When determining if your native pasture is worth haying, first you need to determine what species are currently established. Typically, native pastures consisting mainly of big bluestem, eastern gamma grass, Indian grass and little bluestem are going to be the predominate species best suited for hay production. Native pastures in western Oklahoma will mostly contain mostly short and mid-grass native ranges.
Annual haying is a common practice, but alternating haying and light grazing every other year can be beneficial. Early July is the optimum time of year to be haying native grass pastures for hay. There are some basic production practices to maximize production potential of these hay meadows. Since native hay meadows are a long-term investment, they should be managed in such a way to sustain long-term productivity.
The most important management practice is cutting date. In most years, the optimum cutting date will be between July 1 and 10. Harvesting native hay at this time will achieve a good balance of forage yield and forage quality while also allowing the native stand to recover the rest of the year to sustain production for following years.
The main key to managing any perennial hay field is to maintain a balance between forage yield and forage quality. Time of cutting will be the primary production practice that will determine the forage yield and quality. The maximum forage yield and maximum forage quality hardly ever occur at the same time. Hay tonnage typically will peak in late-August, while crude protein and digestibility are usually highest in May.
The second most important management practice is proper cutting height. Cutting height can easily be overlooked, but can be highly detrimental to the life of the stand. Native grasslands should never be cut shorter than 4 inches. Growing points on these grasses are elevated during this time of year. If the growing point is cut off, then production will be greatly reduced the following year.
Cutting height also is important because most of the native grass species need time to re-grow to build root carbohydrate reserves. To sustain a native hay meadow it is recommended to only harvest it for hay once a year. Native grass species grow rapidly through May and June, but will exhibit slow re-growth in July after harvesting a hay crop. In addition to the slow growth, the re-growth often is less palatable as well. Native species have adapted through natural selection for these traits to ensure grazing animals will not exhaust the root carbohydrates prior to winter dormancy.
Field research conducted by Oklahoma State University has shown that forage tonnage can be increased with an application of fertilizer; however, it is rarely economical to do so. When adequate moisture is available during spring and early summer, 30-80 pounds of actual nitrogen fertilizer can increase hay yield and crude protein. Herbicide applications are rarely warranted on native grasslands. If managed properly, there should be a mix of native forbs and legumes that benefit the grass production.
Some small plot studies conducted by OSU has shown an increase in grass production is possible when broadleaf weeds (forbs) are controlled with an herbicide application. However, increases varied depending on growing conditions and thickness of grass stand. Previous mismanagement of the pasture often leads to more weeds.
Herbicides such as 2,4-D and/or dicamba are effective when applications are made to small weeds. As weeds get bigger, more costly herbicides are often needed.
Good management practices include harvesting prior to mid-July, leave at least 4 inches of stubble, harvest only once during the growing season and manage the re-grown forage in the dormant season with either fire or grazing.
For more information about harvesting native grasslands for hay, contact your local Oklahoma State University Cooperative Extension Office. Information also can be found from the OSU factsheet “NREM-2891 Native Hay Meadow Management.”
Bushong is Oklahoma Cooperative Extension Service northwest area agronomy specialist.