They are pretty close on the wind/sun/humidity issues.  Higher humidity can really reduce drying even if the wind is blowing. Sun in of itself isn't as important as air flow to move the air across/thru the windrow to dry the crop down. Heat is more important than stricktly sun.

Think of a Food dehydrator,, light is not a factor at all. heat to move the moisture to the outside of the food and wind to remove the moisture from the food surface.

"perfect hay drying conditions would be 80-90 degrees all night long with a 15 mph wind blowing across the field.

Wet ground is a factor in dry down also. Same issue which effects hay drying also effects the ground exactly the same way.  They made a very good point about stubble height, leave more stubble.  They were right too on the windrowing, wider the windrow the better conditions for air movement quicker drydown.

I will totally disagree with the article about baling moisture.  Levels approaching 14 percent in grass is going to be a train wreck for spoilage. Levels in the 18-20 percent in legumes,, same trainwreck. (I realize this may be a "here" issue,, but I don't sell hay 1/2 across the USA I sell it "here". )

Farmers need to realize,,,,  ANYBODY can buy a Moisture Tester and Dealers buy those moisture testers by the box load. Single largest factor in hay rejection aside from color (which just gets them close enough to the pile to ram in their mosture tester) is high moisture levels.

In grass I don't agree with the suggested settings for conditioners. I run the conditioner (double solid steel rollers with 3/4" x1 1/4" bars welded on) higher than the suggested spring settings of 600 pounds.  I have ran the spring at approximately 800 pounds for years. The rollers actually run in an interlocking fashion with about 1/8-1/4 inch between the rollers. (they almost touch in other words)  The conditioner is the single biggest draw on the HP as it works pretty hard to run the hay thru at those settings.

Realize those settings would likely knock every leaf off a legume. (but I'm not trying to get the moisture out of legumes)

Oh, drying agents,, nobody really uses them here although they work well. Customers will not buy hay that has drying agents in the bales.

A windrow turner does help drydown, by inverting the windrow and moving it off where it originally was placed in the windrow. The ground under the windrow is still wetter as the day the windrow was placed on it and the hay can "wick" up moisture from the ground. Inverting the windrow gives maximum exposure to wind and heat and a drier place for the windrow to set on.  The down side of course with wind and heat is "sun" which will bleach out the color faster. Some Growers will invert or turn over with a rake, others let the windrows lay for weeks with out touching at all.  The "untouched hay" looks much greener in the bale, hay gets turned inside during the baling process so the bale will be pretty and green. Downside of course is the inside of the bale is a lot browner and not nearly as nice looking.  Inverting or turning the windrows with a rake, may lose some leaves, if done at the wrong time of day, but the end resulting bale is a lot more uniform throughout the bale. Little browner on the outside but uniform from string to string.

Leaving a taller stubble will help. More stubble density helps to hold the windrows off the ground.  In timothy 3-4 inches is a superior cutting height compared to 2 inches as is mentioned in the article. The closer to the crown the longer it takes for the crown to recover and resume growing. (get the sickle bar out of the dirt, they are not field cultivators)

Just my experiences, results and observations "here", your results in your "area" may be very different.

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