When Southern corn growers began putting their combines in the field last summer — some for the first time in years, if ever — they quickly realized this wasn't their father's or their grandfather's corn crop.

Instead of 140 to 150 bushels, producers found themselves harvesting 240 to 250 bushels per acre. Dryland corn yields weren't that high but were high enough USDA has been forecasting record yield averages of 155 to 160 bushels per acre in some states.

Recognizing the impetus for higher production both in the traditional Corn Belt and across the Sunbelt, John Deere has introduced a new line of “bullet rotor” STS (single tyne separation) combines and its first new corn header in nearly 30 years.

The new 70 Series combines — the 9570 STS, 9670 STS, 9770 STS and 9870 STS — will replace Deere's 60 Series combines, according to representatives who spoke at a series of field demonstrations held in conjunction with the company's 2007 product introduction in Cincinnati.

“Farmers have grown their crops for five or six months, and they have one opportunity over 10 to 30 days to harvest them,” said Grant Tice, division marketing manager, John Deere Harvester Works. “Harvest becomes a very critical time.”

The new combines, which are powered with engines ranging from 265 to 440 horsepower, are also aimed at helping farmers cover more ground.

“Large producers are always looking for more productivity, and these new machines cover more acres in less time, deliver ultimate performance during harvest, and offer additional residue-management choices to the producer,” says Seth Crawford, marketing manager, John Deere Harvester works.

Whether configured for Deere's new 600C Series corn heads or with platforms for harvesting rice, soybeans or wheat, the new 9870 STS combine features 15 percent more cleaning capacity to help growers handle the increased residues from higher yielding crops, says Tice.

They also are equipped with larger grain tanks, beginning with a 250-bushel tank on the 9570 STS and running up to 300 bushels on the 9770 STS and 9870 STS models.

The 70 Series combines are powered by John Deere PowerTech Plus engines that are cleaner-burning, more fuel-efficient and factory-approved to use up to a B5 biodiesel fuel blend.

“On our largest combine, the 9870 STS, we offer an industry exclusive Intelligent Power Management system,” says Crawford. “The horsepower on this combine is automatically increased to 480 hp when matched with the new 612C StalkMaster Chopping Corn Head.

“This system was designed to ensure that operators do not compromise productivity when chopping corn stalks during harvest. Customers with the 9870 STS and 612C StalkMaster package can maintain ground speed while chopping and sizing corn residue at the corn head.”

To complement the increased capacity of the 9870 STS Combine and the 612C StalkMaster, Deere is offering a new CommandTouch Multi-Speed Feederhouse drive. This five-speed drive system delivers 45 percent more feederhouse-drive capacity to allow more productivity from the new 600C Corn Heads.

The 9870 STS Combine's DynaFlo II cleaning system is designed to deliver 15 percent more cleaning capacity generated by a longer sieve stroke and a new front-chaffer extension. This new design increases the cleaning capacity and ensures a cleaner crop in the grain tank even with higher-bushel crops.

Clean grain elevator capacities also have been increased on the 9670 STS, 9770 STS and 9870 STS models to enable growers to harvest more bushels per hour in high-yielding fields.

“Another enhancement to all 70 Series STS Combines is the ease of control and access to precise information for the operator while harvesting,” says Crawford. “The new CommandCenter display screen, mounted on the armrest, provides important harvesting information that is easily viewed in a user-friendly format.”

The CommandCenter display, standard equipment on all combines, provides clear and simple Harvest Monitor yield and moisture information. It also provides text messages from the combine to the operator regarding easy calibration, diagnostics and systems-alert information.

The new 600C corn head is redesigned with higher-speed stalk rolls, larger gathering chains and a more aggressive auger. This translates to greater capacity for handling high-volume crop material, Crawford says. This also keeps more ears in the corn head and more stalks, leaves and trash on the ground. Customers will be able to operate at higher ground speeds with fewer grain losses from the corn head or combine.

“For those growers who want single-pass residue management when harvesting, the StalkMaster chopping corn heads are engineered to meet the demands of tougher corn stalks,” he says. “The new high-performance gear cases on the StalkMaster heads are designed to more aggressively chop and size stalks in one pass.”

In addition to the StalkMaster residue-management system, customers may also choose the new, more aggressive straight stalk rolls, or redesigned longer-wear knife rolls. These two stalk roll options allow customers to select a residue-management system that meets their crop-handling needs.

The corn head row units also are completely redesigned with increased capacity and durability. Gathering chains on the row units are larger and driven by heavy-duty ductile iron sprockets. The row units are propelled with a new drive system that is built to handle the higher speeds and residue management capacity of the 600C Corn Heads.