Pasture and Forage Minute: Double Cropping Forages, Alfalfa Dormancy
Double Cropping Forages on Crop Ground
There are many producers looking at ways to grow more forage for hay or pasture. Double cropping annual forages can be an option.
Successful double cropping of annual forages requires good planning and timely operations along with some timely moisture. To use this approach this spring, small grains like oats or spring triticale, would need to be planted here in late March to early April. Grazing of these plantings can begin around the third week of May and last until early July if stocked and managed properly.
As portions of this spring planting get grazed out, the double crop of a summer annual grass like sudangrass or pearl millet can be planted. With adequate moisture, the summer annual grass will be ready to graze in 45 to 50 days and may last through September.
This double crop forage strategy works even better if winter annual cereals like winter rye, wheat or triticale were planted last fall for spring forage. They will be ready to graze earlier than any spring planting and like the spring plantings, as portions are grazed out, plant summer annual grasses to begin grazing them by mid-summer.
Another strategy is to plant the summer annual grasses first in mid- to late May. Graze portions of them out in August, then plant oats or turnips or both for late fall and winter grazing.
Of course, adequate moisture or irrigation is needed for these options to produce both double crops. Thus, it is wise to have a nearby pasture where animals can be placed and fed temporarily if extra time is needed to grow sufficient forage for grazing.
Fall Dormancy in Alfalfa
The time for spring planting alfalfa is just around the corner and two traits often confused are fall dormancy and winter survival. Let’s look at fall dormancy today.
Fall dormancy is a measure of an alfalfa plant’s ability to regrow in the fall after harvest and spring following winter. It is scored on a scale ranging from one to 11, with one being most dormant and 11 the least. Higher dormancy means a harvested plant will focus its resources in the fall on building reserves to survive the winter and less on new growth.
This tendency toward slower regrowth manifests throughout the year, with less dormant varieties typically recovering faster in the spring and producing overall higher yields. Another role dormancy plays is keeping plants from starting growth during the random warm-ups in the fall and winter months. Plants that break bud during these periods are subject to winterkill.
Finally, fall dormancy can impact the harvest timetable. Lower dormancy rated alfalfa plants will regrow slower after harvest as well. This translates into more time to remove forage from the field before “windrow disease” and field traffic become a concern.
In the past, fall dormancy traits were linked with winter survival. With new varieties, this isn’t always the case, so fall dormancy needs to be evaluated on its own.
Variety selection depends upon your management, production goals and ability for a stand to make it through winter without sacrificing additional yield. If you have regular issues with stand winterkill, a lower rated variety with improved dormancy. In Nebraska, we recommend dormancy ratings one through five.