ff. 
and other places on the farm except 
inside dairy barns and milk rooms. 
However, owing to the uncertainty of 
obtaining satisfactory results with this 
insecticide, lindane, chlordane, toxa- 
phene, or methoxychlor may prove 
more effective. 
Since several kinds of insecticides 
are now recommended for use on dairy 
cows and other livestock and in farm 
buildings, and since the effectiveness 
of these materials may vary depending 
on local conditions, the dairy farmers 
should keep informed of local recom- 
mendations issued by county and State 
specialists. 
Treatment of Dairy Cows 
Control of Horn Flies. --Since the 
horn fly spends most of its life on the 
animal, it can be controlled readily 
with the new long-lasting insecticides. 
It breeds infreshcattlé droppings, and 
onmost farms destruction of its breed- 
ing places is impractical. 
Methoxychlor may be used for horn 
fly control in the same way and at the 
same concentrations formerly recom- 
mended for DDT. It can be obtained 
in wettable-powder form and as an 
emulsion concentrate. To preparea 
0.5-percent spray, mix 8 pounds of 
50-percent wettable powder in100 gal- 
lons of water, or about 6 1/2 ounces in 
5 gallons. Emulsion concentrates con- 
tain 25 percent of methoxychlor., To 
make a 0.5-percent spray, add 2 gal- 
lons of concentrate to 100 gallons of 
water, or 0.8 pintto 5 gallons. Apply 
