Topics : Forage Quality & Testing : Putting Forage Quality in Perspective
Putting Forage Quality in Perspective
Additional Forage Quality Information via the Forage Information System (FIS)
Significance of Factors that Influence Forage Quality
All of the ranked factors above can be controlled to some extent through proper management. For example, maturity can be controlled by adjusting harvest dates. The highest quality species that fit the available soil resources should be chosen. Drying agents and preservations may help to avoid rain-damaged forage. Soil testing can identify optimum lime and fertilizer additions. Although variety selection is very important for yield and persistence, it is of relatively less value to forage quality.
Attempts being made to modify alfalfa plant composition and leaf-to-stem ratio through breeding, as with the multileaf alfalfas, using chemical analyses as the selection criteria. Several alfalfa trials throughout the United States now include forage quality in their evaluation of new varieties. At a given trial site, all varieties are harvested on the same date and then evaluated for forage quality. Any differences in maturity among varieties could influence the ranking of those varieties. In other words, some of the reported differences in forage quality between varieties may only be reflecting that they were harvested and compared at different maturities. Keep in mind that maturity is the most important factor influencing forage quality.
Selection for forage quality in corn silage is now being done, and it is likely that many commercial companies will be promoting hybrids on this basis as well. Preliminary studies at Cornell University, Michigan State University, and the University of Idaho indicate that there is a range in overall silage quality among hybrids. It may be possible to breed for higher stover quality while maintaining a high grain-stover ratio, and develop a silage hybrid with overall higher digestibility. As with alfalfa, selection may be based on chemical in vitro analyses, with little or no actual animal performance data to back up forage quality claims. This means that varieties ultimately will be compared for animal performance on the farm by the forage producer. Claims of improved forage quality may be added only after those varieties excel in animal performance tests.
Keeping quality in perspective If you want to produce high quality forage, keep in mind the ranking of quality factors and their relative contribution to quality. While all six factors described are important, using high quality varieties will be advantageous only when the other five factors are operant. Quantity (yield) of forage is also a major consideration. Evaluate your total forage requirements, and then select the crop and the appropriate acreage of that crop that best meet the needs of the group or groups of animals to be fed. It ultimately comes down to economics; high quality forage can help keep farmers in the dairy business.