Feb. 16, 1914 
Winter Spraying with Nitrates 
443 
Comice. —The major portion of the block was sprayed with a plain water solution 
of nitrate of soda at the rate of 1 pound to the gallon. A small portion was sprayed 
with commercial lime-sulphur solution, diluted 1 to 9, with nitrate of soda added 
at the rate of 1 pound to the gallon of diluted spray. Through a misunderstanding 
the men doing the spraying left no check rows in this block, so that crop data couln 
not be obtained. However, Mr. Reed’s exact knowledge of the previous productiod 
of this block as a whole indicates that the marked increased production this last 
season was more than probably due to the nitrate spraying. The Comice is a rela¬ 
tively shy bearer, and a valuable pear commercially, so that any increased production 
that could be obtained by nitrate spraying would be much appreciated by the 
grower. One portion of the block that regularly produces less than the remainder 
gave a good crop this year, and it appeared that the addition of the lime-sulphur 
solution augmented the effect of the nitrate of soda just as the addition of lye has 
done in the experiments of the writers. 
GlouT Morceau. —A block of Glout Morceau pears was sprayed with the combi¬ 
nation of lime-sulphur solution, diluted 1 to 9, plus nitrate of soda 1 pound to the 
gallon of diluted spray. This block had never produced a full crop, and while no 
unsprayed checks were left, the increased production this year would appear to be 
due to the nitrate spraying. 
"Winter Nelis.—A block of Winter Nelis pears was sprayed with a solution of 
nitrate of soda 1 pound to the gallon of water. No lime-sulphur solution was added 
in this case. No check rows were left, and a frost destroyed a large percentage of 
the fruit after it had set. However, at that time the trees were carrying the largest 
crop they had ever produced, and again it would appear that the nitrate spraying 
had had a beneficial effect. The trees came into bloom about 10 days ahead of 
normal opening period. 
DISCUSSION OF RESULTS AND SUMMARY 
It is not the writers' intention to convey the impression that dormant 
spraying with nitrate solutions will solve the problem of shy bearing of 
fruit trees nor offer a more advisable method of applying nitrogen 
fertilizer. The purpose of this paper is simply to present the results 
as they now stand. 
It is evident that, at least under certain conditions, some varieties of 
apples and pears that are more or less self-sterile may have their crop 
production materially increased by dormant spraying with solutions of 
nitrate of soda plus lye. The combination of a solution of nitrate of soda 
and lime-sulphur is apparently capable of bringing similar results. 
Actual quantitative data on increased production from spraying with a 
solution of nitrate of soda are available from only one source, that of 
the first experiment on Yellow Bellflower apples in 1912. No production 
records were obtainable from the various tests made by growers during 
the season of 1913, but the one test on Yellow Bellflower apples and 
several others on pears indicate that such an increase had undoubtedly 
been brought about. It is considered that the growers' knowledge of 
the crops of the previous years as compared with that of this year fur¬ 
nishes a basis for conclusions that are at least corroborative. 
That nitrate spraying of dormant trees will bring about an earlier 
blooming of certain varieties of fruit is a satisfactorily established fact, 
which has been demonstrated on Yellow Bellflower apples at Watson¬ 
ville, Cal., and on various varieties of pears at San Jose, San Juan, 
and Suisun, Cal., during the past season. How generally this statement 
will apply to other varieties of apples and pears and in other localities 
remains to be determined. Results on stone fruits have not been as 
striking as those on pears and apples, but it is possible that stronger 
solutions, earlier spraying, or a repetition of the spraying in successive 
years may bring about such results. 
