Fast-growing fenugreek could be a rescue crop
What smells like maple syrup and could be used as a short-notice replacement crop after an alfalfa stand fails?
Fenugreek shows potential, says a Wisconsin researcher. Although it doesn't yield as well as alfalfa, its forage quality is comparable to it. The rather exotic-sounding annual legume also maintains its quality longer, widening its harvest window.
Fenugreek is known primarily for the culinary and medicinal uses for its seeds, which are ground and used to add a maple-like flavor to Indian and Mediterranean dishes. Its seeds and plants also have long been prescribed as herbal remedies that lower blood sugar and cholesterol. But its potential as a commercial forage in North America has only been considered since 1992, when it was introduced into Canada.
More recently, it made its way to U.S. research plots, including plots at the University of Wisconsin's Marshfield Ag Research Station in 2006 and 2007.
Its strong maple scent makes it easy to identify in the field, says research agronomist Mike Bertram. “You'll smell it even when you just drive by the field,” he says.
The crop also offers some planting-time flexibility, Bertram adds.
“We seeded the crop at 30 lbs/acre consistently, but experimented with different planting dates, from early May to late June, and found the late-June-planted plots tested the best for quality, with crude protein at 19.8%.”
That compares with 14.3% crude protein for the plot planted in early May. Average yields were similar for planting dates, at 1 ton of dry matter/acre. However, the late-June planting yielded 1.4 tons in 2006, and the early May planting yielded 1.3 tons in 2007.
The plants, which typically grow 1-2½' tall, take 105-140 days to reach maturity. “We harvested when the plants were beginning to die down,” Bertram notes. “The lower plant had some pods on while the upper part of the plant was still flowering.
“We noticed very little regrowth, even after the earliest cutting in mid-August,” he adds. “So, at least in our location in central Wisconsin, you can only expect one cutting.”
The annual crop's fertility needs are similar to those of alfalfa.
“Fenugreek fixes nitrogen and should respond to phosphorus and potassium if field levels are low. But our test plots have high to optimum fertility, so no additional fertilizer was applied after planting.”
Weed control is the catch, says Bertram. “There currently is no herbicide labeled for use on fenugreek in the U.S.” One is approved in Canada, but he doubts there is enough interest to get the crop added to product labels in this country.
In the meantime, the crop should be planted only to clean fields. Another option may be to include it as a mix in pastures, but that has not been tested.
Potato leafhoppers had some effect on the test plots in 2007. “It's hard to say how much they impacted yield, but we did an experimental insecticide application on the field and saw a crop response,” says Bertram.
While he did not identify any specific disease problems, he says it could be susceptible to pythium, rhizoctonia, fusarium and Cercospora leaf spot.
Five fenugreek varieties were part of the Wisconsin test plots, but the researcher says that just two are commercially available — Amber, released in 1992, and Tristar, released in 2004. The latter is the first fenugreek forage-type variety, he notes.
“The other three we tested are still experimental varieties, but we didn't see any major differences among the five. Amazingly, forage yields and protein levels were very similar.”
As a feed, fenugreek's benefits may extend beyond its nutrient analysis, says Bertram.
“It contains a steroidal compound that appears to increase growth rate in cattle and also has oxytocin-like activity, which reportedly improves milk letdown,” he says. “So it could offer benefits in a dairy ration.”