Not sure why you would feed alfalfa hay to mature horses.  The extra cost of the alfalfa is probably not cost effective and could also cause kidney problems in an older horse. Being from the northeast, I'm not familiar with coastal grass hay. Is it the same as Bermuda grass?  I seem to remember a post years ago indicating impactions due to Bermuda grass, but can't remember the details.

If you could find a hay supply that's cheap enough, and you don't have room to store it at your home, perhaps you could look into renting a storage facility.  Cheaper price of the hay may make the extra cost of the storage unit or perhaps a POD a wash.

Just found this on Equisearch.com:

Did the Hay Cause Colic?
Can feeding Bermuda hay be linked to colic in this EQUUS reader's horse?

QUESTION: We've purchased round bales of coastal Bermuda grass to feed to our horses. They have been previously fed fescue hay and are used to it. About six weeks into the Bermuda--fed free choice--one of our horses colicked. Our veterinarian said it was because the Bermuda was so leafy that the horses eat it without having the need to drink as much water. Also, in the cooler months, the need for water drops. Both of these factors, the veterinarian said, increase the likelihood of colic. He said that fescue's characteristic tougher texture usually results in the horses taking in more water than if they just had Bermuda. I am confused about all of this. I have scheduled my spring plantings based on Bermuda, but I'm wondering if I should abandon these plans.

ANSWER: These types of questions are difficult to answer, primarily because so many factors can predispose a horse to colic. Coastal Bermuda grass round bales are used successfully in horse feeding programs all over Texas and in other southern states. Therefore, to say with certainty that the grass caused the colic is difficult.

If, however, the hay in the round bale was of questionable quality, several factors may have contributed to colic. For example, if the hay contained mold there is some chance the horse ingested enough to cause digestive upset. Other problems can occur when grass is extremely mature at baling. There is some evidence that the long-term intake of extremely indigestible fiber fractions can lead to impaction colic. And, without a doubt, inadequate water intake can disrupt moisture balance in the gut to the extent that colic can result. But is difficult to ascertain if the horse did not drink enough water because of diet or because of the quality or lack of availability of the water itself.

So, in short, I know of no published evidence that would cause alarm in my mind about providing round bales of coastal Bermuda grass hay, provided it is of good quality. To discourage them from ingesting too much in too little time, I would caution to avoid introducing such hay when the horses are extremely hungry. And remember that it is critical to ensure that the horses have access to a good water source.

hi Jakey.. coastal hay is coastal bermuda.. I guess I was typing so fast that I left that out.. Coastal bermuda is a fine-bladed hay that has potential for impaction due to the tendency for it to pack tightly in the gut.. I'm feeding a handful of alfalfa per day per horse just for the extra calories and protein.. My TWH I got in Jan of this year was very very thin and I've been trying to put weight on her (thus the DAC oil). Usually we don't have a problem putting weight on at our place, but as I stated we've had less than 2 inches of rain this year and very little last year.. Our place is just toast.  Even tho we placed the round bales at the front of the pasture right near the water troughs, the horses are reluctant to leave them to go get a drink.. Plus the freakin' wind is blowing all the time and everything is covered with dust..

I am going to buy @ 20 bales and store it in our garage, since we don't park the cars in there anyway.. i am keeping my girls up in their stall during the day and letting them eat hay..They'll go out at night.. The wind is not so bad at night also..

If you choose to feed alfalfa, make sure to ask where it came from and what cutting it is. Mid- Western States such as Texas, OK, and Kansas have three stripped blister beetles and could be baled in the hay. This could be deadly if your horse ate the beetles or even crushed beetle juice on the hay can cause death. I hate the SOBs!!!

First cutting is safer than 2nd or 3rd, but will be stemmier. 4th cutting is hit and miss on safety.

I also live in a high sand colic area. I don't feed free choice hay period. They get what they need for hay in their paddock from squares I feed twice a day. Alfalfa makes it worse if feed on the ground, or where the leaves can hit the ground. Horses will pic the bits up and ingest the sand even more. I personally hate free choice round bales of bermuda. Horse will just eat themselves straight to a colic, especially if you have a big eater. I feed Sandblaster 3 days in a row when I notice an issue. Most of the time I notice lose poop piles like a cow patty. If you dig in the pile you will see sand all inside it. One horse I have will not do this without the sandblaster. Her poop piles just get smaller and smaller. That is when I give her a round of sandblaster. My pasture is a mix of coastal bermuda and bahia (however you spell it). The bahia really helps keep them on the water.

Sand can be a really tough problem.  I solved mine by pouring a concrete pad 10 feet by 14 feet on which I placed my two-barrel feeder.  I put the hay in the in the open top of the feeder and the barrels catch the bulk of the leaves and fines.  The concrete keeps the horses from picking up sand as they vacuum the leaves and also keeps them from wearing mud holes around the trough.  I used plenty of wire in the concrete and rebar around the rim.  The concrete looks almost new after twenty years of hard use.   The fix was not as expensive back then as it would be today, but still cheaper than losing your best friend to sand colic.

Marla

     I had 3 horses colic last year because of a round bale and sand.  I almost lost my mare last year to impaction colic.  The suguron said it was a combination of sand and a dry round bale.   Now if something comes up my horses will just have to deal with some missed meal cramps till we get home, no more round bales for us.

     I use the scoop that came in the sand free bucket and feed one scoop of the generic metamucil every morning, and if I see one getting loose I check for sand and if I find it I feed 1 lb a day until I don't see any more sand and then 1/2 a lb a day untill the stools are normal again.  No need to wet it, they love it dry. I just add it to their morning feed or they will eat it dry out of my hand. We were having HORRIBLE problems with sand until I started this (on the vets recomendation). 

     Oh, and I've found that banamine doesn't work very well for sand colic pain(doesn't last very long) but the metamucil seems to really help.  The vet said it is because the psyllium coats the grains of sand so they aren't scratching/cutting the gut as they move.  I use 6 3lb containers a month for 5 horses, about $45 a month.

Yeap, this is basically what I do and it flat just works. Doing the poop patrol as I call it is necessary.

I just reading something about stemmy hay being more of a factor for impaction type colics than leafier hay. Stemmy hay is harder to digest and takes more water( for the gut) than lefty hay does. I'll have to try and find it again then I will post it for you.

That is what the vets said was wrong with my hay.  It was to mature and stemmy and was dry.  The horses simply wern't drinking enough to keep from getting impacted.  Two of my 3 were able to pass the hay with LOTS of IV fluid but the third had lots of sand in her and that is what made her colic case so much worse.  And she was/is my baby.

The leafy hay can be a problem here as well because the horses sift through the sand to find all the leaves.

My husband used to laugh at my "poop" obsession.  Now he askes if everything looks good.

If you ride your horse daily...stop the turn-out...since there is apparantly nothing for the horses to eat in the pastures...other than sand...

In FL, we control the consumption through management changes. These changes include feeding, both grain and hay, only out of feeders, feeding off the ground and using mats in the feeding area. These steps will all help to control the sand intake. When feeding outside in a dry lot or a sparsely vegetated pen or pasture, covering a large area with mats, will help control both the eating area and the surrounding area where the horse is likely to browse for every last morsel of hay.

These control measures helped us, yet in your situation in which it is either hard or impossible to control the consumption of sand including herd pasture management, dry-land pasture grazing, and various other housing arrangements, unless you are going to cut out turn-out for the foreseeable future...

For horses that do consume some quantity of sand, if complete control of sand intake is not possible, sand removal treatment with psyllium is a viable option. Historically there have been four problems with most psyllium treatments,

1.)not enough psyllium within the product administered,

2.) not enough product administered at each dosing,

3.) not a long enough or regular enough treatment period, and

4.) the lack of clearance due to altered colonic motility.

Good luck with your efforts...