Geographical Areas

1. Summer growing season of at least l50 days.

2. Mild to cold winters.

3. Precipitation varies from about 800-1500 mm/yr.

• Greater portion coming during the warm season

5. Most of zone between 35o and 55o latitude.

6. In Europe:

• Most of Europe except Spain, Portugal, and part of Italy
• Western USSR

• Northern Japan and part of Korea
• Much of Northern China (30o-50o N)
• Small areas of Australia and N. Zealand

• Bounded on west by 98th meridian and on south by 37 parallel
• Includes S. Canada, corn belt

1. Generally highly productive.

2. Primarily mollisols and alfisols.

3. OM generally high.

4. Mildly to highly acid/requires lime.  

Current Crop Production Systems

1. U. S.

• Corn, soybeans, and forage crops

3. Changes appreciably in past few decades

• Synthetic nitrogen
• Soybeans became a major crop

• Increasingly more concentrated, confinement housing
• Unusual to find dairy, beef, and hogs on same farm

• But some land best fitted for only corn or soybeans
• Much in continuous corn or soybean

• 5 states (IL, IN, IA, MO and OH) produce % world's corn

• % U. S. beans in corn belt

• Harvest too late for double cropping

10. Summer rainfall and temperatures conducive to high forage yields.

• Forage not consumed on farm marketed as hay
• Forages more important in other world locations in this zone

• High degree of insect and disease resistance
• High plant populations
• Chemical weed and insect control

1. Higher proportion of land is devoted to wheat, oats, barley, rye, sorghums and millet

• Only in France, Italy, and China is corn as much a 1/4 total grain

3. Livestock account for large part of gross farm revenues than in U. S.

• 40% in Sweden

• Among highest yields in world

6. Higher proportion of land devoted to forages.

7. Crop rotation is followed more regularly.

8. China multiple cropping and intercropping at very high intensity.

• As many as 12 crops in single season.
• Wheat second only to rice in area grown
• Corn primary crop in northern China
• Grown in combination with wheat and soybeans
• Soybeans grown throughout country

10. Some of most productive parts of USSR in this zone.

• Ukraine
• Climatic and topographical limitations allow only 1/4 of zone to be farmed

12. Ukraine more subject to drought than corn belt.

13. Rotations generally followed in USSR.

• 8 or 6 field rotations

• Effects 20% of ag land in USSR to moderate to severe levels

1. Most common is excessive moisture.

• Wet spring delays timely planting
• Planting often optimum period may result in serious decrease in corn and soybean yield
• Ponded water

• Almost every year, one or more periods when crops suffer from moisture stress

1. Cropping systems.

• Increase portion of year crops may be grown
• Increase output per unit of land during major growing season
• Double cropping wheat and soybeans
• Seeding new crop before harvest of previous crop may help extend double crop further north
• Seed via airplane
• Success dependent on soil moisture
• Development of better yielding shorter season soybeans and earlier maturing wheat

• Reduced or conservation tillage offers many advantages
• Conventional soybean tillage requires 3 times labor and 8 times fuel of no-till system
• Increasing popularity of reduced tillage has only come after progress in planter development
• Adequate chemical weed control essential
• Zero-tillage systems depend on killing previous crop with chemicals
• Accentuate need for adequate insect control practices

• Spreading the water more uniformly over the surface ensures more uniform infiltration and maximized the depth of wetting from rain
• Prevents ponding

• Subsurface drainage must be followed on many soils in this zone
• Many fine textured soils have inadequate drainage and are slow to warm in spring
• Why moldboard plowing still so popular in corn belt
• Loss of more soil and water
• Development of more powerful tractors
• Made it possible to plant timely
• Increased compaction

• Increasing in humid areas
• Primarily in areas where ground water is available in adequate quantities
• May be more advantageous to invest in irrigation equipment to increase and stabilize production than to purchase new land
• In Illinois, corn yield increased 6T/ha with irrigation when mid-summer rainfall unusually low

• Soil testing needed to maintain fertility and obtain satisfactory yields
• Lime needed on most soils
• Net downward flow of water through the soil profile leaches cations
• N provided by decomposing soil OM and plant residues not sufficient for high yields on non-legumes
• 2.2 to 2.4 kg of N/100 kg of corn produced in IL

• Include weed, insect, and disease control
• Knowledge of the weed species, coupled with knowledge of tolerance crop and weeds to specific chemicals necessary for good weed control
• Use of resistant varieties is always good protection against diseases and insects
• Rotation of crops important for pest control
• Control of pests by chemical/and/or biological means essential for high yield
• Chemical control most common

• Soybeans and corn harvested by combine
• Improvements in combine heads in horizon for soybeans
• Take individual rows into combine
• Ability to harvest crop quickly most important in zone where rainfall may delay harvesting
• Drying corn by blowing heated air through it following harvest allows harvesting at earlier date
• Requires expensive equipment and energy costs may be high