Rit Búvísindadeildar - 20.11.1995, Page 41

The effect of conditioning
on the wilting rate of grass for silage
Bjarni Guðmundsson
SUMMARY
In this paper, results from a series of trials assessing the effects of mower
conditioners in improving the wilting rate ofgrassfor big bale silage in Iceland, are
reported. The swards were both mixed grass swards and pure stands. The mower
conditioners used were Deutz-Fahr SM324 and Krone AM 242/Z. Following
conclusions were made:
• Conditioning reduced the effective wilting time by 20%. Under Icelandic weather
conditions, this dijference can be crucial whether the crop reaches the desired DM-
levelfor baling a day sooner or later.
• Conditioning reduced the needfor spreading the crop immediately after cutting.
However, mowing/conditioning followed by an effective spreading gave thefastest
wilting rate, indicating that swath structure inhibits Jull potential ofthe conditioning
from being realised.
• The positive effects of conditioning decreased with increasing DM-yield and under
less favourable weather conditions. There seemed to be a positive interaction
between conditioning effect on the wilting rate and the swath/cutting-with ratio.
• The improving effect of conditioning on the wilting rate was not significantly
affected by the conditioning stage. On the other hand, measurements indicated that
rough conditioning increased the possibility ofhigh DM losses.
• Conditioning had no significant effect on the crude protein content or the
digestibility ofthe crop at baling.
• Conditioned material (timothy) with 33% DM baled approximately 18% tighter
than unconditioned material in aflex-chamber big baler.
• The difference between the conditioners tested with respect to the wilting rate
improvement was insignificant.
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