# Testing Hay Moisture



## downtownjr (Apr 8, 2008)

From my friends at Agratronix...

Why is it important to test hay moisture prior to baling?

Testing the moisture content of hay prior to the baling process is essential to both seller and buyer. Moisture in hay is considered in three different forms, free water, physically trapped water, and bound water. The free and physically trapped water can be evaporated given proper conditions which include solar radiation, relative humidity, and time.

At the time of baling the ideal moisture level is between 18 and 22 percent. Hay baled with higher moisture percentages can foster mold, resulting in loss, and in severe cases, damage as the accompanying heat can cause spontaneous combustion. Due to its importance, testing hay for moisture content is essential to the success for both the buyer and seller.

Prior to the invent of electronic testers, farmers would visually inspect the hay for moisture by picking up and subsequently breaking the stem to examine the moisture level in the stem to determine if it was ready for the baling process. Having the technology of electronic testers allows the farmers to pin point the ideal time for baling resulting in a higher overall yield from their fields. With the introduction of hand-held electronic testers, farmers not only have the benefit of accuracy they also have the benefit of efficiency.

Read the full article here:

http://www.agratronix.com/images/Testing_Hay_Moisture.pdf

Agtratronix meters are available atBale Supply - Welcome


----------



## Nitram (Apr 2, 2011)

Thank you this is now entered into my data base. I have read in another thread that the pressure will effect the readings. So how does one know how much pressure? Last yr was my first with Del. 2000 I checked in the windrow and in the bucket and found little variation. Then in the bale also similar readings. Is there a rule of thumb or is it trial and error? Martin


----------



## JD3430 (Jan 1, 2012)

Hay guys, if you could only afford one tester, which one would you get? 
I think I'm leaning towards the bucket tester since knowing the moisture before you bale seems better than knowing the moisture after it's going through the baler, right?


----------



## hay wilson in TX (Jan 28, 2009)

I'm leaning towards the bucket tester since knowing the moisture before you bale seems better than knowing the moisture after it's going through the baler, right? That would be the logical but no. 
BUT if you want an accurate moisture for your sample, use the Microwave system or the weighing of the sample and heating it in the supplied electric heater. 
Trouble is; By the time you have a moisture reading, conditions have changed.

Here is the problem. If you are thinking that during the day the Hay Moisture is steadily approaching the magic 18% and at that point it is safe to bale. 
Problem is the stems, even conditioned stems, dry at a slower rate than the leaves. Assume a 50-50 stem to leaf ratio. The average may be 18% but the leaves may be 10% and the stems still 26% moisture. Start baling and end up with 20% less hay due to leaf shatter, and essentially a bundle of damp stems.

What you want to do is have the hay cure down to where the stems are in the 10% moisture range. Maybe around supper time? 
Now if you are in the Arid West you will start to bale as the humidity gets up into the 65% range. We then assume the leaves are a nice damp 26% moisture, all surface moisture. The stems are still in the 10% moisture range and everyone is happy. 
In the Humid East we start baling as the morning humidity goes down through 70% and keep baling until we see excessive leaf shattering. This is probably in the 55% to 50% Humidity. This is humidity measured down at the hay level not at the Air Port or TV Station. A fairly accurate humidity meter is in the $150 range while a good enough for Dumb Me a $50 meter will do just fine.

*One Universal Truth for hay.*

Relative Humidity 
*90% RH *the hay will have no lower than 40% Moisture. 
The magic moisture for raking. 
*70% RH *the hay will be no lower than 18 to 20% Moisture The magic moisture for small square baling.
*65% RH *the hay will be no lower than 16 to 18% Moisture. The magic moisture for large bales. 
*55% RH* the hay in the 12% moisture range where leaf shattering becomes a major concern. 
The humidity we are talking about is down close to the hay, not free air humidity, not on TV and not at the Airport.

The devil is in the details and there are a number of details.

Cosider the Western Hay Farmer who needs to inject moisture into a windrow prior to baling to retain the leaves!


----------



## JD3430 (Jan 1, 2012)

I'm lost. My guess is no matter what I do it'll be too damp or too dry. 
How does one measure relative humidity near the ground where the hay is laying? 
One should quit baling before dew begins to fall, right?


----------



## Bob M (Feb 11, 2012)

JD3430, I live not to far from you in N.E. MD. I have found that moisture testers are only a guide. They are a wondeful tool, but I do not think you can take the art out of baling yet.I have a fairly inexpensive moisture tester in one of my balers as an extra tester, about $200. All my balers have the fully atuomated harvest tec system with the two star wheels on each side of chamber for moisture testing. I also use a koster tester, this a heated dring tool to test forage samples for our dairy. If done correctly the koster is correct. takes about an hour may be less with drier samples. I have found that the on the go testers will give you estimated moisture you still need to use other factors to determine when to bale. Here in the east I would highly reccomend using a perservitive on your hay, I use it on all of our hay no matter the moisture. Just seems to make better quality hay. If you are running baler yourself, and can do math on the go, a manuel this will work just fine. I think Paul B Zimmerman in Ephrata Pa. sells them.
Just my thoughts, there are many ways to make good hay.


----------



## Mike120 (May 4, 2009)

JD3430 said:


> I'm lost. My guess is no matter what I do it'll be too damp or too dry.


Not necessarily.....at some point in time, somewhere on your field, conditions will be perfect to make the ideal bale. You just may not be there at the time, so don't worry about it. Mr. Wilson's Universal Truths are probably as close to Hay Science as you're going to get. You can TRY to make perfect hay, but Mother Nature and the Weather Gods don't always communicate with each other. When it's time to cut and the forecasters say you have a period of dry weather you go make hay, using the equipment you've got, and hope for the best. More often than not, you'll get decent hay. All of us are adapting to average conditions in our locations and trying to have contingencies for when conditions move way out of average. It's never going to be perfect, so you might as well enjoy the variability as a challange. Otherwise, this would be pretty boring.



Bob M said:


> I have found that moisture testers are only a guide. They are a wondeful tool, but I do not think you can take the art out of baling yet.


Well said!


----------



## JD3430 (Jan 1, 2012)

Bob M said:


> JD3430, I live not to far from you in N.E. MD. I have found that moisture testers are only a guide. They are a wondeful tool, but I do not think you can take the art out of baling yet.I have a fairly inexpensive moisture tester in one of my balers as an extra tester, about $200. All my balers have the fully atuomated harvest tec system with the two star wheels on each side of chamber for moisture testing. I also use a koster tester, this a heated dring tool to test forage samples for our dairy. If done correctly the koster is correct. takes about an hour may be less with drier samples. I have found that the on the go testers will give you estimated moisture you still need to use other factors to determine when to bale. Here in the east I would highly reccomend using a perservitive on your hay, I use it on all of our hay no matter the moisture. Just seems to make better quality hay. If you are running baler yourself, and can do math on the go, a manuel this will work just fine. I think Paul B Zimmerman in Ephrata Pa. sells them.
> Just my thoughts, there are many ways to make good hay.


Bob,
Thanks for the help. I am probably more intimidated than I need to be, but it'll help me be respectful and more prepared for hay this year. 
I still haven't bought my round baler! 
One I'm looking at, a Deere 457 sileage, has an applicator system, but needs a new tank. 
I'm leaning towards this one, but have to admit, it's a reach for me on price. Maybe having parts of the preservative applicator there in place makes this one the one I should shoot for. 
Thanks for the great advice.


----------



## Waterway64 (Dec 2, 2011)

I was taught in alfalfa hay to use my thumb nail and scrape the courser part of the stem. If the green skin scrapes off it is to wet to bale. I have used a number of moisture testers over the years, both in the chamber and hand held, and they are only a guide. Buy one and then get some experience with it. If you are baling dry hay for example as the due sets, you may be able to bale hay at 22 to 23% readings because the due is setting on the outside of a dry plant and not in it. On the other hand if the due is burning off you may want to bale at say 14% because the plant has taken in moisture during the night. Remember that the meter only gives you a reading from that part of the plant it touches. Some good posts here!! Mel


----------

