availability were analyzed in order to calculate total nutrient
uptake. Analytical data for forage from the third harvest (Au-
gust) of each year are presented in Table 9. Data from this
harvest were selected because Pensacola bahiagrass was domi-
nant, and its highest rate of growth occurs during the July-
August period. In 1971, forage yields at the third harvest were
affected primarily by N fertilization. Yield and forage N were
relatively low from Treatment 1 where N was omitted. Another
marked difference was higher K concentration in forage from
treatment 3 which received K fertilizer. However, minimum
forage K concentrations during 1971 probably did not limit
yields; Gamon (7) showed that the critical concentration in oven-
dry Pensacola bahiagrass was near 0.6%. Differences in concen-
trations of other elements were not large and none approached
deficiency.
 In 1972, the N fertilizer rate was reduced to 200 pounds per
acre due to some sod deterioration from the 400 pounds per acre
rate used in 1971. Forage yield and N concentration were lowest
from Treatment 1. Forage yield and K concentration were low
for Treatment 2 without K fertilization in comparison with
Treatment 3. Other nutrients were adequate, though there were
significant differences among them.
 In 1973, yield, and N and K concentrations were again ex-
tremely low from Treatment 1. Forage K concentration was
only 0.44% from Treatment 2 and yield was severely depressed.
At the fourth harvest it was only 0.33 %. Forage N concentra-
tion from Treatment 2 was significantly higher than from other
treatments which emphasized the deficiency of K. Phosphorus
and S were in adequate concentrations in forage throughout the
experiment. Significant differences in concentrations among
other elements occurred, but none was in the deficient range. Of
interest was the increase in forage Mn concentration with years.
Nitrogen and other fertilizer salts added during this experiment
probably caused a reduction in pH at the soil surface. The avail-
ability of Mn increased as indicated by higher concentration in
forage from comparable harvests. Forage micronutrient con-
centrations from Treatment 3 were also influenced by annual
application of the frit.
 Forage yields were high for the 3-year experimental period
which placed considerable stress on soil nutrient supplies. These
soils without N fertilizer mineralize 30 pounds N per acre per
year. Uptake of N in forage from Treatment 1 exceeded this
amount each year (Table 10). Some of this N was fixed symbio-