V Ifciztzzckgj Agricultural Etrpcrimeizt Station. 37
2%,510,000 blank fertilizer tags have been issued and stamp
sales numbered 1,387,908, the latter representing 85,201iA tons
` of fertilizer.
V · Air and Soil Temperatures. During the past year com-
‘i plete records have been kept of air and soil temperatures, the
latter at 3 inches and 18 inches daily and 36 inches weekly.
  Thermographs suitably exposed on the Experiment Station
il`arm were relied upon for a continuous record, but were check-
  ed frequently with mercury thermometers.
· The soil 1ln—rnr:;·graplis were lozeated in a iield ol' reel clover _
· until the elith week, when they were moved to a plot free of
- vegetation for the remainder of the period. lt will be observ-
ed that the soil temperatures at 3 inches exceeded or equaled
_the air temperatures from the 25th to the 35th week. As the
clover was cut for hay during the 24th week, this may have
V permitted the higher temperature at the 3-i11ch soil depth.
Vllowever, the second growth of clover, tho rather thin in cover,
had reached 6-8 inches by the 29th week without affecting this
relation. The time at which this temperature again dropped
_ lower than the air temperature is identical with the first heavy
rain which fell after the early summer. As the summer had
been very dry, this may indicate that the soil moisture was a
more important factor than tl1e vegetative covering in this re-
_ lationship. The average weekly temperatures are shown in ‘
the following table: