414. ReEeporT OF THE HorTICULTURAL DEPARTMENT OF THE 
and pears in particular, to secure cross pollination and without 
resulting crops of fruit, doubt the value of such plantings, holding 
that the disadvantages of mixed planting outweigh the advan- 
tages. A prominent German experimenter,’ after several years 
of investigation, denies that there is any gain in the setting of 
truit in mixed plantations of apples and pears. ‘There is there- 
fore a controversy as to the necessity of cross-pollination for the 
setting of apples and pears and this shows that there is need of 
further investigation to determine with greater certainty why 
orchard trees so often fail to set fruit when there is an abundance 
of blossoms. 
Admitting that self-sterility with a lack of cross-pollination 
is a cause of failure of many plants to set fruit, all agree that 
there are other causes; as, weather; age and vigor of plant; the 
individuality of the plant; and plant environment whereby food, 
moisture, light and other conditions are affected. 
One cannot read the records of fruit growing in New York 
without concluding that among these, unfavorable weather is 
the predominating factor in the loss of fruit crops during blos- 
soming time; in fact that weather exerts a controlling influence 
far more powerful than all other causes. Unfortunately there 
seems to have been but little investigation to show the relations 
of weather to the setting of fruit; and because the deleterious 
effects of unfavorable weather have not been more carefully set 
‘before the fruit-grower, and because of the impossibility of con- 
trolling weather conditions, the important relationships of weather 
to the setting of fruit are largely overlooked in orchard practice. 
The fact that weather cannot be controlled is not sufficient 
reason for this neglect. Inquiries as to the nature and influence 
of atmospheric agencies at blooming-time should be helpful in 
many ways: In determining causes of failure; in selecting sites 
for orchards; through a study of the relation of weather to the 
setting of fruit for a past period we shall be able to forecast the 
future with more assurance; and through more accurate knowledge 
of the weather and its relationship to the setting of fruit the 
orchardist can better prevent the evil effects of bad weather. 
There is much to lead us to believe, too, that the stresses of. 
weather, of cold and heat, of wetness and dryness — which we 
have in eastern and central United States, largely account for 
*Ewert. Blutenbiologie und Tragbarkeit unserer Obstbaume. Landw. 
Jahrb., 35: 258-287, pls. 2. 1900. 
