Record cold temperatures descended upon much of the country last weekend and left many crops, from citrus trees to winter wheat, with potentially substantial damage.

According to the Department of Agriculture's weekly weather and crop bulletin, temperatures reached the freezing point as far south as New Mexico, Texas, Mississippi, Louisiana and Georgia. Temperature readings less than 20 degrees were seen as far south as Colorado, Kansas and Missouri.

These extreme cold temperatures may have caused devastating damage to winter wheat crops. The Agriculture Department's weekly crop progress and condition report showed that winter wheat acreage considered good or excellent (an indication of average to above-average yields at harvest) declined from 71 percent to 64 percent.

Despite this reduction in crop condition, the acreage considered good or excellent is still higher than the 10-year average of 58 percent. This reduction in high quality acreage may be an early indication of lower yields for wheat crops come harvest, though the true extent of any damage may not be known for several weeks.

Wheat traders pushed prices higher throughout the week as a result of the cold with prices rallying 2.5 percent on the week as of Wednesday's close and continuing the rally into Thursday.

Traders will be waiting anxiously for more data from farmers and the Agriculture Department during the next several weeks in order to determine the actual amount of damage.

CORN: The cold weather had a minimal effect on corn futures, although some corn was damaged in the south. Instead, corn traders looked ahead to an improved weather forecast during the next week calling for drier weather as a bearish sign for corn, which pressured corn prices lower this week.

Corn plantings will begin in earnest very soon throughout much of the country, and the improved forecast led traders to believe that many plantings will go smoothly and on schedule.

Of note though, is the recent snow in the Northern Plains.Much of the Dakotas, Minnesota, Iowa and Wisconsin saw snow showers over the past week, leaving farmers with little choice but to wait for it to melt before working their fields.

If this snow melts slowly and delays farmers' corn plantings, it could require their crop to pollinate during the hottest part of the summer and increase the chances of frost damage in the fall. Indiana corn farmers usually have planted 5 percent to 10 percent of their corn by mid-April, but this year have planted none.

ENERGY: Energy prices were very volatile over the past week. Crude prices dropped by $2.77 per barrel on Monday as the risk premium created by the capture of 15 British sailors by Iran was worked out of the market.

After this Monday decline, crude rallied throughout the week, pulled higher by a rally in gasoline futures. Gasoline futures, despite a drop on Monday, rallied to fresh calendar-year highs on Wednesday after the Energy Information Administration reported a second consecutive week with significantly larger than expected draws on gasoline inventories.

Though the report also showed that refinery utilization increased by 1.4 percent for the week, capacity utilization is still recovering very slowly due to unscheduled shutdowns at several refineries. This weekly report from the EIA will be watched very closely as the U.S. heads into the summer driving season.

Walt Breitinger is vice president of commodities at A.G. Edwards and Sons. He can be reached at (219) 738-6460.