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pasture which received three applications of 100 lb./acre each of ammonium nitrate
during the grazing season (Treatment II). The daily gain (1.73 lb./head) of beef
calves fed corn silage and a concentrate supplement ration in drylot (Treatment I)
was identical to the daily gain (1.73 lb./head) of beef calves fed corn silage
ad libitum on pasture (Treatment VI).

 The beef gains per acre varied from 740 lb. for calves fed corn silage ad
libitum on pasture (Treatment VI) down to 524 lb. for unsupplemented calves on
pasture which received an application of sulfur-coated urea equivalent to 300
lb./acre of ammonium nitrate (Treatment III) (Table 3). The beef gains per acre for
calves receiving the supplemental ration on pasture (Treatment V), unsupplemented
calves on pasture which received three applications of 100 lb./acre each of ammonium?
nitrate during the grazing season (Treatment II), and unsupplemented calves on
pasture which received three applications of 200 lb./acre each of ammonium nitrate
during the grazing season (Treatment IV) were 695, 590, and 534 lb., respectively.
Calves fed corn silage ad libitum on pasture (Treatment VI) had the highest
stocking rate per acre (2.66), while unsupplemented calves grazing the pasture
mixture which received one application of sulfur-coated urea equivalent to 300
lb./acre of ammonium nitrate (Treatment III) had the lowest stocking rate per
acre (1.79) (Table 3).

 The economic data of growing beef calves receiving six different cool-season
feeding regimes are listed in Table 4. The lowest cost of gain ($15.39/cwt)
occurred with calves on Treatment II, followed in order by the cost of gain
($17.90/cwt) with calves on Treatment III, the cost of gain ($18.74/cwt) with
calves on Treatment IV, the cost of gain ($20.20/cwt) with calves on Treatment VI,
the cost of gain ($23.33/cwt) with calves on Treatment V, and the cost of gain
($27.50/cwt) with calves on Treatment I. These costs were not excessively high
considering the inflationary prices which had to be paid for feed ingredients,
fertilizer, seed, fuel, equipment, etc. The large losses per head and per acre
were due to the large negative margin ($19.70/cwt) which occurred between the
price ($55.70/cwt) paid for the light-weight calves prior to placing them on
experiment in the fall of 1973 and the value ($36.00/cwt) of the heavier animals
at the end of the trial (late spring of 1974).

 Under the conditions of this trial, it appeared that the following statements
were justified:

 1. Feeding a 12% crude protein high-energy ration at the level of 1% of body
 weight to calves grazing a mixture of triticale, ryegrass, and crimson
 clover increased gain, but also increased the cost of gain.

 2. Feeding corn silage ad libitum to calves grazing a mixture of triticale,
 ryegrass, and crimson clover increased the carrying capacity (stocking
 rate) and beef production per acre, but reduced average daily gain per
 animal.

 3. Feeding corn silage ad libitum as the energy feed to calves grazing winter
 annual pastures compared to feeding a 12% crude protein high-energy ration
 at the level of 1% of body weight increased the beef production per acre,
 decreased the average daily gain per animal, increased the carrying
 capacity (stocking rate), and decreased the cost of gain.

 4. The application of sulfur-coated urea equivalent to 300 lb./acre of ammonium
 nitrate as a source of nitrogen for winter annual pastures did not provide
 forage for the production of as much beef per acre as three applications of
 100 lb./acre each of annonium nitrate during the grazing season.