Planting winter rye following soybean or corn silage harvest is a good way for dairy producers to increase feed production from limited acres, say University of Wisconsin dairy specialists. Fall-planted rye can supply up to 4 tons/acre of forage for dry cows and heifers, they add.

Double-cropping rye is a viable agronomic practice in most regions in Wisconsin, say the specialists. Research and demonstration data does show, however, that earlier planted rye will produce more tonnage the following spring. If planting is delayed, spring forage yields will be reduced. Spring-harvested ryelage can be fed to heifers and dry cows, and early harvested ryelage often contains 15% protein and is suitable for lactating dairy cows.

Fall-planted rye has several advantages:
● It’s a hedged emergency forage crop if alfalfa winterkills.
● Winter rye will grow later into fall and earlier in spring, so it extends the growing season and thus captures more sunlight and converts that energy into forage energy for livestock.
● It provides dairy operations with a forage for dairy heifers and dry cows that will lower the ration’s TDN. Feeding forages with less energy will help keep those animals from getting too fat.
● For grazing operations, if winter rye is planted early enough, lactating cows and heifers can make one or two rotational grazing passes over the field, extending the grazing season. The following spring, rye can be the first grass grazed and then plowed under for green manure for a subsequent spring-planted crop.
● Manure can be applied before seeding and again just after harvest in May or June.

The crop can be planted anytime after Sept. 1 and as late as early November, depending on weather conditions. A typical seeding rate is 90 lbs/acre; however, some producers may choose to plant up to 120 lbs/acre to try to increase forage yield. Another option is to reduce the rye seeding rate to 70 lbs/acre and interseed alfalfa in spring with a no-till drill. If no manure is applied, 40-60 lbs/acre of topdressed nitrogen is recommended in spring. An application of manure prior to planting will usually supply adequate nitrogen and other nutrients for optimum forage yield.

Delaying harvest next spring will reduce the protein and increase the fiber content of the forage. A rule of thumb is, if the rye is harvested at boot stage, the forage will have a protein content over 15%. As a result, a mixture of 50% ryelage and 50% corn silage would be adequate to meet the protein requirement of bred heifers (13%). If the rye is harvested later, the protein may be as low at 10%. Thus, the diet may require additional legume silage or protein supplement to meet the protein needs of heifers and dry cows. Late-harvested rye is advantageous in feeding situations where forages are required to reduce the energy intake of those animals.

Rye forages may have a high potassium content, which might be a concern in dry cow rations, the Wisconsin experts warn.