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While American tobacco growers have watched the demand for flue-cured and burley crops slip over the last few years (production rates are still at 86 percent of 2004 totals), the one segment of the industry that has continued to creep upward is dark tobacco—both its fire-cured and air-cured varieties. Because of the increasing demand, the dark crop has become somewhat of an intriguing topic with growers looking to diversify their operation, but the problem is less about growing it than it is about curing it.

“Dark tobacco is still more of an art than it is a science,” says Dr. Andy Bailey, associate extension professor and dark tobacco specialist with the University of Kentucky/Tennessee. “Dark tobacco can be grown in a lot of different places, but as far as the fire-curing process, what’s holding people back is not having the experience that that we’ve been passing down between generations for 200 years. We can tell people in North Carolina how to handle dark air-cured, but fire-curing is a different story.”

About 90 percent of dark tobacco goes to the manufacture of domestic moist snuff, which helps explain its growing popularity as the public is being pushed away from cigarette smoking and is thus seeking alternatives. Both fire-cured dark tobacco and air-cured dark tobacco are traditionally grown in the pocket that includes 25 counties in southwestern Kentucky and nine counties in northwestern Tennessee. A slightly different variation of fire-cured is also grown in 13 counties in southern Virginia.

While other nontraditional regions could almost certainly produce dark air-cured, the problem is that contracts for air-cured varieties only account for about 33 percent of an already limited market. So without a feel for fire-curing, it would be that much more difficult to break into this niche sector.

“We have the proper climate and probably some of the better soils you’ll find for growing tobacco in Kentucky and Tennessee,” Bailey says. “But what brought the crop to this area was that at one time we had a huge supply of hardwood trees that supplied the slabs and sawdust needed to fire cure. As a result, the manufacturers that use dark tobacco, such as U.S. Smokeless Tobacco and Conwood Company, migrated to the area and they had no reason to go elsewhere for the tobacco they needed. So the whole operation has remained pretty centrally located ever since.

“Our growers are only restricted by the demands of contracts, so we’re going to grow all the dark tobacco that the manufacturers will let us. And traditionally we’ve had no trouble meeting their needs. So even if you’re in the area and have been growing burley tobacco for a long time, it’s not easy to obtain a contract for dark tobacco—especially dark fire-cured tobacco. Having that contract is kind of like a badge of honor.” 

The demand for dark tobacco had been inching upward for almost two decades but experienced a huge jump in 2008, going from 55.2 million pounds of production in 2007 to 87.5 million pounds last year, catching the attention of tobacco growers outside of the traditional areas. Experts agree that manufacturers overestimated the 2008 market, though, leading to a surplus of product and significant contract cuts for 2009. However, this year’s estimates still remain at a robust 22,650 acres planted, yielding 71.4 million pounds for a value of $171.3 million (down 18 percent from 2008 but still up 35 percent from 2007).

Now the question is what will happen going forward? This year’s surplus will likely cause some carryover for 2010, but, in all, market conditions still seem favorable. As a result, nontraditional dark areas are taking a closer look at the crop.

Heading east
With the hopes that there could be another surge in the market, combined with the fact that North Carolina-based giant R.J. Reynolds (sister to Conwood Company under the Reynolds American umbrella) reportedly offered between 15 and 20 small local contracts for dark tobacco this year, experts in the Tar Heel state are researching the feasibility of making dark air-cured tobacco a more significant part of the state’s repertoire.

“The consumption of smokeless tobacco is the only area that is increasing in sales in the U.S.,” says Dr. Loren Fisher, a tobacco specialist with the North Carolina State University extension program. “Last year there was a huge demand for dark tobacco in Kentucky and Tennessee, but I think they over-seeded this year for what they’ll need. So contracts are down now, and it’s hard to measure exactly where the market will be. But we’re gathering information and getting prepared in case the manufacturers decide they want us to grow it in the future.

“We grew air-cured dark tobacco at several research stations last year and it graded very well and was well received by the company that evaluated it. This year’s crop seems to be good as well. It looks to be usable; it’s good quality and provides a good yield. So it looks like North Carolina can produce what the companies want.”

The NCSU researchers successfully grew five different varieties (Narrowleaf Madole, KY 171, VA 359, PD 7312 and KT D8) in the state, ranging in locations from the mountains in the west to the eastern coastal plains. Experimenting with the nitrogen rates (200, 250 and 300 pounds per acre), the research stations all produced between 2,300 and 3,300 pounds of dark tobacco per acre.

“The dark tobacco certainly yields much higher than burley on average,” Fisher says. “We topped it at 16 leaves which is the way it’s typically done, and even though there are fewer leaves, you can see that they are going to weigh quite a bit. And last year we received $2.28 per pound for our dark air-cured, which is well above flue-cured and burley prices.”

Size up
Dark tobacco generally looks like a darker green version of flue-cured; however, in most ways it is more comparable to burley—although there are many differences. Production practices between dark and burley are similar in that both are set between mid-May and mid-June and harvested between mid-August and mid-September. Both soils should have pH in the 6.4 to 6.6 range, and nitrogen rates should be the same. The insects, weeds and diseases are also similar, as are the pesticides used.

Besides the fact that dark plants are more prostrate than burley and have thicker, darker leaves, the differences begin with dark tobacco needing more space. While burley plants are generally set 61 cm apart in-row, it is recommended that dark be spaced between 71 cm and 86 cm apart, and with between 97 cm and 112 cm row spacing. They are also going to be topped differently. Whereas burley is topped between 18 and 22 leaves, dark is topped lower, between 14 and 16 leaves. This helps create the large, wide-tipped leaves the variety is recognized for. Because of a lack of disease-resistant varieties, rotation is also more of an issue with dark crops and should ideally be planted in at least a three-year rotation with grassy crops.

Dark tobacco is best topped at the elongated button stage. Basal sucker growth is more prevalent in dark tobacco, and its thicker leaves are more susceptible to damage from sucker control materials. The standard practice is to apply contact fatty alcohol material at topping (alone or with local systemic) and contact and a local systemic seven days later.

Dark tobacco should not be left in the field after it has ripened. It will not turn yellow like burley; instead its leaves will become thick, brittle and oily and will crack readily when pinched. Dark tobacco is stalk cut like burley, and that’s really where the art of producing this crop begins.

“There are a lot of harvest logistics involved with dark tobacco,” Bailey says. “You can’t just fly into a field and harvest the whole thing at once like with burley. It has to be a pretty systematic process because the plant structure is so different, and it’s a lot more sensitive to sun damage, so you have to take a lot of steps to protect that leaf once it’s cut and get it under some protection.”

Dark tobacco cannot be impaled on sticks immediately after cutting as it must be field wilted to reduce breakage. It can remain in the sun briefly with its cut stalks facing the sun, but needs to be moved into the shade within 30 to 45 minutes.

“These leaves are a lot more brittle than burley and they’ll break on you,” says Dr. Layten Davis, an internationally recognized tobacco expert who retired from academia after 20 years and is now a principle scientist at R.J. Reynolds. “When I say field wilt, I’m talking about a matter of a few minutes. Don’t try to cut it and spear it in one motion because you’ll break the leaves off it. You need to cut it, lay it down carefully and let it briefly wilt.

“A good way to do it is if you cut it late in the afternoon and lay it down, because it can still sunburn on a cloudy day. And you have to be really careful about the sunburn.”
 Cut dark tobacco is particularly susceptible to sunscald. Unlike burley, where sunscald will bleach out with more, less intense sun, dark tobacco will only get worse and blacken. A “field wilt” could take anywhere from 30 minutes under sunny conditions to five hours if there’s no sun before the tobacco can go on a stick. After dark tobacco is impaled, it will generally sit in the shade for a day or two to further wilt before it goes into the barn.

Of all types of tobaccos, air movement is most critical to dark air-cured, which needs to have 12 inches between the sticks when hung, as opposed to burley where you can get by with 6 inches between. Having good ventilation is particularly important in the first three or four weeks of curing to avoid mold problems, with growers keeping the barn doors and vents open except to combat inclement weather. As with burley, weather plays an important part in the cure.

Air-cured dark tobacco requires a slow chemical reaction to take the tobacco from its green color to a uniform brown, and will generally take a week longer to cure than burley, hanging for six or seven weeks. The optimum conditions for this cure will range from 65 degrees to 90 degrees each day, with relative humidity ranging from 65 to 70 percent.

Discovering fire
Once fire-cured dark tobacco is impaled on sticks and set in the barn, it will sit for about five days before the first fire is lit, waiting for a yellow cast to start to come through the leaf. There should be at least 9 inches between the sticks for fire-curing, and increasing that gap to 12 inches only helps the process. With all the barn vents closed except for those at the very top, the first fire will be lit on the hardwood slab, generating low heat (95 to 100 degrees) and high relative humidity (85 to 90 percent) as the brown color gradually comes through in about a week’s time. Traditionally sawdust is used to fuel the fires; however, studies show that woodchips can increase efficiency up to 50 percent—although sawdust will still be needed to dry the stems. A dark crop could undergo anywhere from two to six firings, with each firing lasting between three days and two weeks.

“Every barn fires a little differently,” says Bailey. “It’s not a total control type of thing like you have with a flue-cured barn where you can set the humidity and temperature. It’s sawdust and slabs where you’re building a manual fire under the tobacco, and it’s dependant on the crop itself as far as the size and the amount of moisture present. All that determines when you’ll start the firing process and how you’re going to deal with that fire.

“There certainly are basic steps to follow, but the biggest thing is knowing what to do and when to do it, and that just comes from having a feel for the tobacco. That’s why I say dealing with dark fire-cured tobacco is really more art than science.”

Once the color comes through, the next week will see fires taking the temperature to 130 to 135 degrees to dry the tobacco and the midriff down. All the vents will be open to increase ventilation and the relative humidity will be decreased to 75 to 80 percent.

In the final stage, or the finishing stage, there will be sequential, low-temperature, smoldering fires to return a little moisture back into the tobacco and maximize the amount of smoke in the barn.

In all, the entire cure will take six or seven weeks; however, many dark growers “double crop,” where one crop is transplanted in early May and the second about five weeks later. This requires that the two crops be treated completely differently, including pest controls, irrigation and fertilization, but it also requires the first crop be completely cured and out of the barns when the second crop is ready to go.

“When we’re trying to push both crops through one barn we want to have that first one out in five weeks so you’re not cutting that second crop in late September or early October,” says Bailey. “There are some obvious quality issues you’ll notice when you’re trying to push a barn out in four and half or five weeks, like the coloring, but the biggest thing you’ll find are the TSNAs [tobacco-specific nitrosamines]. We tend to see more in barns we really push compared to those that are slower cured.”

As with flue-cured tobacco, direct heat and higher temperatures cause an increase in TSNAs, which is why Bailey says researchers are researching different firing methods.

“We’re looking at some indirect firing techniques and seeing if we can fire less and still produce a similar product for the buyer,” Bailey says. “If someone is firing four or five times, we’re seeing if he can cut it back to three and still produce an acceptable product. We also believe stick spacing plays a key role, so we’re trying to get more air space between sticks to reduce TSNAs, as well as reduce the nitrogen used in the fields. And this year, we’re researching to see if we can begin firing sooner than five days after housing. By starting the fires earlier, we believe we can reduce TSNAs a little.”

Final product
Once cured, dark tobacco is flaked and packed for delivery. The traditional method is to deliver a 400- to 500-pound “basket,” where the tobacco is flaked and arranged in a circular fashion on a hogshead. Between the stripping floor and the finished basket, however, the flakes are stored in bales. About half the contracts this year, though, will be delivered in 200- to 250-pound boxes (or some larger boxes that weigh 700 pounds). The boxed tobacco is still flaked and oriented so the tails and stems are going in the same direction; however, boxes are preferable to growers over baskets because doing so eliminates the intermediate step of storing the flakes in a bale.

The packaging is finished with plastic wrap to protect the tobacco until it reaches its final destination, concluding another cycle of a proud tradition and hopefully yielding a well-deserved high return on investment—a return that many outside the traditional dark areas would like to also cash in on.