Seeding or sowing is an art of placing seeds in the soil to have good germination in the field. A perfect seeding gives correct amount of seed per unit area, correct depth at which seed is placed in the soil, correct spacing between row-to-row and plant-to-plant. Broadcasting is the process of random scattering of seed on the surface of seedbeds. It can be done manually or mechanically both. When broadcasting is done manually, uniformity of seed depends upon skill of the man. Soon after broadcasting the seeds are covered by planting or some other devices. Usually higher seed rate is obtained in this system. Mechanical broadcasters are used for large-scale work. This machine scatters the seeds on the surface of the seedbed at controlled rates. Broadcasting the seeds by drones will create huge impact that is it makes the process of broadcasting easier. Broadcast sowing is a traditional way of planting many types of crops. It’s simpler, faster, and easier than traditional row sowing and works best for plants that do not require singular spacing or that are more easily thinned later. Most grains, grasses, and shallow-rooted annuals are broadcast spread.
The smallest are handheld with a hopper of several litters and which operate via hand cranking. A bit larger are push units with the spinning disk powered by gearing to the wheels. The next size up is designed to be towed behind a garden tractor. Very similar in size to the tow behind units are broadcast speeders that mount to the three-point hitch of a compact utility tractor, these are ideal for landscape and small property maintenance. Still larger are commercial broadcast speeders/spreaders designed and sized appropriately for agricultural tractors and mount to the tractor’s three-point hitch. The broadcast speeders that are mounted to a three-point hitch are powered by a power take-off (P.T.O.) shaft from the tractor. At the largest size are pull behind or chassis mounted units for agricultural use that can spread widths of up to 90 feet.
BENEFITS OF BROADCAST SOWING
Besides being an easier way to sow seeds, broadcast sowing also enables the gardener to spread very fine or small seeds over a relatively large area. Individually planting large numbers of tiny-seeded plants–carrots and lettuce, for example–is tedious at best, even with specialized tools.
Another great advantage is its ease of use for planting cover crops, grains, grasses and similar plants that don’t require row gardening or are meant to cover an area.
PLANTS SUITABLE FOR BROADCASTING
Nearly all plants can do well when it is broadcasted. The outcome of this method will depend upon the crop in question and the type of gardening being done.
List of common plants and the garden types they are best broadcast within:
- Beets – in square foot, container or raised bed gardening where sprouts can be easily thinned.
- Carrots – in square foot, container, or raised bed gardening where the sprouts can be easily thinned.
- Grains – in all situations, as grains thrive when grown as a grass, covering an area.
- Herbs – most types of herbs, such as chives, parsley, and cilantro are good choices for broadcast sowing no matter the garden type.
- Lettuce – in square foot, container, or raised bed gardening as well as in traditional row gardening where rows are easily broadcast towards (or created via broadcast, see below). Headed (non-loose leaf) will require thinning.
- Cover Crops – All types of cover crops (i.e. grasses, clovers) for protecting soil are best when broadcast sown.
SEED METERING MECHANISM
The mechanism of a seed distributor which delivers seeds or fertilizers from the hopper at selected rates is called seed metering mechanism. Seed metering mechanism may be of several types:
(a) Fluted feed type – It is a seed metering device with adjustable fluted roller to collect and deliver the seeds into the seed tube. Fluted feed type mechanism consists of a fluted wheel, feed roller, feed cut-off and adjustable gate for different sizes of grains. The feed roller and the feed cut-off device are mounted a shaft, running through the feed cups. The roller carries grooves throughout its periphery. It rotates with the axle over which it is mounted throws the grains out on the adjustable gate from where it falls into the seed tube. The fluted rollers which are mounted at the bottom of the seed box, receive seeds into longitudinal grooves and pass on to the seed tube through the holes provided for this purpose. By shifting the fluted wheel sideways, the length of the grooves exposed to the seed can be increased or decreased and hence the amount of seed is controlled.
(b) Internal double run type – It is a seed metering device in which the feed wheel is provided with fine and coarse ribbed flanges. It consists of discs, mounted on a spindle and housed in a casing fitted below the seed box. It has double faced wheel. Internal double-run type roller one face has a larger opening for larger seeds and the other face has smaller opening for smaller seeds. A gate is provided in the bottom-of the box to cover the opening not in use. The rate of seeding is varied by adjusting the speed of the spindle which carries the discs.
(c) Cup feed mechanism – It is a mechanism consisting of cups or spoons on the periphery of a vertical rotating disc which picks up the seeds from the hopper and delivers them into the seed tubes. It consists of a seed hopper which has two parts. The upper one is called grain box and the lower one is called feed box. The seed delivery mechanism consists of a spindle, carrying a number of discs with a ring of cups attached to the periphery of each disc. The spindle with its frame and attachment is called seed barrel. When the spindle rotates, one disc with its set of cups rotates and picks up few seeds and drops them into small hoppers. The cups have two faces, one for larger seeds and the rate at which the seed barrel revolves.
(d) Cell feed mechanism – It is a mechanism in which seeds are collected and delivered by a series of equally spaced cells on the periphery of a circular plate.
(e) Brush feed mechanism – It is a mechanism in which a rotating brush regulates the flow of seed from the hopper.
(f) Auger feed mechanism – It is a distributing mechanism, consisting of an auger which causes a substance to flow evenly in the field, through an aperture at the base or on the side of the hopper.
(g) Picker wheel mechanism – It is a mechanism in which a vertical plate is provided with radially projected arms, which drop the large seeds like potato in furrows with the help of suitable jaws.
(h) Star wheel mechanism – It is a feed mechanism which consists of a toothed wheel, rotating in a horizontal plane and conveying the fertilizer through a feed gate.
COMPONENTS OF BROADRONES
- Hopper or seed chamber
- Broadcasting plate
- Supporting boom
- Dc motor
- Servo or regulator
- Conveyor tube
WORKING OF BROADRONE
The basic operating concept of BROADRONE is simple. A large material hopper is positioned over a horizontal spinning disk, the disk has a series of 3 or 4 fins attached to it which throw the dropped materials from the hopper out and away from the seeded/spreader. Alternately a pendulum spreading mechanism may be employed, this method is more common in mid-sized commercial spreaders for improved consistency in spreading. Hoppers are commonly made of plastic, painted steel, or stainless steel. Stainless steel is usually used in large commercial units for strength and because granular fertilizer is often quite corrosive. Spreaders have directional fins to control the direction of the material that is thrown from the spreader. Broadrones require some form of power to spin the disk which uses a 12-volt motor to spin the dispersing disk.