By: Mark Sulc, Jason Hartschuh, CCA & Allen Gahler, Ohio State - 07/20/2021
The rainy weather in many regions of Ohio and surrounding states is making it
difficult to harvest hay crops. We usually wait for a clear forecast before
cutting hay, and with good reason because hay does not dry in the rain! Cutting
hay is certainly a gamble but waiting for the perfect stretch of weather can end
up costing us through large reductions in forage quality as the crop matures.
As we keep waiting for perfect haymaking weather, we will reach the point where
the drop in quality becomes so great that the hay has little feeding value
left. In such cases, it may be better to gamble more on the weather just to get
the old crop off and a new one started. Some rain damage is not going to reduce
the value much in that very mature forage.
Before cutting though, keep in mind that the soil should be firm enough to
support equipment. Compaction damage has long-lasting effects on hay crops.
We've seen many fields where stand loss in wheel tracks led to lower forage
yields, weed invasion, and frustrating attempts to "fill in" the
stand later.
This article summarizes proven techniques that can help speed up the process
involved in storing good quality forage. While the weather limits how far we
can push the limits, these techniques can help us improve the chances of
success in those short windows of opportunity between rains, and hopefully
avoid overly mature stored forages.
Consider making haylage/silage or baleage instead of dry hay. Haylage is
preserved at higher moisture contents, so it is a lot easier and quicker to get
it to a proper dry matter content for safe preservation compared with dry hay.
Proper dry matter content for chopping haylage or wrapping baleage can often be
achieved within 24 hours or less as compared with 3 to 5 days for dry hay.
"Hay in a day" is possible when making hay crop silage. The forage is
mowed first thing in the morning and laid in wide swaths to be raked in the
late afternoon and chopped as haylage starting in early evening. Proper dry
matter content for haylage ranges from 30 to 50% (50 to 70% moisture) depending
on the structure used.
Wrapped baleage usually requires 24 hours to cure. Wrapped baleage should be
dried to 40 to 55% dry matter (45 to 60% moisture).
Dry hay should be baled at 80 to 85% dry matter (15 to 20% moisture), depending
on the size of the bale package. The larger and the denser the dry hay package,
the drier it must be to avoid spoilage. For example, safe baling moistures for
dry hay without preservatives are 18-20% for small square bales (80 to 82% dry
matter), 18% or less for large round bales, and less than 17% for large square
bales. See below for more information on baling with preservatives.
Faster drying of cut forage begins with using a well-adjusted mower-conditioner
to cause crimping/cracking of the stem (roller conditioners) or abrasion to the
stems (impeller conditioners). Adjust roller conditioners so at least 90% of
the stems are either cracked or crimped (roller conditioners) or show some
mechanical abrasion (impeller conditioners).
Some excellent guidelines for adjusting these mower conditioners can be found
in an article by Dr. Ronald Schuler of the University of Wisconsin, available
online at https://bit.ly/3kCNAiJ
Desiccants are chemicals applied when mowing the crop that increase the drying
rate. The most effective desiccants contain potassium carbonate or sodium
carbonate. They are more effective on legumes than grasses and most useful for
making hay rather than silage or baleage. Desiccants work best under good
drying conditions. They do not help increase drying rate when conditions are humid,
damp, and cloudy, such as we have often experienced this summer. Consider the
weather conditions before applying them.
I once heard someone say "You can't dry your laundry in a pile, so why do
you expect to dry hay that way?"
Exposure to the sun is the single most important weather factor to speed
drying. The trick is to expose to sunshine as much of the cut forage as
possible.
The swath width should be about 70% of the actual cut area. The mowers on the
market vary in how wide a windrow they can make, but even those that make
narrow windrows have been modified to spread the windrow wider. Details can be
found in articles at the Univ. of Wisconsin website mentioned above (see
especially "Getting the Most from the Mower Conditioner" by Kevin
Shinners,
https://fyi.extension.wisc.edu/forage/getting-the-most-from-the-mower-conditioner/).
Another way to spread out and aerate the crop for faster drying is with a
tedder. Tedders are especially effective with grass crops. They can cause
excessive leaf loss in legumes if used when the leaves are dry. Tedders can be
a good option when the ground is damp, because the crop can be mowed into
narrow windrows to allow more ground exposure to sunlight for a short time, and
then once the soil has dried a bit the crop can be spread out with the tedder.
Tedding twice may decrease drying time. Tedding shortly after mowing allows
100% ground coverage, then tedding the next day helps keep the crop off the
ground. Be cautious to set tedder properly so that dirt is not incorporated
into the hay but all hay is lifted off the ground.
Take precautions to follow manufacturer recommendations on ground speed and
RPM's when tedding. Many of the modern in-line "fluffer" type tedders
are ground driven and operators often exceed recommended speeds, which can
result in bunching and wrapping of the hay, which will increase drying time and
make raking more difficult.
When making haylage, if drying conditions are good, rake multiple wide swaths
into a windrow just before chopping. For hay, if drying conditions are good,
merge or rake multiple wide swaths into a windrow the next morning when the
forage is 40 to 60% moisture to avoid excessive leaf loss.
Research studies and experience have proven that drying forage in wide swaths
can significantly speed up drying. Faster drying in wide swaths results in less
chance of rain damage and studies by the University of Wisconsin showed that
wide swaths (72% of the cut width) result in lower neutral detergent fiber
(NDF) and higher energy in the stored forage.
Sometimes the rain just comes quicker than we have time for making dry hay. As
mentioned above, making haylage helps us preserve good quality forage in those
short rain-free windows. A second option is to use a preservative. The most
effective preservatives are based on proprionic acid, which is caustic to
equipment, but many buffered proprionic preservatives are available that
minimize that problem.
Preservatives inhibit mold growth and allow safe baling at moisture contents a
little higher than the normal range for dry hay. Carefully follow the
preservative manufacturer's directions and application rates for the hay
moisture content at baling. Be sure the application is uniform to avoid spots
that spoil. Most products are effective when hay moisture is less than 25% but
become iffy between 25-30% and do not work if moisture is over 30%. When
utilizing preservatives, safe baling moisture can go up to 26% on small squares
and round bales, but only 23% on large squares, according to label guidelines
on most proprionic acid based products. Baling at these moistures requires
properly calibrated equipment to apply the correct amounts of preservative, and
it does not guarantee that bales will not generate internal heat.
While the acid works to limit the production of mold and fungal spores that can
lead to additional heating, any type of bale made over 20% moisture always has
the potential to heat. Although mold production may be limited, discoloration
and carmelization of the higher moisture stems can still occur. This heating
can also degrade proteins in the hay, reducing overall feed quality despite
still helping to preserving the hay from spoilage and hopefully making it safe
to store indoors. Keep in mind that preservative treated hay should be fed
within a year or less, as the preservative effect will wear off over time.
If baling on the wet side, watch those bales carefully! If hay is baled at
higher moisture contents that are pushing the safe limits, keep a close watch
on them for two to three weeks. Use a hay temperature probe and monitor the
internal temperature of the hay during the first three weeks after baling. See
the following article for more information on monitoring wet hay: https://bit.ly/3zcFGjZ