110 GARDENING FOR THE SOUTH. 



the destruction of a great many several weeks later, be- 

 cause of the rapid multiplication of the animals, as 

 already stated. The use of poisons like Paris green will 

 produce but little, if any, effect upon these insects, since 

 they get their food by inserting their sucking organs into 

 the tissues of the plants out of reach of the poison, which 

 is only on the surface. Spraying with kerosene emulsion 

 and enveloping the plant with gas will accomplish much, 

 how r ever, in the destruction of the lice. For the prepara- 

 tion of this emulsion see table opposite page 184. 



3. Insects which Bore into the Stem and Feed upon the ^Yoocl 

 of the Plant. — These insects must be circumvented by 

 placing on the body of the plant preparations which will 

 prohibit the deposit of eggs; or by washing the trunk 

 with poisons which will destroy the young grubs as they 

 cut into the bark. A good preparation is a glue contain- 

 ing Paris green. After the insect has entered the tree a 

 wire must be used to destroy it, or the place attacked 

 may be cut and the grub destroyed; but, of course, the 

 tree is considerably injured by such treatment, particu- 

 larly if the insect has penetrated to considerable depths. 



4. Insects which Attack the Roots. — The treatment of 

 plants which are subjected to the attacks of these animals 

 is almost hopeless because of the nature of the soil and 

 the danger of destroying the delicate roots by the use of 

 strong chemicals. The best method now known is crop 

 rotation, or the starving of the animals by the cultivation 

 of those plants known to be exempt from their attacks. 



5. Fungi Living on the Outside Surfaces of Plants. — These 

 comprise the mildews and moulds generally noticed on 

 the young, tender shoots and leaves of many plants when 

 they are in the condition for the favorable growth of 

 these diseases. The remedy is in the use of sulphur vapor. 



6. Fungi which Penetrate the Tissues. — These are the 

 rusts, smuts, spot-fungi, etc., found growing on the tender 



