Manage Forage for Increased Yields

REGINA - Mar 8/04 - SNS -- There is a greater need to boost forage yields this year in Canada to account for the larger number of cattle on feed on farms in the country, says Todd Jorgenson, a rangeland and forage agrologist with Saskatchewan Agriculture, Food and Rural Revitalization in Yorkton.

As a result, growers need to consider ways to increase their forage supply, both pasture and hay. Seeding of annual and perennial forages will be the most common option, and it should not be undertaken lightly. Many factors besides yield and longevity must be considered.

"Even market conditions can play a part in the choice of forage to be seeded," he says. "Because of the current BSE situation, for example, there are more animals on farms right now so it may be more practical to use annuals for additional greenfeed or pasture. Annuals can provide emergency forage, while perennials, although less expensive in the long run, typically will not provide much forage in the establishment year.

"On the other hand, the price of perennial forage seed is currently quite low, so perennials may be a wiser move in the long term. If perennials are being considered, however, there are a few other things to consider," says Jorgenson.

For example, he says, soil type and climate must be assessed.

"Neither the price nor the intended use of the forage are important if the forage won't grow on the land. So first you have to look at what your land is capable of, then select a forage species that is best suited for your land base and the intended use."

Soil considerations include pH, salinity, waterlogging, drought and overall productivity. For example, Jorgenson says, soils with low pH can reduce nitrogen fixation in legume crops, so grasses may be preferred. Tall wheatgrass, for instance, has a strong tolerance for saline soils, spring flooding and waterlogging. Crested wheatgrass, on the other hand, is extremely long-lived, drought tolerant and well adapted to sandy soils, but it can't tolerate flooding.

"To narrow down the selection, you really have to look at the combination of soil and climate factors."

The next consideration is the end use of the forage. A basic question refers to whether the forage will be used for pasture or hayland.

An illustration of how usage impacts forage choice is bromegrass: meadow bromegrass is easier to manage as a pasture grass than smooth bromegrass because of its rapid re-growth after grazing, but smooth bromegrass is more productive and easier to harvest as a hay crop than meadow bromegrass.

The end use can also influence the choice of variety. A dairy farmer in an irrigation or high-moisture area, for example, may choose an alfalfa crop that can yield three cuts a year, and will sacrifice stand longevity for rapid re-growth and high yields.

Seeding complex mixtures of grasses, or grasses and legumes has been a practice in Saskatchewan, but it is now being questioned. Jorgenson says mixtures typically do not perform well in pasture situations, partly because of the varied palatability of the different species. Livestock will graze the more palatable species, which will eventually result in dominance of the least-palatable species. He also says a single species or a mixture of only one or two species is easier to manage in terms of fertilizer, weed control and harvest, whether by machine or livestock.

"It's better to fence the pasture into different paddocks, seed each with a different species or simple mixture, and use grazing management to utilize forages based on their growth patterns. Complex mixes are not only harder to manage than single species because of selective grazing, but also because the different growth habits make it difficult for producers to take advantage of each.

"Mixtures also have different growth compatibilities. Many creeping rooted forages, for example, have greater survivability than a bunchgrass with quick re-growth, and it will push the bunchgrass out of the stand. Weed control with herbicides can also be more difficult with mixtures if the stand contains both grasses and broadleaf legumes," says Jorgenson.

Mixtures can be justified on variable landscape areas such as knob and kettle, however. Because of the rolling landscape, seeding separate species is impractical, while seeding a mixture allows forages to become dominant on the sites to which they are best adapted. Crested wheatgrass, for example, might become prominent on the drier hill tops, while timothy or meadow foxtail might thrive in low spots that are prone to flooding.

"After considering all the factors, producers can then consider the specific forage species and their yields. Many new varieties of grass and alfalfa are also introduced every year. Comparative yield values are available through seed companies and also in the SAFRR publication 2004 Saskatchewan Forage Crop Production Guide. The latter is a useful reference for all aspects of forage crop management, and is available at SAFRR's rural service centres and on the SAFRR Web site at www.agr.gov.sk.ca," says Jorgenson.

The subscriber version of the article is available by Clicking here