I wanted to share my experience with grazing an old hay field in southern Iowa, since grazing alfalfa can be death-defying for some ungulates. This hay field is approximately 5 years old and is roughly half alfalfa and half orchard grass.  After doing a bunch of research and figuring out what promotes bloat from alfalfa and what doesn't, I decided to try grazing it since land is very hard to come by and hay is abundant in my area. Grazing this old hay field allows me to run more cattle, but I have to purchase hay in exchange, which isn't a big deal because hay is abundant and reasonably priced on most years.

The last 2 years I have waited to graze the field until the alfalfa is in full bloom, which usually happens around the 5th of June.  Waiting until the alfalfa blooms basically eliminates any chances of bloat, but it lacks nutrient  quality.  A plus to waiting till June to graze, is the alfalfa is waist deep and the orchard grass is arm pit deep, which allows me to trample a lot of the forage and really build some soil.

I grazed it a 2nd time in September, after it had around 90 days of rest. This time the alfalfa and orchard grass were approximately 12 inches tall, but not in bloom since both plants had already gone to seed back in June.  I checked on the herd several times after turning them into the field, since the alfalfa was not in bloom and it was a cloudy rainy day.  I had 3 bloat causing factors working against me.  Not in bloom and a lack of sunlight increases the protein level of the plant and makes it more prone to bloat.  Also the added moisture on the plant makes it more digestible and more prone to bloat.  I didn't have any issues with bloat and I believe it was because the plant was fully mature with 90 days of rest, even though it was not in bloom and the field is only 50% alfalfa.   

Fast forwarding to the end of October, the field has had about 50 days of rest and is in the same state as it was in September.  Alfalfa and orchard grass are about 12 inches tall, but not in bloom. About 2 weeks into grazing the field, the weather man tells me that its supposed to get down below 28 F for 2 nights in a row. A hard frost will rupture the cell walls of alfalfa and increase the release of soluble proteins, which increases the chances of bloat.  After doing some research, I decided to stay the course, since I had already been grazing the field for 2 weeks and the cows rumen was adjusted and it was only a 50% mix.  I didn't have any issues with bloat, but you would not have wanted to stand too close behind them.  Their manure pats had gone from a perfect pie to something you could suck up through a straw! The runny manure also had a fowl smell to it. The cattle, standing in knee high forage would beller at me as I drove by, so I gave them a couple of small square grass bales to settle their stomachs, which they gobbled up. 

In conclusion, I feel as though it is relatively safe to graze a 50% mix of alfalfa and I plan to graze this field in the spring before it goes to bloom.  Which is something that I have not done yet.  I will provide an update when that times comes.