Grain Guide 2018

Steps to calibrate planters Successful cropping has developed into a highly specialised process. Planters play an extremely important role in the process – particularly with respect to the accurate spacing of plants and the plant depth of seed. The accurate dispensing of fertiliser is also important. A planter has the following basic functions:  It opens the fertiliser furrow up to the correct depth for fertiliser placement.  Correct measuring of calibrated fertiliser and placement.  It opens the seed furrow up to the correct depth for seed placement.  Correct measuring and placement of seed.  Closing of seed and fertiliser furrows.  Compaction of the soil for effective soil to seed contact. The above functions must all take place simultaneously and their effectiveness should not be speed sensitive. The primary function of planters is to dispense seed correctly. Seed can be dispensed in the following ways:  Conventional horizontal tray dispenser  Tray dispenser dispensing at an angle  The finger-wheel dispenser  The vacuum tray dispenser Tray dispensers are still used, but because seed grading is no longer that accurate, vacuum dispensers and finger- wheel dispensers are used increasingly. Fertiliser is dispensed as granules or in liquid form. Granular fertiliser is dispensed positively with a star-wheel or worm dispenser. Liquid fertiliser is dispensed with a squeeze pump, or – these days – with a special liquid fertiliser pump. 1 3 2  The function of a planter  Dispensing and placement of fertiliser  Seed dispensing 37 34 GRAIN GUIDE 2018 Seed