Date of Award:


Document Type:


Degree Name:

Master of Science (MS)


Plants, Soils, and Climate

Department name when degree awarded

Soil Science and Biometeorology

Committee Chair(s)

V. Philip Rasmussen


V. Philip Rasmussen


Albert Pat Pruitt


Terry A. Tindall


This investigation involved three tillage treatments, fall plowed (conventional) (moldboard IS-centimeter depth), fall chiseled (ripped) (25-centimeter depth), and no-tillage (zero tillage) replicated four times on an established alfalfa field. Rye was planted in the fall and harvested prior to planting the corn. Soil samples contained an average of 5.9 ppm phosphorus in the 0-30 centimeter soil layer, indicating the need for additional phosphorus. Within each tillage treatment, six rows received 11 kilograms/hectare phosphorus with the seed and 34 kilograms/hectare phosphorus side-dressed. Six rows received 45 kilograms/hectare phosphorus side-dressed, and four rows received 0 phosphorus. All 16 rows received 64 kilograms/hectare of nitrogen to ensure it was a non-limiting factor.

Yields were significantly higher in every tillage plot that received phosphorus compared to the 0 kilograms phosphorus/hectare treatments in the plots. There was a trend of higher yields with the treatments of 11 kilograms/hectare + 34 kilograms/hectare side-dressed compared to the 45 kilograms/ hectare phosphorus side-dressed treatments. However, these were not significantly higher.

The no-till plots yielded higher than the ripped or plowed in each tillage treatment. The differences between the no-till and ripped plots were not significant. However, the no-till plots yielded significantly higher than the plowed plot. The no-till 11 kilograms phosphorus + 34 kilograms phosphorus plots averaged 3.1 Megegrams/hectare higher silage yield than the plowed 11 kilograms phosphorus + 34 kilograms phosphorus plots and 2. 5 Megegrams/hectare higher in the 45 kilograms phosphorus side-dressed plots.

Phosphorus uptake was measured by leaf sampling and found to be significantly higher in the no-till plots compared to the ripped and plowed plots. TON and protein were also determined, however, no significant differences existed between any tillage treatments.

The rye was intended to be cut prior to planting for forage use in a dairy or cattle feeding program. Although the average dry weight was only 598 kilograms/hectare due mainly to late planting, this method has great economical potential.