Excessive rainfall in September is eroding yield expectations for Mid-South corn and cotton crops, according to USDA’s Oct. 9 Crop Production Report.

The report, an assessment of crops as of Oct. 1, reduced expected corn yields by 7 bushels in Mississippi, 2 bushels in Louisiana and Arkansas, while raising it 1 bushel in Tennessee. Forecast cotton yields declined in every Mid-South state except Missouri.

U.S. cotton production is forecast at 13 million bales, down 3 percent from last month but up 1 percent from last year. Upland cotton production is forecast at 12.6 million bales, down 3 percent from last month but up 2 percent from last year.

While producers in the Delta region are expecting decreased yield due to excessive amounts of rainfall received during September, upland growers in Alabama and Georgia are expecting record high yields. The American-Pima production was forecast at 367,000 bales.

U.S. corn production is forecast at 13 billion bushels, up slightly from last month and 8 percent higher than 2008. Based on conditions as of Oct. 1, yields are expected to average 164.2 bushels per acre, up 2.3 bushels from September and 10.3 bushels above last year.

If realized, this yield will be the highest on record and total production will be second only to the record set in 2007. Yield forecasts remained unchanged or increased from last month across the Corn Belt, Great Plains, and Ohio Valley where warm, dry weather during much of September helped push the late-developing corn crop towards maturity.

Light frost was reported in parts of the northern tier of the Great Plains and Corn Belt in late September. However, temperatures were not considered low enough to terminate crop growth. Farmers now expect to harvest 79.3 million acres for grain, down 1 percent from the September forecast but 1 percent above 2008.

Meanwhile, the U.S. rice crop appears to dealing with the wet weather, although soggy fields are slowing harvest. Forecast yields rose from last month in every rice-producing state except Arkansas, which remained the same at 6,800 pounds per acre.

Soybean production is forecast at a record high 3.25 billion bushels, up slightly from the September forecast and up 10 percent from last year. Based on Oct. 1 conditions, yields are expected to average 42.4 bushels per acre, up 0.1 bushel from last month and up 2.7 bushels from 2008.

If realized, this will be the third highest yield on record. Compared with last month, yields are forecast higher or unchanged in all states except Michigan, Mississippi, Ohio, and New York.

The largest decrease in yield from the September forecast is expected in Mississippi where persistent rain during the last two weeks of the month increased the potential impact of disease.

Increases of 2 bushels are expected in Kentucky, Louisiana, Oklahoma, and Virginia. If realized, the forecasted yield in Alabama, Georgia, and Nebraska will be a record high and the forecasted yield in Arkansas, Kentucky, North Carolina, and Pennsylvania will tie the previous record high.

Area for harvest in the United States is forecast at 76.6 million acres, down slightly from the previous estimate but up 3 percent from 2008.

e-mail: erobinson@farmpress.com