Since mid-2008, Trey Koger has noticed a serious uptick of growers interested in conventional soybeans. That interest seems to be due mainly to three things, said the Mississippi Extension soybean specialist, who spoke at the recent Tri-State Soybean Forum in Oak Grove, La.

“First, over the last decade, there has been a steady increase in the price of Roundup Ready seed. Last fall, there was a significant price increase — more than what was experienced in the past. Some prices cited were 30 to 40 percent higher.”

Added to the mix is also the increased cost of glyphosate. In some situations, there is also concern for glyphosate-resistant weeds.

“Those three factors have turned some farmers’ interest back to conventional soybeans.”

What would growing more conventional soybeans mean in the Mid-South? “Well, there are certainly some challenges.”

• Few public soybean varieties to plant on significant acreage.

Currently, there is very little to choose from in terms of conventional varieties. The majority of public varieties Mid-South growers have access to come out of Grover Shannon’s breeding program in Portageville, Mo.

“There are few conventional varieties like Hutcheson that we used to plant before adoption of Roundup Ready varieties that are still available. But the seed availability on those (is) very limited. “The figure I’m citing isn’t exact, but it’s close: if farmers use only public varieties, there’s not enough available to plant more than 0.5 percent of Mississippi’s expected soybean acreage. That isn’t even scratching the surface.

“Someone might say, ‘Use private conventional varieties instead.’ Well, there are essentially two companies — Hornbeck and Progeny — that are still selling and increasing conventional varieties. The varieties they’re selling have been around for a while.”

Hornbeck and Progeny have some very good conventional varieties, said Koger.

“Yield-wise, several of the Hornbeck conventionals compete very well against some of the elite Roundup Ready varieties. That’s great.”

However, if growers planted all the conventional seed available — whether public or private — “there wouldn’t be enough to plant more than 3 percent of Mississippi’s soybean acreage. That surprises a lot of people. The seed just isn’t available and if the conventional seed is spread out over the Mid-South, we’re looking at only 1 percent, or so, for each state — very, very little.”

• Drift and other treatment issues.

Planting conventional soybeans in a Roundup Ready landscape means glyphosate drift would be a huge concern. However, it’s Koger’s opinion that an even bigger concern is someone spraying the wrong field.

If many conventional soybean acres are planted, “I believe we’ll likely see more loss/damage/devastation of conventional soybean fields from misapplied products than we would from drift. Mixing up a conventional soybean field and a Roundup Ready field would be very easy to do. Misapplication would be a constant threat because the conventional crop and Roundup Ready crop look the same.”

That’s why Koger believes, at least short-term, that there are more opportunities to grow conventional soybeans outside the Delta region. “Geographically, it makes more sense. In the Mississippi hills there are more small operations, a lot more ground applications. In those circumstances, there’s much less potential to spray the wrong field, less potential for drift.

“In many hill operations, you are your own neighbor. There are many more trees and smaller fields. That’s why conventional soybeans would do better in the hills than in the wide-open, vast acreage of the Delta.”

To a large degree, Mid-South growers have figured out how to work with Roundup Ready crops around rice. But a chemical applicator can easily differentiate rice from other crops — whether from the air or ground.

“That isn’t true with Roundup Ready and conventional soybeans. You can’t dye the conventional beans a different color. Right now, the only way to tell the difference is to flag the field corners, alert your farm workers and neighbors, and then start praying.”

• Weed “retraining.”

If conventional soybeans make a comeback, growers will have to go back to old-school weed identification.

“When conventional beans were the norm, we often had to come up with a ‘witch’s brew’ to deal with the weeds in the field. The weeds in the field determined what product was applied — X product for this, Z product for that.”

Timeliness in any soybean field is important, “but in conventionals the weeds won’t wait, at all. To a degree, we’ve all gotten complacent — and I’m not immune to that — spraying glyphosate on Roundup Ready beans. You know, ‘The weeds can get a bit larger and we’ll still take them out with a higher rate.’ Or, ‘It isn’t that important to know what weeds are out there, we’ll just kill them with glyphosate.’”

Plant conventional beans and that will end, said Koger. “We’ll be back to scouting, studying the mix of weeds and products. If we don’t, then the weeds — especially things like sicklepod and teaweed — there are no good options once they get some size on them.

“We will also have to be mindful of carryover restrictions for some of the residual herbicides applied to conventional soybean. For the most part, we have really gotten away from having to worry about carryover of herbicides to the next year’s crop because we rely solely on glyphosate. Go back and plant conventional soybean and we will (have to) rely on residual herbicides to a certain degree. So we will have to be mindful of carryover restrictions for some of these residual herbicides when thinking about what we plant next year.” It wouldn’t be all downside for farmers reverting to conventional soybeans. Among the benefits:

• Money saved.

“We’ve run some economic numbers. Weed control program estimates show that, essentially, the cost for conventional versus Roundup Ready is a wash. Higher glyphosate prices have a lot to do with that.”

Where money is saved with growing conventionals is in seed costs.

“Seed costs are about half that of Roundup Ready varieties. That could add up to $20 to $25 per acre.

“Where there’s an issue, of course, is if the grower doesn’t do a good job managing weeds. If that happens, he’ll have to use more expensive products at higher rates to gain control. If weeds aren’t controlled properly, the $25-per-acre savings could be easily consumed.”

• Early-planted crop

In Mississippi, growers plant the earliest soybean crop in the country. Much of that crop is on narrow rows. By planting in early April on narrow rows, the crop doesn’t typically have to deal with a lot of weed pressure until late April or early May.

“Our early-April crop is usually far along before weed pressure develops. That’s a big benefit for Mississippi growers. A lot of times, growers can also get by with one in-season herbicide application. That would also hold true for conventional beans.”

Several things should be kept in mind about planting conventional soybean, said Koger. “Plant them in fields that are relatively clean of extensive weed pressure. Don’t plant them in fields that have had a lot of weed pressure in recent years. Don’t plant them in fields (with) a lot of sicklepod and morningglories. We can deal with many of the other weeds. However, planting conventional soybean in fields having a lot of sicklepod and morningglories can end up a disaster and get really expensive just to try and manage the weed pressure. “Plant conventional soybean in narrow rows and plant them early to avoid some weed pressure. Finally, plant them where you can isolate the field the best you can from Roundup Ready soybean fields.”

e-mail: dbennett@farmpress.com