Multiva Optima T Series, Operation And Maintenance Manual, Page: 16 / 41

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4. USE AND ADJUSTMENT OF THE HARROW
Depending on the model of the harrow, some of the equipment mentioned in this manual are
installed as standard and some are available as options.
4.1. Seedbed preparation
The Multiva Optima T s-tine harrows are designed to perform seedbed preparation of soil, to which
primary tillage has already been carried out, to prepare the soil for seeding. The harrow is used to
loosen and crumble the soil to achieve a sufficiently fine result. The requirements for the even and
optimal growth of the cultivated plant include a seedbed that is as even as possible and the correct
surface crumb structure. An even seedbed is also important for the depth-holding of the seeder's
coulters.
The tillage effect is determined by changing the working depth, number of tillage rounds, number of
tillage times, tillage speed and directions as well as the tillage intensity of the levelling boards and cage
roller.
The correct tillage depth is the depth of sowing for the plant. On clay and silt soils, there must be a
sufficient amount of fine crumbs on top of the soil. This layer of crumbs forms a barrier against
evaporation, preventing the excessive drying of the soil. The surface of the seed layer must have larger
crumbs. They reduce the risk of slaking and maintain the seedbed loose. Particularly on silt soil, the
surface layer should not be tilled excessively fine. The primary objective of seedbed preparation of
easily cultivated sand, mull and peat soil is to level the soil for seeding.
In favourable conditions, the
Multiva s-tine harrow may only need one tillage run. However, the number
of tillage passes must always be selected according to conditions. If several tillage passes are carried
out, the run directions should be made perpendicular to each other. This ensures the maximum
evenness of the seedbed.
The suitable tillage speed for the operation of the s-tine and rear harrow is, depending on the
conditions, 8 – 12 km/h. With excessive tillage speed, the tillage characteristics of the s-tine suffer.
NB! Optima T s-tine harrow should not be used for the primary tillage of unprepared soil.
4.2. Tillage technique
Suitable tillage technique is influenced by several factors, e.g. the size and form of the block and
direction of seeding. Correctly selected tillage technique reduces required work and ensures the best
possible result. If several tillage passes are made, the last pass should be performed in the intended
direction of seeding. This reduces unnecessary tilting of the seeder unit. If possible, it is recommended
to drive parallel to the longest side of the block to minimise the time spent on turning.
Turn the wide harrow smoothly or rise it up a bit when turning around at the end of a field strip.
Do not reverse the harrow while the tines are in the soil.