Care of the Growing Crop 163 



As a general rule the first cultivation after planting is 

 made as deep and as close to the seed as possible, because 

 the potato roots have not started far yet and are safe from 

 injury. The soil settles together so quickly that it should 

 be kept mellow in this way as long as possible. Sometimes 

 a second deep cultivation may be gi\en. Later cultiva- 

 tions after the roots start are made with the teeth working as 

 shallow as they can be made to work, so as to form a mellow 

 soil mulch. This depth will vary in different soils from one 

 to three inches. jNIeasurement will show that cultivator 

 teeth often work much deeper than the grower is aware. 

 As the tops begin to grow and form a mass, the cultivator 

 teeth can be narrowed. Weeds start less in the shade of 

 the tops and evaporation becomes less, partly on account 

 of the shade and partly because surface roots form to use 

 the moisture. Wide, deep teeth are manufactured to 

 cut the roots of perennial weeds like the Canada thistle. 

 Such teeth may often be substituted in part for the com- 

 mon teeth. Cultivators are made for one, two, three or 

 four horses, with wheels and without, and for the driver 

 to walk or ride. One-horse walking cultivators, common 

 in the East and South, have great disadvantages. Even 

 when fitted with wheels in front to regulate the depth, the 

 teeth cut much deeper in some soils than in others. The 

 machine is too light to hold in the soil in stony ground. 

 Masses of weed roots, like those of quack- or witch-grass, 

 clog the teeth and cause the teeth to rise out of the soil at 

 the very places where the best work is needed. Wheel 

 cultivators enable one to regulate the depth of working to 

 better advantage. The weight of the wheel cultivators, 

 with that of the driver, holds the teetli into the ground 

 among stones and weeds. The wheels prevent the teeth 

 from cutting too deeply in mellow places free from weeds. 



