Dry beans could reduce yields

Farmers are advised to check quality of bin-run beans before filling the planter

BY TOM BUTTON

With rock-bottom commodity prices, the soybeans in your on-farm bin seem hardly worth the effort of trucking to the elevator. So why not use some for seed?

Check the quality first, seed experts warn. In many parts of Ontario, the 1998 seed crop is suffering the highest levels of splits and cracks since 1991.

Even if you get good scores from a seed lab, don't be too confident. With a crop that's come out of the field at so low a moisture content, any physical handling can multiply the number of damaged seeds.

"You can start with a germ test of 90 per cent and think everything's okay," explains Gary Lannin of First Line Seeds. "By the time you put some of these crops through a couple of augers, you may be down to 60 per cent."

Quality is worst in Huron, Perth and other pockets hit with severe drought last year, reports Albert Tenuta, OMAFRA soybean specialist. Moisture-stressed crops produced mediocre quality seed to start with. Harvesting at low moisture contents hurt quality even more.

Seed quality in the extreme southwest is generally excellent, largely because of adequate moisture through the growing season. But growers who opted to harvest when moisture sank below about 14 per cent should take a hard look at their seed quality.

Seed labs are reporting high levels of abnormals this year - seeds that sprout, but have a shriveled cotyledon, a twisted stem or other deformity; and almost always, the culprit is low moisture content at harvest.

Will those seeds produce viable plants in the field? "A lot depends on the spring," says Don McClure, soybean breeder for Novartis. "If it's a perfect spring, you might get viable plants....If it's a backward spring, the grower could be very disappointed."

McClure says Novartis, like other seed companies, is rejecting many seed lots. "This is the worst that we've seen from some areas since 1991."

Across the province, germination may also have been hurt by last year's weather patterns. Crops seemed to mature overnight. McClure recalls that as usual his team monitored its varieties through September to track their progress toward maturity. Mid-month, the job proved impossible. Every variety seemed to race to the finish, with virtually no difference in maturity date at McClure's London plots. Many varieties, whether they were 2800 or 3000 heat unit lines, finished at the same time.

Soybeans are well known for being able to compensate for poor stands by branching out and filling in gaps. But growers shouldn't bank on getting an even crop out of uneven seed, says Tenuta. If the dud seed were perfectly distributed through the hopper it might be okay, he says. But too often the poor seed will be planted in patches, leaving holes too big for the neighbouring plants to fill in.

McClure says growers should take this year's seed quality concerns as a word to the wise, even if they're confident of their own seed supply. "We should be handling soybeans like glass," McClure says. "Don't drop or throw the bags. Be as gentle as you can."

© copyright 1999 Agricultural Publishing Company Limited.


back

Winter wheat's N window

Not rushing for an early application is one way to preserve soil nitrogen

BY TOM BUTTON

Hindsight's easier than foresight in picking the best time to apply nitrogen to your winter wheat. In a perfect world, that last frosty morning before the three weeks of rain would be ideal.

But in the real world, choosing when to go depends more on how you weigh risk than on simple agronomics. Do you take advantage of frozen soil in late winter - and lose a chunk of your N before crop roots can take it up? Or do you gamble that there will be times in April when the soil is either frozen or dry enough to support the weight of the spreader?

"Don't rush it," recommends Peter Johnson, London-based OMAFRA crops specialist. The more growers learn about how nitrogen disappears from the soil, the more they'll want to wait at least a couple of weeks before spreading, he believes.

Urea's performance is disappointing when it's allowed to lie on top of a moist soil, says Keith Reid, OMAFRA fertility specialist at Walkerton. Under those conditions, the urea changes into a gas in a process called denitrification (also called volatilization).

Temperature is critical, Reid adds. In Ontario winter wheat fields through late March, with average temperatures closer to 5C, losses will more likely be in the three- to six-per cent range. Later, at 15C, losses may be 12 to 20 per cent.

Negative reports about urea come mainly from the U.S. Corn Belt, where urea is surface applied to no-till fields in early May. Tests show that with the mercury at 25C, growers can lose between 25 and 50 per cent of the urea nitrogen.

Loss rates, however, depend on more than temperature. If urea is applied late March, losses may be zero if the application is followed by a couple of inches of snow. When the snow melts, it will slowly dissolve the urea pellets and wash the nitrogen into the soil. Losses will also be zero if the soil stays frozen and dry for a couple of weeks until there's a gentle half-inch rain to get the N into the soil.

In the worst-case scenario, the surface is wetted by one-tenth-inch rains that dissolve the pellets but don't carry the nitrogen down into the soil.

Reid and Johnson say 28 per cent UAN is as equally effective as urea. A quarter of the N in 28 per cent is in the nitrate form, however. That makes that portion of the N more vulnerable to leaching and denitrification. As well, if the 28 per cent is applied after the crop breaks dormancy, the nitrate can burn the tender new growth.

Higher-priced nitrogen forms, including ammonium sulphate, provide insurance against nitrogen loss. When yields are higher with ammonium sulphate, the sulphur gets only a mere fraction of the credit, Johnson says. Instead, yields can be better, because ammonium sulphate is less affected by urease, an enzyme released by rotting residues that attacks urea.

While 28 per cent and urea can give equal yields most years, 28 per cent may be the better choice if the urea will be applied with a spinner spreader. Johnson doesn't mince words about spinner spreaders. "Half the units never get calibrated," he says. "Even if they are, you can get a build-up on the spinners that totally destroys the pattern, especially on humid days."

In replicated tests on fields in 1998 that had urea applied with spinner spreaders, Johnson's group found yield ranges of 22 bushels per acre between parts of the strip that were under- and over-fertilized.

Reid's experience was even worse. He was called to barley fields where the spinner wasn't rotating, so the urea simply poured out the back of the rig. "It was more than one field, and it was more than one dealer," Reid says. "It makes you wonder."

© copyright 1999 Agricultural Publishing Company Limited.


back

Cereal corn pushes planting frontier

Yields are lower than conventional hybrids, but so are input costs

BY TOM BUTTON

It's called cereal corn, and it's making its debut this spring as the world's newest and earliest commercial corn.

Manitoba-based CanaMaize is launching the new corn with up to 10,000 acres worth of seed, and co-owner David Rourke predicts it's just a start. Cereal corn, he says, has the potential to add huge new tracts to Canada's Corn Belt.

Most of those acres will be in the West or in the Maritimes, however. With yields of 50 to 80 bushels per acre, Rourke says, cereal corn can't compete with conventional hybrids.

Still, for farmers on Manitoulin Island or in parts of the New Liskeard or Rainy River districts, the 2000 heat unit corn may offer a higher per-acre return than barley, and better feed value as well. Needing just 60 days from planting to silking, cereal corn may be the only way for these farmers to grow corn.

Cereal corn is different from conventional corn in just about every way, including the fact that it isn't hybrid. Farmers can save part of their harvest for planting the next year - a practice that disappeared in the Corn Belt nearly 50 years ago.

Cereal corn contains a reduced stature gene, reports Lana Reid, corn breeder for the federal government at Ottawa, which developed the CanaMaize line. The gene makes the corn short. Typical height is about three feet.

Everything else about the plant is also a third to a half smaller than normal, including leaf width. "You'd recognize the kernels as corn," says Lianne Dwyer, Ottawa researcher who has helped develop the agronomic package for growing CanaMaize. Kernels, however, are also about half the size of conventional corn, although they have very good test weight and protein levels.

Cereal corn can be planted through a drill or air seeder, so growers don't need to invest in expensive corn planters. Recommended population is about 40,000 plants per acre in any row width.

Equally important, cereal corn can be harvested with a cereal head. It can even be swathed for later combining or be left in windrows for fall and winter cattle grazing.

Rourke says cereal corn will typically yield 10 to 20 bushels more than barley, and sometimes even more. Corn will also fetch a higher per-bushel price than barley, especially in areas needing swine feed.

Dwyer says cereal corn faces several challenges. Ear height is very low. In fact, in some tests last summer, ears touched the ground at harvest, and the only way Dwyer got her 70 bushels at Ottawa was by going back over the plots and picking up ears that the combine missed.

As well, cereal corn has a flint-type kernel. Flints are harder to dry than conventional dent-type hybrids, Dwyer points out. "With low yields, there isn't a lot of money left over to spend on drying." Corn is also more prone to drought stress during pollination than barley, so yields may be more variable.

Cereal corn doesn't produce bedding. That's another drawback, especially in Ontario where, many growers turn to barley as much for the straw as for the grain, she says.

Still, Dwyer says that Ottawa is working on three new cereal corn varieties. "It's a neat, low-input crop," she says. "With further development, it may have a fit with a lot of farms that wouldn't think of using it now."

© copyright 1999 Agricultural Publishing Company Limited.


back

Corn inoculant could boost yields

It's a long way from commercialization, but researchers report that an experimental inoculant increases N efficiency

A research team has boosted corn yields by up to 20 per cent by spreading an inoculant at planting. The routine makes the crop more efficient at using nitrogen.

Results are preliminary, but the scientists at the Ottawa experimental farm are planning a series of larger trials aimed at eventual field use.

"We're a long way from commercialization," cautions researcher Sherman Nelson. While farmers already know how and when to inoculate their soybeans, inoculation for corn is more complex and will take more study.

Early results show the corn inoculant, made up of three species of soil fungi, could help corn growers get higher yields while applying less fertilizer. In plots at the station fertilized with 100 kgs/ha N (90 lbs N per acre), Nelson got a 20 per cent yield increase when he applied the corn inoculant under the seed, compared to non-inoculated plots.

In fact, the inoculated yield in the 100 kgs/ha plots was equal to the corn yield in non-inoculated plots that had been fertilized with N at 200 kgs/ha (180 lbs per acre).

Results were less dramatic in plots fertilized at lower rates, and also in plots where the nitrogen was supplied via manure, Nelson points out.

Interestingly, inoculated plots had lower infection rates from fusarium, possibly because the inoculant gave the plants a better nutritional and overall health profile, so they were better able to fend off the disease.

A series of tough questions remain, however. Early testing, for instance, shows a wide variation in the way specific hybrids interact with and benefit from the inoculant.

As well, researchers need to work out how to make the inoculant and how to apply it. The inoculant is a mix of three separate soil fungi. That's different from soybean inoculants, which are made from bacteria.

The difference is crucial, because it's relatively simple for labs to culture huge numbers of bacteria that can then be packaged and applied to the soybean seed. It appears the corn inoculant, by contrast, may have to be grown on living corn roots. To date, Nelson has produced the inoculant for his experiments in pots of field soil.

As well, there are questions about how best to apply the inoculant. Early testing has looked at applying the inoculant in-furrow, and also in a clump underneath each seed.

Uncertain, too, is whether growers would lose some or all of the effectiveness of the inoculant if they applied heavy rates of chemical N. - Tom Button

© copyright 1999 Agricultural Publishing Company Limited.


back

Slower planting could save $10 per acre

With a planter speed of 5.5 mph, corn growers can figure on getting the best blend of planter performance and efficiency.

More growers need to cover more acres, however, and there's always the threat that the next cloud will put an end to planting for another week. But how big a gamble is it to nudge the throttle up an extra mph or two?

It turns out the answer is more complicated than the industry used to think. High-speed planting does hurt the grower's bottom line, but in a backhanded way.

"We didn't see any significant impact on yield," says Paul Hermans, eastern Ontario agronomist for Pioneer Hi-Bred, who worked with regional growers last year to set out 11 planter-speed tests. Plots were planted at four, six and eight mph with JD 7000, 7200 and White planters.

Biggest difference was in seed cost. All planters drop-ped more seed when driven at faster speeds, with most of the extras going into doubles and triples, Hermans points out. See Over-planting.

Hermans calculates the extra seed cost at $10.22 per acre. Extensive research, he adds, suggests that doubles and triples don't hurt yields: they simply don't help so the extra seed is a waste. Skips and long gaps, however, do hurt yields.

In other years, with more difficult planting and germination conditions, the faster speeds would likely have created gaps.

Variations in seed depth affect the time to emergence, Hermans says. Delays of 10 to 14 days can cut yields by four to six per cent. Delays of 21 to 24 days cause losses as high as 15 per cent.

In tests with Indiana farmers, Purdue University corn specialist Bob Nielsen has found growers should expect an average two- to five- bushel-per-acre yield loss for every extra mile per hour of planter speed.

Nielsen says growers don't realize how much they're asking from their planters. In 30-inch rows, with a speed of five mph and a 26,600 per acre targeted seeding rate, each planter unit is covering 7.3 feet per second, and dropping 11.2 seeds. With a 32,000 per acre target, each unit is dropping 13.5 per second.

Bump the speed up to seven mph, and each unit must drop 15.7 seeds per second for the 26,600 rate, and an incredible 19 seeds per second at the 32,000 drop rate. Try snapping your fingers that fast.

At those speeds, something as innocent as a chain with a bit of rust can cause jerks that will hurt planter performance across the field, Nielsen says: "Speed kills."

© copyright 1999 Agricultural Publishing Company Limited.


back