Dr. H. P. Walcott tells the Massachusetts Horticultural Society : The insect enemies of the chrysanthemum are the green aphis through the season, the black aphis later, the grasshopper and a root louse. The aphides can be destroyed with tobacco water; the grasshoppers must be picked off by the hand, but no remedy is known for the root louse. The formation of the plants is effected by pinching; but to obtain perfection of flower, the Japanese should not be pinched more than once, or the large flowered more than twice, while the pompons may be pinched with safety to any extent up to the middle of August.