Turnip Forage Potential Under Rated

REGINA - Feb 23/04 - SNS -- Trials growing and using turnips as a forage have over-turned previous recommendations in western Canada and Saskatchewan Agriculture and Food is now saying producer should consider this old world crop.

"Brassica species such as turnips, rutabagas, rape, kale and Swedes have long been used as winter-grazing crops in much of the world. Rutabagas and turnips, for example, provide roots, stem and leaf growth for grazing and have good tolerance to frost," says Sherrilyn Phelps, a soils and crops agrologist with Saskatchewan Agriculture, Food and Rural Revitalization in North Battleford.

She says a 2002 study of turnips at the Scott Agri-Arm site yielded tops with 20 per cent protein, and roots of 12 to 15 per cent protein. This compared very favourably with good alfalfa grass hay, which has a protein content of about 16 per cent. The digestibility of the turnips was also high, with total digestible nutrients of 75 to 90 per cent and relative feed value of 350 to 400 per cent. Phelps says these nutritive components, coupled with the proven adaptability of other brassicas such as canola and mustard, suggest that turnip as a forage crop may have a fit in the province's forage and livestock industry.

But, while turnips appeal to livestock producers for the aforementioned reasons, more information is needed for their use in Saskatchewan. The objective of last year's study, therefore, was to establish a growth curve for turnips: "Although we know that canola grows well here, we wanted to know when the plant produces a tuber, for example, and when the maximum production period is expected. In short, we wanted to know when it should be grazed, and what forage yields can be expected," explains Phelps.

Trials were conducted at Scott, Loon Lake and Lashburn, with the conventional turnip variety Marko being compared to a hybrid variety, Typhon, which is based on a cross between turnip and Chinese cabbage and so has less tuber and more above-ground production. The canola hybrid LL2663 was also included in the trial.

When, at the end of the trial, the total biomass was analyzed, all the brassicas showed similar dry matter accumulation. Other information was more surprising.

"For example, it was recommended that grazing take place 60 days after seeding, but our results indicated that this timing may be too late. I think we are grazing one to two weeks too late. We always thought that turnips would offer fall grazing, but now we think it may be best used as a summer-pasture relief."

Because of the dry year and the infestation of grasshoppers and flea beetles, there was little regrowth in any of the plots, so Phelps says they still don't know the potential of re-growth production. This reason, among several others, is why she is hoping the trials can be carried out again this year.

The 2003 study was carried out with funding from the Western Applied Research Corporation, a north-west Saskatchewan producer group that conducts its trials at the Scott Agri-Arm site.

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