LESSONS 0:S POTATOES EOR RURAL SCHOOLS. 19 



3. Types of cultivators: Weeder, disk cultivator, corn cultivator, 

 two-horse cultivator for large fields. 

 Cautions : 



1. Careless tillage may work great injury upon the crop, as potato 

 plants are more tender than we^ds. 



2. In using weeder or tooth harrow great care must be taken to pre- 

 vent the teeth from injuring the sprouts. 



3. In later growth the roots are in danger from too deep or too 

 close cultivation. The gi'eatest development of the roots in the 

 plowed area is from 5 to 10 inches below the surface. 



4. The danger of injury to the potato plant is greatest at blossom- 

 ing time, when the exhausting effects of blossoming and forming 

 tubers at the same time are very heavy. 



Practical exercises. — This lesson should essentially be a guide to 

 proper practice in potato cultivation. Many of the pupils will have 

 potatoes as a home project, others will assist in the home work on 

 the farm where potatoes are raised. The principles laid down in this 

 lesson should be put into careful practice in either case. 



A field trip to a potato farm would be valuable to the class. If 

 the projects are under the supervision of the school, the teacher 

 should try to visit each home as soon as possible to observe the 

 progress of the projects. If the teacher is working in cooperation 

 with the county or State club leader, it will be especially helpful to 

 make these visits at the same time the official representative makes 

 his visits to the work. In all cases this cooperation should strengthen 

 the school work if it is well carried out. 



Correlations. — The written reports, summaries, and costs of pro- 

 duction as completed in the project work will furnish ample correla- 

 tions in language and arithmetic. In case there is no project, the 

 same reports on the work of the j^upil on the home farm will furnish 



the same material. 



LESSON XI. 



Subject. — Potato-crop pests — Insects and diseases, how to combat 

 them. 



Prohlem. — To learn to identify the chief potato insect pests and 

 diseases and to discover proper methods of control. 



Sources of information. — Farmers' Bulletins 544, 557, and 868; 

 bulletins from State college of agriculture. 



Illustrative material. — S]3raying charts. Illustrations of spraying 

 apparatus. Samples of sprayers may often be borrowed from a 

 farmer in the district or loaned by the local dealer. Samples of 

 fungicides and insecticides. Illustrations or exhibits of the pests to 

 be controlled. Samples of potato plants affected with the common 

 fungus diseases may be brought to class for a study of the charac- 

 teristics of the disease. 



