000 x ƞ
Where,
C = effective field capacity, hectare per hr.
Soil Inversion = x1 – x2 / x1 x 100
x1= No. of weeds before ploughing in a fixed area.
x2 = No. of weeds after ploughing in the same area.
Soil Pulverization- It is the quality of work in terms of soil aggregates and clod size. This is measured by penetrometer.
Animal Drawn M.B. Plough:
The main components of animal drawn M.B. plough are as follows:
1. Share:
It is that part of the plough which penetrates into the soil and makes a horizontal cut below the surface. It may be a single integral piece or may consist of replaceable parts. Share is usually made of chilled iron castings or steel with carbon content ranging from 0.5 to 0.8%.
2. Mouldboard:
It is that part of the plough which lifts, pulverises and inverts the furrow slice. It is usually made of mild steel or cast iron.
3. Landside:
It is that part of the plough which slides against the furrow walls and gives lateral stability in the plough.
4. Frog:
It is that part of the plough, to which other parts of the plough are attached such as landside, mouldboard and share.
5. Beam:
It is that part which transmits the power of the animal to the plough.
6. Standard:
The part connecting the soil cutting unit of the implement to the beam to which-the plough bottom and the handle is attached is called standard.
7. Gauge Wheel:
It is a small wheel needed for the control of the plough which has short beam.
Size of Plough:
On the basis of the size of the plough, it can be classified as:
(a) Light Plough – above 100 mm width but below 150 mm
(b) Medium Plough – 150 mm to 200 mm width
(c) Heavy Plough – 200 mm width and above.
The inclination of the share blade to the direction of travel is 30° to 45°. The horizontal suction varies from 3 to 12 mm and vertical suction varies from 6 to 20 mm, depending upon the size and the shape of the plough.
Animal drawn M.B. plough is of two types:
i. Fixed Type or One Way Plough and
ii. Reversible or Two Way Plough
i. Fixed Type (One Way) Mouldboard Plough:
One way plough throws the furrow slice to one side of the direction of motion and is commonly used everywhere; it may be long beam type.
ii. Two-Way or Reversible Plough:
It is a mouldboard plough which turns furrow slice to the right or left side of direction of travel as required. Such ploughs have two sets of opposed bottoms. In such plough, the entire furrow can be turned towards the same side of the field by using one bottom for one direction of travel and the other bottom on the return trip. Two sets of bottom are so mounted that they can be raised or lowered independently or rotated along an axis.
Two way ploughs have the advantages that they neither upset the slope of the land nor leave dead furrows or back furrows in the middle of the field. This type of plough is suitable for terraced land of hilly tracts.
It is useful for ploughing irrigated land also since it does not leave back furrows and dead furrows in the field. The disadvantage of this plough is that it is heavier and expensive compared to one way plough. Tractor drawn reversible ploughs are very effective in field operations.
Turn Wrest Plough:
There are some reversible ploughs which have single bottom with such an arrangement that the plough bottom is changed from right hand to left hand by rotating it through approximately 180° about a longitudinal axis. This type of plough is called turn wrest plough. While moving in one direction, the plough throws the soil in one direction and at the return trip the direction of the plough bottom is changed, thus the plough starts throwing the soil in the same direction as before.
This plough is capable of turning furrows either to the right or to the left side. It is very useful for ploughing along hillsides, where it is necessary to turn all furrows downhill due to slope of the land. On levelled surface also this plough has proved to be useful.
Ploughing of Land:
The ploughing of land separate the top layer of the soil into furrow slices. The furrows are turned sideways and inverted to a varying degree, depending upon the type of plough being used. It is a primary tillage operation, which is performed to shatter soil uniformly with partial or complete soil inversion.
There are a few important terms frequently used in connection with ploughing of land:
1. Furrow:
It is a trench formed by an implement in the soil during the field operation.
2. Furrow Slice:
The mass of soil cut, lifted and thrown to one side is called Furrow slice.
3. Furrow Wall:
It is an undisturbed soil surface by the side of a furrow.
4. Crown:
The top portion of the turned furrow slice is called Crown.
5. Back Furrow:
A raised ridge left at the centre of the strip of land when ploughing is started from centre to side is called back Furrow. When the ploughing is started in the middle of a field, furrow is collected across the field and while returning trip another furrow slice is lapped over the first furrow. This is the raised ridge which is named as back furrow.
6. Dead Furrow:
An open trench left in between two adjacent strips of land after finishing the ploughing is called dead furrow.
7. Head Land:
While ploughing with a tractor, a strip of unploughed land is left at each end of the field for the tractor to turn, that is called Head land. At the end of each trip, the plough is lifted until the tractor and the plough have turned and are in position to start the return trip. The head land is about 6 metres for two or three bottom tractor plough and one metre more for each additional furrow.
Methods of Ploughing:
In order to provide furrows at all times on the right hand side of the plough, two methods of working are used:
1. Gathering
2. Casting
1. Gathering:
Whenever a plough works round a strip of ploughed land, it is said to be gathering.
2. Casting:
Whenever a plough works round a strip of unploughed land, it is said to be casting.
Ploughing of a field by casting or gathering alone is normally uneconomical.
The following are a few important methods used in tractor ploughing:
(а) Continuous Ploughing Method and
(b) Round and Round Ploughing
(a) Continuous Ploughing Method:
In normal conditions, the continuous ploughing method is considered very convenient and economical. This is a method usually used in which the tractor and plough never run idle for more than three quarter land width along the headland and never turn in a space narrower than a quarter land width. In this method, first the headland is marked and the first ridge is set up at three quarter of a land width from the side. The other ridges are set at full width over the field.
The operator starts ploughing between the first ridge and the side land. The operator continues to turn left and cast in the three quarter land until a quarter land width of ploughing is completed on each side. At this stage, it is important to lift the plough to half depth for last trip down the side land of the field. This leaves a shallow furrow where the finish comes.
After this, driver the turns right and gathers round the land already ploughed on the first ridge. Gathering is continued till the unploughed strip in first three quarter land has been ploughed and completed. This gathering reduces the first full land by a quarter. The remaining three quarter land can be treated in exactly the same manner as the original three quarter land. This process is repeated for all other lands in the field.
(b) Round and Round Ploughing:
In this method, the plough moves round and round a field. This system is adopted under conditions where ridges and furrows interfere with cultivation work.
The field can be started in two ways:
(i) Starting at the Centre:
A small plot of land is marked in the middle of the field and it is ploughed first. After that, the plough works round this small plot and the entire plot is completed. This is not a very economical method.
(ii) Starting at the Outer End:
Tractor starts ploughing at one end of the field and then moves on all the sides of the plot and comes gradually from the sides to the centre of the field. Wide diagonals are left unploughed to avoid turning with the plough. There are no back furrows in this method. Conventional ploughing is usually done by this method.
One Way Ploughing:
This system requires the use of a special type of plough known as reversible plough or one way plough. Such a plough turns furrows to the left or right. After the headland has been marked, the operator ploughs along a straight side land mark. At the end of the first trip, he turns his tractor in a loop and returns down the same furrow. No dead and back furrows are left in the field. In gently sloping fields, this method is suitable.
Implement # 3. Harrow:
A harrow is an implement that cuts the soil to a shallow depth for smoothening and pulverising the soil as well as to cut the weeds and to mix materials with soil. It is an implement used to break the clods after ploughing, to collect trash from the ploughed land and to level the seed bed.
Implement # 4. Cultivators:
It is an implement for inter cultivation with laterally adjustable tines or discs to work between crop rows. This can be used for seed bed preparation and for sowing with seeding attachment. The tines may have provision for vertical adjustments also.
The cultivator can be of following types:
1. Disc Cultivator:
It is a cultivator fitted with disc
2. Rotary Cultivator:
It is a cultivator with tines or blades mounted on a power driven horizontal shaft.
3. Tine Cultivator:
It is a cultivator fitted with tines having shovels.
The cultivator stirs the soil, and breaks the clods. The tines fitted on the frame of the cultivator comb the soil deeply in the field. A cultivator performs functions intermediate between those of plough and the harrow. Destruction of weeds is the primary function of a cultivator.
The following are a few important functions performed by a cultivator:
(a) Interculture the fields.
(b) Destroy the weeds in the field.
(c) Aerate the soil for proper growth of crops.
(d) Conserve moisture by preparing mulch on the surface.
(e) To sow seeds when it is provided with sowing attachments.
(f) It prevents surface evaporation and encourages rapid infiltration of rain water into the soil.
Implement # 5. Puddler (Animal Drawn):
It is an implement used for churning the soil in standing water. Puddler is used for preparation of paddy fields with standing water after initial ploughing. It breaks up the clods and churns the soil. The main purpose of puddling is to reduce leaching of water, to kill weeds by decomposing and to facilitate the transplanting of paddy seedlings by making the soil softer.
Puddling is done in standing water of 5 to 10 cm depth. A common puddler used in this country has three puddling units, each having four paddles mounted on an axle. The axle with the puddling units is freely mounted on two bearings, fitted on a frame, made of metal or wood. The weight of the puddler including its beam is within range of 30 to 40 kg only.
The puddler consists of:
a. Frame
b. Paddles
c. Metal Cross
d. Handle
e. Beam
Implement # 6. Bund Former:
It is used for making bunds or ridges by collecting the soil. Bunds are required to hold water in the soil, thereby conserve moisture and prevent run off. The size of the bund former is determined by measuring the maximum horizontal distance between the two rear ends of the forming boards.
Bund former consists of:
a. Forming board
b. Beam
c. Handle
Implement # 7. Ridger (Animal Drawn):
It is an implement which cuts and turns the soil in two opposite directions simultaneously for forming ridges. It is also known as furrower. Ridger is used to form ridges, for sowing row crop seeds and plants in well tilled soil. The ridger is also used for forming field furrows or channels, earthing up and similar other operations. Ridgers are also known by the names ridging plough and double mouldboard plough.
The ridger generally has V-shaped or wedge-shaped share, fitted to the frog. The nose or the tip of the share penetrates into the soil and breaks the earth. The mouldboards lift, invert and cast aside the soil, forming deep channels and ridges of the required size. A ridger consists of beam, clevis, frog, handle, mouldboards, braces, share, and sliding shoe.
Implement # 8. Soil Scoop (Animal Drawn):
Soil scoop is used in excavating ditches, cleaning drains and moving soil over short distances.
It consists of:
a. Blade
b. Soil Trough
c. Hitching Loop and
d. Handle
a. Blade:
Blade is made of high carbon steel with carbon content varying between 0.5 to 0.6%. The angle of the cutting blade varies from 12° to 15° only. The blade is riveted or bolted to the soil trough.
b. Soil Trough:
It is made of mild steel sheet. It has two handle holders when wooden handles are to be inserted.
c. Hitching Loop:
Two ends of the loop are fitted to the sides of the soil trough. The loop is made of mild steel round.
d. Handle:
There are two handles made of timber or mild steel flat.
Implement # 9. Green Manure Trampler (Animal Drawn):
It is an implement used to trample and press the green manure crop in the fields.
There are two types of trampler:
a. Slat type and
b. Disc type
In slat type trampler, long radial slats are fixed to the central axle through the supporting disc. In disc type trampler, flat discs are fixed to the centre axle. The size of the trampler is its maximum working width. The weight of the green manure trampler (without beam) lies between 30 kg to 40 kg only.
The main parts of the trampler are- a. Frame, b. Axle and bearings, c. Disc or slat, d. Foot board and e. Handle
Implement # 10. Paddy Weeder:
Paddy weeder is important equipment for interculture, used in paddy cultivation. Improved varieties of paddy crops are grown in rows and to keep down the weeds, this weeder is used. It is used for uprooting weeds and burying them in puddled soil between rows of standing paddy crop. It improves the aeration of soil.
It consists of:
a. Frame
b. Weeding Roll
c. Tines
d. Float and
e. Handle
Implement # 11. Hand Hoes and Hand Tools:
I. Hand Hoe:
It is a hand tool with blade(s), tine(s) and sometimes disc(s) attached to a frame, used for inter-cultivation of crop.
II. Spade (Kodali):
It is a hand tool comprising a narrow blade and a wooden handle used for loosening and cutting the soil.
III. Khurpa:
It is a hand tool comprising a blade and short handle used for loosening the soil and weeding.
Different types of hand hoes are used in different parts of the country. The shape and size of hoes vary from place to place.
IV. Wheel Hoe:
It is a hoe with one or two wheels. Wheel hoe is used for interculturing purposes in between rows of crops. There is a wheel attached to the two handles, to which a working tool is attached. Wheel is helpful in guiding the tool and maintaining proper depth. It is useful for kitchen gardens. It consists of wheel, axle, frame, and working tool.
Some Miscellaneous Equipments:
i. Post Hole Digger:
It is used for digging holes for tree plantation. It consists of an auger which is operated by pto of the tractor through a gear drive mechanism.
ii. Hydrodozer:
It is used for land shaping and field terracing. It is mounted in front of tractor. The dozing blade is hydraulically controlled. The blade is made of hardened alloy steel and is reversible type. It may be run by 50 hp tractors or above. The blade height ranges from 58 cm to 65 cm and blade length may be about 200 cm.
iii. Ditcher:
It is used for making drainage ditches. It is coupled to the tractor with 3 point linkage system and is controlled by the hydraulic system of the tractor. It penetrates into the soil due to suction and its own weight and is drawn behind the tractor. It slices the soil to the side thereby forming a ditch.
iv. Cultipacker:
Its function is breaking of clods and packing of soil thereby conserving the moisture. It consists of a number of cast iron rollers mounted on an axle. Sometimes it can be attached behind the disc harrow (trailing type) to affect complete moisture preservation.
v. Shrub Cutter:
It is used for cutting crop stubbles, grass and lawn mowing. It is a tractor drawn implement consisting of rotary cutting knives driven by pto of the tractor. The blades are replaceable type and are made from heat treated steel. The width of cutting may be 140 cm and cutting height may vary from 2 to 40 cm. It may be operated by a 30 hp tractor and above.
vi. Blade Terracer (Tractor Mounted):
It is used for land levelling purpose. It is attached to the tractor by the 3 point linkage system and is hydraulically controlled. It is fabricated from steel and can be quickly adjusted for angle and pitch of the blade. It can also be reversed for back filling.
vii. Hydraulic Scraper:
It is used for rough levelling, cutting of high spots and filling of depression. It is towed behind the tractor. Its working is controlled by the hydraulic arrangement. As the tractor moves forward the blade penetrates into the soil and fills the bucket. After that, the scraper is moved to the point of unloading. For unloading, the bucket is tilted hydraulically. It can be operated by 50 hp tractor or above. The cutting blade width may be 150-120 cm.