Soils are predominantly gravelly loam with loam and clay soils in some of the fields.
Sprinkler-irrigated malt barley.
Variable-rate applied fertilizer for three years.
Before variable-rate fertilizer application:
Soil tested yearly:
a. Applied 160-180 pounds 46-0-0 ($335 per ton for 46-0-0).
b. Applied 50 pounds 11-52-0 when seeding ($335 per ton).
Fertilizer cost was $28.47 plus $8.38 = $36.85 per acre.
Protein for malt barley was near the 13.5 percent cutoff for acceptance by brewer.
With variable-rate fertilization application:
Producer hired a Technical Service Provider (TSP) to provide technical expertise for variable- rate application of fertilizer.
TSP obtained satellite imagery of growing crops a couple times a year to develop zones. The zones closely followed the existing soil map of the fields. The zones were soil tested based on the satellite imagery. Cost of satellite imagery was $11.00 per acre the first two years and $5.00 per acre the third year.
a. Applied 80 pounds 46-0-0 ($335 per ton).
b. Applied 90 pounds 20-20-10 ($329 per ton).
Fertilizer cost was $13.40 plus $14.80 = $28.20 per acre
Fertilizer application costs were $1.50 per acre higher
Year one had a five bushel higher yield. Years two and three had no yield change.
There was a major improvement in quality of the malting barley in terms of plumps, thins, and protein. Protein levels were around 12.5 percent. Gravel knobs produced 40 bushels per acre as compared to previous years when they produced little grain.
Fertilizer savings of $8.65 per acre.
Increased fertilizer application costs of $1.50 per acre.
Cost of satellite imagery of $11.00 per acre for the first two years and $5.00 the third year.
Five-bushel yield increase the first year, and no change the second and third year.