570 
JOURNAL OF ECONOMIC ENTOMOLOGY 
[Vol. 17 
ing from March 20th to April 1st presages a fair crop and a bloom after 
the first part of April means a poor crop. On the whole this seems to 
hold good. 
Disadvantages 
Some growers argue that the sprays will hasten the bloom so much 
that it will make them more liable to injury from frost. This has not 
been noted in the Santa Clara Valley by the writer, but this might 
happen once in a great while with some varieties of fruit in certain 
localities. If one does not want to obtain the early bloom he can spray 
rather late and clean up his trees from pests with practically no stimu¬ 
lation ordinarily. 
Others argue that there will be a reaction to excessive stimulation, 
yet nothing of the sort has been noted to date on orchards that have had 
an annual treatment for four and five years in succession. In com¬ 
parison, there are non-poisonous stimulants, such as spirits of ammonia, 
administered to human beings with no apparent detrimental reaction, 
so that the same should apply to plants as well. 
Excessive dosages of spray material may cause a retardation instead 
of a stimulation when applied under some conditions. This is to be 
expected as it is true of practically any stimulant when applied too 
freely. 
Advantages 
Some growers are spraying with an oil spray every season in order to 
obtain the benefits to be derived therefrom. This applies particularly to 
prune, apricot, and cherry growers. 
1. The early bloom causes the fruit to set before the Thrips appear, 
thereby giving more and cleaner fruit in sections where this insect is a 
problem. 
2. The spray causes the foliage to grow very fast, covering the 
small fruit and protecting it from sunburn and frost. 
3. Moreover, the fruit attains much of its growth before the natural 
moisture has evaporated from the ground. 
4. The early vigorous bloom produces an earlier harvest, thereby 
reaching the market in time for better prices. 
5. It will cause larger crops of larger fruit. This is probably due 
partly to having the tree free from pests, thereby being able to function 
properly; partly to obtaining its growth early before the hot weather 
sets in to retard it; partly to the large dark green leaves which the tree 
obtains early; besides the direct effect of the stimulation. 
