Jim - 1/30/2024 17:47

My #1 suggestion is to think in terms of pounds of hay rather than bales. People selling hay like to make 4x4 or occasionally 4x5 ft bales. These generally weigh anywhere from 700 to maybe 1000 lb.

A 4x4 bale has a volume of 50.28 cu ft, a 4x5 bale has a volume of 78.52 cu ft or 56% more than a 4x4, and a 5x6 bale has a volume of 141.35 cu ft or 281% (2.8 times) the volume of a 4x4.

Bale density is another variable.

My advice if you are buying or making your own hay is to think in terms of pounds or tons of hay rather than bales. 

I like feeding heavy, 5x6 bales in the winter as they require many fewer tractor starts in the winter than feeding lighter, smaller bales. Most hay feeders are also designed for 5x6 bales. I weighed a few bales on my cattle scale a few years ago and found my dry 5x6 bales weighed right around 1600 lb. I use 1500 lb/5x6 bale in calculations to account for waste or spoilage. I also will set the diameter at 70" rather than 72" to give me a bit of a cushion when stopping my 569 baler. For wet, wrapped bales, bale weight at wrapping is much heavier depending on the moisture when wrapped but I still figure them at 1500 lb of dry matter in each 5x6 bale. It all averages out and using 1500 lb per 5x6 bale works for me.

In your original question and assuming an average 1300 lb cow consumes 2.5% of her weight in dry hay per day:  2.5% x 1300 lb/cow x 25 cows = 812 lb dry hay required per day. (32.5 lb dry hay/day/cow) At 812 lb/day x 210 days that's 170,625 lb or 85.3 tons of hay to cover Nov 1 - June 1 for 25 average 1300 lb cows.  Or 114 of my 1500 lb 5x6 bales.

You can adjust for larger or smaller cows. Also once they calve, hay consumption goes up per cow that's calved.

If you're feeding 4x4's that's probably a bit more than a bale per day

If you're feeding 4x5's that's probably about 2 bales every 3 days

if  you're feeding 5x6's that's about 1 bale every 2 days

I've been overwintering cows on good (not prime) hay with Mineral-lyx barrels and white salt blocks for years. They don't need anything else except a good, non-frozen, water supply in my experience. I've tried adding silage and found it an unnecessary expense and that it was more productive to focus on raising good hay and pasture. Here I figure feeding hay 6 months but depends on the year.

Hope this helps.