or through the skin of the plant. Once within, the mass of threads grows 

 rapidly at the expense of the cells of the host plant, and a diseased condi- 

 tion ensues. Every fungus produces its own characteristic disease and 

 injury, so that it is possible to diagnose the causes of most plant diseases 

 trom the external appearances. 



The best method of dealing with fungous diseases is along the line of 

 prevention of infection. Careful attention to all wounds, when spores may 

 find entrance ; the rotation of crops, so that the resting spores of one crop 

 may not infect the succeeding ones ; careful attention to the destruction 

 of weeds that may be diseased and infect useful plants ; the use of old 

 rather than fresh manures ; the selection of plump, healthy, and disease- 

 resisting seeds; and the timely and early application of fungicides, are 

 some of the methods usually employed to prevent infection. 



Insects do fully as much harm as parasitic fungi, and some are also 

 very difficult to control. Wire-worms, White Grubs, and Root-maggots 

 pass their grub or larval stage in the ground, and feed on the roots of 

 plants. Potato "Bugs," asparagus beetles, and grubs, squash-bugs, and 

 plant lice, feed on the stems and leaves, and are more readily treated. 



For the practical grower, it is important to know that insects are 

 divided into two classes : the biting insects, that chew their food, and the 

 sucking insects. The former can be poisoned by arsenical poisons, but 

 the latter cannot, and must be treated by substances that kill by contact, 

 such as soaps, kerosene emulsions, and tobacco washes. It is also very 

 important to know the life-histories of the most injurious insects, so that 

 they may be attacked during the most vulnerable period of their life. 



Much can be done by such cultural methods as rotation of crops, 

 high culture, careful removal and burning of rubbish and weeds, and 

 plowing. Short rotations, for example, furnish unfavorable conditions 

 for white grubs, wire-worms, and root-lice. The general plan is to 

 change the crop so frequently that it becomes impossible for any insect 

 to pass through its life stages without being seriously disturbed, and its 

 food supply destroyed. Deep fall-plowing is also an excellent method of 

 controlling wire-worms and white-grubs, and is effective against grass- 

 hoppers and cutworms. As for High Culture, it may be said that 

 vigorous, healthy-growing plants are far less liable to attack, and are 

 far more likely to recover from injury, than those that nre in any way 

 weakened in vitality from lack of fertility or by neglect. Therefore, if a 

 farmer and gardener gfives special attention to the fertility and drainage 

 of his land, procures the best seed, and by proper planting and cultivation 

 secures vigorous plants from the start, and by proper care endeavours to 

 keep them in this condition until the product is matured, he will have 

 accomplished more in preventing loss from insect depredations than he 

 would accomplish by the best remedies applied to half-starved, neglected 

 plants. 



