FIELD ROOT CROPS. 123 



cover with an addition of three inches of straw and 



twelve inches of earth. In order to get sufficient 



mould it is advisable to plow around the pits a 



number of furrows not exceeding nine inches in 



depth, as the siu-face soil which is composed of 



vegetable matter is more impervious to frost than 



clay. To make provision against excessive frost it 



is advisable to cover pits, the last of December, with 



stable manure to the depth of about ten inches. To 



ventilate a pit set three-inch drain tiles on top, with 



one end resting on the roots. Place about eight 



feet apart near the bottom of the pit, two-inch tiles, 



so as to cause a draught. Fill the tiles with straw 



in December. 



For field culture the white intermediate carrot Varieties, Cul- 

 tivation and 

 is unquestionably the most profitable variety for the Harvesting of 



farmer to grow for feeding purposes. The nutritive ^"° ^' 



value is equal to any of the white varieties, and it is 



much more easily harv^ested than the others. Under 



favorable conditions this carrot will yield from 



twenty-five to thirty tons per acre. The cultivation 



of carrots is similar to that for mangel-wurzels and 



sugar-beets, with the exception of thinning. The 



carrot plants should be from eight to ten inches 



apart in the row. The time to harvest is the last 



week in October. In harv^esting, the tops can be 



readily taken off with an ordinar\^ hoe, while the 



roots are still in the ground. Then, w4th an iron 



plow without the mould-board, or a subsoil plow 



(see III. g), the roots can be turned out. The plow 



should be run only sufficiently deep that the share 



will cut the points off the roots. This work may 



be done first and topping done afterwards with a 



knife. A very little frost will injure them after 



being pulled, so that it will be necessary to cover 



them at night if there is any danger of frost. Car- 



