Crop Sciences

AGRI-NEWS - Issue 23 - 01, January, 2002

• Coming Events
• December Summary
• Weather
• Crop Report

Coming Events

• Jan. 21 - Office Closed M L King Day
• Jan. 14 - ORR Corp. Officers meeting, 2:30 PM

Weather: As we close out the record books on another year, we find very few things to say that are detrimental to this past month. The lack of rainfall, and or snow cover could be a debating issue. We recorded 13 days with precipitation and only 5 days with snow/flurries. We had 9 days with air temperatures greater than 50 degrees, and 2 days when the low temperature was less than 10 degrees. Both the high and low temps were 6 or more degrees above the Normal. Only two years, 1982, and 1979 were warmer for the month of December. Our soil moisture tubes have been dry since June 25th. With 12 rain events of 1 to 1.99 inches, and only 3 events of 2 to 2.42 inches, one can see that moisture percolation into the soil profile has been limited.

Crop Report: The lack of snow cover, and the generally warm temperatures are causing some concern for the degree of dormancy our crops have developed. When temperatures range in the upper 40's to low 50's, and surge occasionally into the mid 60's, ornamentals, trees and wheat growers become concerned. Most of the wheat varieties look good, and growth has been good this fall. The degree of dormancy has me concerned should a sudden cold snap linger without any snow cover for protection. The deer have not bothered the varieties to date. The open winter thus far has allowed ample grazing in corn fields and timber areas.

Research Results: The tables below represent the Potassium Rate Study 4 year average yields for Continuous Corn and Rotation corn. Continuous Corn yields have lagged behind the Rotation Corn at all treatment rates. (See the numbers in blue, with an asterix (*), that represent the "Old" treatment rates without the build up and draw down treatments.) During the past four years the 300 lb/A treatment in the Rotation Corn has not performed as we would have expected. Some of this discrepancy in yield is due to wildlife damage to the plots. From the results in Table 1, we can see that the Old 100/New 100 treatment has done fairly well, even at relatively low soil test levels. Rotation Corn, (Table 2), appears to peak at the Old 0/New 100 treatment, however, the average across all the New treatments favor the Old 200 lb/A treatment. As the New treatments increase, so do the yields. From this data, we see a clear advantage for the rotation of corn with soybeans.

Soybean yields in this study, Table 3, have not varied much during the past four year. The average of the New treatments shows little difference among the Old treatments. Growth differences have been noted among treatments during the growing season; however, little variation in yields has been noted. Leaf discolorations have been seen on the Old 0/New 0 treatments for several years. By mid-August, the leaf discolorations have disappeared.

This study has shown over the years that low levels of potassium can consistently produce good yields of corn and soybeans. However, once the soil test levels commence to drop under the 200 lbs/A K2O, then we start to see plant health problems. These lighter colored timber soils can produce good yields provided they are managed properly. If soil tests are high, then a reduction of applied K2O can be made without appreciably reducing yields. In many cases, yields may increase.

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