han a large number poorly fed, will bring
in a steady income, that will do much for our farmers in their present
conditions," advised County Agent Derr.[149] He also hoped to see
farmers concentrate on the butterfat content of their milk and to
increase their production of cream for which there was a continual
market; the skim milk left after the removal of cream could be fed to
calves, pigs or children. Most often Derr cautioned against the dangers
of complete specialization at the expense of an integrated farm in which
each facet of the farm was both aided and benefitted by every other
part. "The old slogan, 'the cow, the sow and the hen,' is a very true
one," he wrote, "especially in the South."[150]

Derr did well to emphasize the quality of milk products. A 1932 ruling
in the District of Columbia requiring a 4% butterfat content in milk
sold there occurred just as Derr was complaining that "with many the
quality of the milk is not such a vital question as the quantity."
Holstein cattle, which gave higher yields but less rich milk than did
Jerseys or Guernseys, predominated in the county, making the new demand
a difficult one to meet. In desperation some farmers tried
cross-breeding the two strains with mixed results; the inevitable
outcome was to compromise the county's movement towards establishing
herds of pure-bred animals.[151]

The mixing of breeds to increase butterfat content was not the only
element which undercut the breeding program. One problem, the selling of
highly profitable animals, was yet another hazard of success. "Owing to
the excellent reports being made by our cow testing associations,
numerous buyers from other states have come into the county and by
paying almost fabulous prices have taken away quite a number of our best
animals," Derr wrote in 1926. "In some cases this has proved a costly
undertaking for our dairymen, as by bringing new animals into their
herds ... either T B or abortion has been introduced."[152] Another
factor working against pure-bred stock was the depression, which for
farmers encompassed not only the 1930s, but the entire period following
the deflation of World War I prices. With less cash available, many
farmers bought poor quality bulls rather than invest the money for a
pure-bred animal.[153]

Notwithstanding these setbacks, dairy farming continued to be Fairfax
County's predominant (and most prestigious) industry during the 1920s
and 1930s. Indeed, it flourished