We got in a truck-load of straw this week. “Hay” is cut green, and may be alfalfa, grass, or grain. “Straw” is the mature (yellow) grain-stalks, after the grain-heads have been cut off by the combine.
While hay may have protein up to 20% and Total Digestible Nutrients of 50% and more, straw is not nearly as good a feed – when the weather is good. But when the temperature drops below zero that straw becomes a wonderful source of energy!
Cattle in Montana range out year-around – that means 100o above , or 30o below. At temperatures below freezing, the cattle depend on the heat of digestion to keep themselves warm – and that’s where straw comes in.
In early pregnancy a cow may only need 7% protein to maintain body weight with a small fetus developing inside her. The native grasses – even after they have gone dormant – provide enough protein and energy while the weather is moderate. As long as the grass is available through the snow, it will meet the cow’s maintenance requirements. But it takes a lot more feed to keep her warm when the temperature drops. Eating straw supplies that additional energy at about half the price of hay.
In the winter, the ground is frozen in Montana. When a cow lies down, that frozen ground pulls out a lot more energy. But if she is lying on straw, her energy requirements are 30% less. So I like to give the cows all they can eat when it is cold, plus enough to bed on.
This straw came by semi-truck, with a 40-foot semi-trailer and a 36-foot “pup” trailer – 76 feet in all. It was in “mid-size” square bales of 3’x3’x8’, weighing 600 pounds apiece - 84 of them.
With this load of straw in the stackyard I can finally relax, knowing that I have enough feed for my cows – no matter when winter sets in and how long it lasts.