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In the case of bearing orange trees it would appear that the season 
of the year when they could be sprayed with the least amount of in- 
jury to themselves and with the greatest fatality to the red scales infest- 
ing them would be at a time when they were in blossom, after all of 
the fruit of the preceding season had been removed from them. There 
would at such a time be no fruit on the trees for the seale-insects to 
locate upon, so that all these insects that could be reached by the spray 
would be destroyed without at the same time injuring any portion of 
the tree. Several persons who had sprayed their orange trees at a time 
when the latter were in full bloom informed me that to all appearances. 
none of the blossoms were injured by the spray, providing that the 
latter was not used so strong that it injured the leaves, being unani- 
mously of the opinion that the blossoms were_as hardy as the leaves. 
The young fruit is much more susceptible to the effects of the spray than 
are either the leaves or the blossoms, and this is the ease until it becomes: 
at least half-grown. It has been my experience, and also the experience 
of others with whom I have conversed upon the subject, that where the 
conditions are equal an orange tree is more susceptible to the effects 
of a given spray than a lemon tree, the foliage of the latter being 
hardier; whereas in the case of frosts the reverse of this is true. lemon 
trees being greatly injured by frosts that would produce little or no 
effect upon orange trees growing under similar conditions. 
It is a well-established fact that any given spray will not be so fatal 
to the scale insects during the cooler portion of the year as it will if 
applied during the hotter portion. On this account it will evidently be 
found necessary during the winter months to use a somewhat stronger 
solution than indicated in the formula given above ; and probably the 
proper proportions to use during this season would be obtained by ad- 
ding water sufficient to make only 80 gallons, instead of 100 gallons as 
given in the above formula. 
What is true in regard to the effects of the solution upon the insects. 
is equally true of its effects upon the tree, the same solution that would 
not injure the tree if applied during cool weather might injure it very 
severely if applied during very warm weather. As bearing upon this 
subject, I can not do better than to give the experience of one of my 
correspondents, Mr. F. G. Ryan, an intelligent orange-grower of 
Anaheim, in the adjoining county of Orange. .Mr. Ryan used the resin 
compound quite extensively for the destruction of the Black Scale 
(Lecanium olee Bernard), and under date of February 7, 1889, he writes. 
me as follows: 
I want to tell you of a disappointing experience I had with the resin compound. 
On January 21 and 22 I sprayed twelve trees in one quarter of the grove and eight in 
another with a compound composed of 1 pound of caustic soda, 8 pounds of resin and 
32 gallons of water. Afier doing this a hot, drying wind arose and stopped our work. 
The wind continued for several days, becoming milder each succeeding day, and on 
the fourth day I noticed some leaves dropping from these trees; this dropping of the 
foliage has continued and increased until now there is scarcely half the foliage left 
