AGBICULTURAL EXPERIMENT STATION. 243 



253 graiDS of the poison per tree. Now supposing half of it fell 

 upon the fruit and half on the leaves and branches, and the tree 

 bore ten bushels of apples, this would make 13 grains to a bushel 

 of fruit. There are about 200 ordinary sized apples in a bushel. 

 This -would leave only seven one-hundredths of a grain to an apple 

 which is much less than a poisonous dose. Considering that the 

 poison is applied when the fruit is small and long before harvest, 

 and that the rains would wash much of it off, the danger of poison- 

 ing is small. 



5. In dusting vegetables or plants with drj^ poisons care should 

 be taken not to inhale them. See that the dry dust is not carried 

 by the wind to berries, vegetables or fruit soon to be gathered. It 

 is best not to plant berries or vegetables near orchards or shrub- 

 bery that have to be sprayed. 



Conditions. 

 To have insecticides work properly the material must be good 

 and the application properly made. 



1. As there is considerable adulterated material on the market 

 it is best to procure poisons, even at a higher price, from reliable 

 dealers who will warrant their goods. 



2. Great care should be exercised in properly mixing the mat- 

 erial. "When it is only held in suspension and not soluble in w'ater 

 it should be kept thoroughly stirred while being applied. 



3. The application should be by an even fine spray and with 

 force enough to reach every part of the tree or plant. 



4. If the material seems to burn the leaves it is too strong 

 and should be diluted. 



5. The proper time to spray is of great importance. It should 

 be done when the insect, or fungus is in the proper stage of its 

 life to be reached by the poison. 



6. If a hard rain follows the spraying it should be repeated. 

 Several applications are often necessary during the season. 



Common Insecticides. 



The injurious insects that can be destroyed by the application of 

 insecticides are of two kinds : Those provided with biting jaws for 

 t ating the foliage of plants, and those provided with sucking appa- 

 ratus and living upon the juices of plants. Those having biting 



