436 Other Management of the Vegetable-Garden 



Insects that feed openly on the tops of plants are usu- 

 ally amenable to direct treatment with poisons or other 

 sprays. Of this class are potato-bugs and plant-lice. 

 Those troubles that appear in the inner parts of 

 plants or in their roots are not open to direct treatment, 

 and in such cases the general management of the place 

 must be relied on to keep the enemies in check. Insects 

 and diseases are incidental or secondary facts in every 

 garden plantation. The primary thing is to make the 

 plants grow; the secondary thing is to keep the bugs off. 

 One's attitude toward these invaders must be the same as 

 that toward weeds: one must rely first on management. 



In these popular writings, many other creatures are 

 naturally included with insects, as millipedes, slugs, nema- 

 todes, sowbugs, and mites; but the general strategy and 

 treatment are the same. 



Following are some of the means by which the vegetable- 

 gardener may hope to lessen or avert the losses from in- 

 sects and diseases: 

 . ■ 1. By means of rotation in crops and in methods of 

 tillage. The shorter the rotation, the less is the liability 

 to serious insect attacks. It is rare that insects and 

 diseases appear suddenly in great numbers. They increase 

 year by year, and in a favorable season prove very destruc- 

 tive. If the kinds of crops have been various, the prob- 

 ability is that they will not have gained a serious foot- 

 hold, and that they will be held in comparative subjec- 

 tion. It is essential that the crops of a rotation be of such 

 different kinds that the same kinds of insects or fungi will 

 not thrive on them. 



2. If the land becomes seriously infested with any one 



