r and cover-crop experiments. The
summer of 1923 was extremely dry. This was followed by warm rains in the
late fall and early winter. On January 6, during a period of high wind,
the mercury dropped to within a few degrees of zero, official reports
recording temperatures of from 6 to 8 degrees above zero at various
nearby stations.

On March 31, Dr. J. J. Skinner, of the Office of Soil Fertility
Investigations, in attending to the spring fertilizer applications,
discovered that a high proportion of the trees had been badly winter
injured, as indicated by the usual characteristic evidence. These
included a considerable exudence of sour and frothy sap from the trunks
of the trees, particularly those having smooth bark. This invariably
occurred on the west side. Shot-hole borers, which not infrequently
follow such injury, were already at work.

This situation was at once called to the attention of the owner of the
orchard who lived some 50 miles away. He replied that although he made
frequent visits to the orchard, the matter had not attracted his
attention, nor had it been reported to him. On April 17, he inspected
the orchard and the day following, reported to the Bureau by special
delivery that as a result of a rather hasty inspection, he was convinced
that from 16 to 20 per cent of the trees in the experimental tract were
injured, but that in the rest of this orchard the injury was
insignificant, probably not exceeding 4 per cent. His not unnatural
deduction was that the high fertilization of the soil in the
experimental tract had caused tender growth which, under the extreme
conditions of the previous months, had been unable to survive.

On April 24, a careful record of the condition of all trees in this
tract and of a representative number of those in adjacent parts of the
orchard, was made by Mr. J. L. Pelham of the Bureau of Plant Industry
and the writer, in company with the owner of the orchard and his
superintendent. It was found that in the experimental tract, 50 per cent
of the trees had been visibly injured, thus exceeding the owner's
maximum estimate by about 30 per cent. Of the total number of trees, 20
per cent were regarded as being slightly injured, and 30 per cent
severely so. Of the fertilized trees within the experimental tract, 55
per cent showed injury to some degree as compared with 58 per cent of
the trees unfertilized, also within the tract.

Inspection of the trees outside of the experimental