Vaderstad RAPID RDA S Series, Instructions Manual

Page: 68 / 122

Advice on sowing
68 Ver.2 01.11.2002
4 Advice on sowing
4.1 Sowing depth
Figure 4.1
See
”3.7 Adjusting sowing depth” on page 31
and
”3.8 Adjusting weight transfer” on page 32.
The most important task for the Rapid operator is to carefully and continually check the sowing
depth. The sowing depth is set using the depth stop on the lifting ram. The numbers on the scale
do not represent absolute values of sowing depth in centimetres. Rather, they should be seen as a
guide.
The Rapid seed drill can be used under a great variety of conditions, ranging from direct drilling
to sowing directly after ploughing. This is possible thanks to the design of features such as the
coulter system and the unique depth control system.
Sowing depth must adapted to suit the crop, the soil type and the soil conditions at the time of sow-
ing. Shallow sowing depths require very good conditions for germination in terms of moisture and
fineness of tilth, especially on e.g. silty soils. Sowing too deep can give rise to weakened seed-
lings.
On fields with varying soil type, sowing depth should be checked and adjusted continually to en-
sure that the correct sowing depth is maintained throughout the field.
Sowing depth must be adjusted with the aim of placing the seed in moist soil, yet not too deep.
The correct preparation of the tilth prior to sowing is essential for producing the right conditions
for germination.
Sowing depth should be checked regularly during the day, for example after every 4 hectares or
once an hour. Check the sowing depth midway between the tractor tracks, within a tractor track,
and behind the left and the right wing sections. If the sowing depth of the wings is different from
that of the centre section, the function and settings of the hydraulic system must be checked. This
includes e.g. the weight transfer to the wing sections. The tool bars may require greater weight
transfer on hard ground. When sowing small seed in loose soil, the weight transfer may need to be
reduced.
Check with equal regularity that the depth stop for setting sowing depth has remained in place. If
the depth stop has moved, it is normally not sufficient to try to tighten it. The depth stop should
only be tightened very lightly.