Vegetable Gardening 355 



able. Alfalfa turned under in this way is equivalent to 

 15 to 20 tons of manure. The seed potato, whether 

 quarters or whole potatoes are used, should be deeply 

 covered, as the tuber is formed on stems springing from 

 the seed potato. Hence, if the potato is planted shallow, 

 many of the potatoes in the crop will be so near the 



Fig 223. Germination and growth of corn at 55, 70 and 85 degrees F. 8 days after 

 planting. After Prof. J. A. Jeffery, Michigan Agricultural College. 



surface that they will sun scald. (See Fig. 222.) Potatoes 

 run out if not selected. At harvest time the potato digger 

 should be followed and seed saved from hills producing a 

 moderate number of good-sized, smooth potatoes. 



522. Frost and Rainfall Records. Write to the Weather 

 Bureau, U. S. Department of Agriculture, for full information as 

 to rainfall records and frost records by months made at the Observ- 

 atory Station nearest you. Ascertain what month in the year 

 has the heaviest average rainfall and what month the lowest. 



523. Test Soil Temperatures in your garden (see 1f 94). 

 With a dairy thermometer note the temperatures at the surface 

 and 3 inches below the surface once a week. Compare these with 

 the germination temperatures given in ^ 26. 



