4 
INSECTS AND INSECTICIDES. 
In some cases insect ravages are due to an unthrifty 
condition of the plant attacked, the result of soil exhaus¬ 
tion, or other untoward conditions resulting in stunted 
growth, which invites their attack. 
Cabbages and cauliflower, if grown in soil lacking in 
available plant food, are soon overcome by the aphis 
peculiar to them. Beets, if grown in soil rendered hard 
and impervious by irrigation and lack of cultivation, soon 
become a prey to insect attack, whereas had the con¬ 
ditions been favorable these plants oftentimes overcome 
their insect enemies by their own inherent vigor. It pays 
therefore to have healthy, vigorous plants only, to keep 
them doing their best during the growing season, and to 
adopt a judicious rotation of crops. 
INSECT LIFE. 
Before considering remedies in detail we will first 
notice the four stages in insect life, commencing with the 
egg, trom which hatches the larvse commonly known as 
grub, caterpillar, maggot, etc. It is in this stage that in¬ 
sects are most injurious, feeding voraciously until they 
have attained full size, when they change their form, 
cease to eat and enter the third stage, when they are called 
pupse. 
Having remained in this stage for a greater or less 
length of time, they burst their cases and emerge perfect 
insects to lay eggs and begin again the same round of 
life. 
In some cases these changes are well marked; in 
others the transformations are less complete, as in the 
case of plant lice and grasshoppers. 
ARSENICAL POISONS. 
The various forms of arsenic are beyond doubt the 
most practical insecticides known to science, especially 
Paris green and London purple. White arsenic should 
never be used, because its color is apt to lead to fatal 
