446 STATE BOARD OF AGRICULTURE. 



of 500 lbs. per acre is the most satisfactory. A ton of this fertilizer is 

 made by mixing: 



193 lbs. nitrate of soda containing 15.5% nitrogen. 

 357 lbs, dried blood containing 14% nitrogen. 

 1,000 lbs. phosphoric acid containing 14% nitrogen. 

 450 lbs. sulphate of potash containing 48% nitrogen. 



2,000 lbs. "home mixed" potato fertilizer. 



It should not be overlooked that the value of a chemical fertilizer de- 

 pends largely upon the physical condition of the soil, the moisture con- 

 tent as well as proper drainage and cultivation. Even very heavy ap- 

 plications of fertilizers will not make up for the lack of any of these 

 conditions nor will the use of any kind of chemical fertilizer take the 

 place of the humus or decayed organic matter in the soil. 



PLANTING. 



Where the planting is done by hand, furrows may be opened with 

 team and one horse plow and if any chemical fertilizer is to be used it 

 can be spread in the furrow by hand. On light or loose soils it is de- 

 sirable to plant the seed about four to six inches deep. If shallow 

 planted some of the potatoes will become exposed and sun burn. The 

 seed pieces are dropped the distance desired, covered with a hoe, and the 

 whole field smoothed over with a harrow. 



It would be profitable to use machine planters upon large acreages 

 (over ten acres) and with these a fertilizer attachment is often used to 

 distribute the fertilizer. If the planter is not equipped with such an 

 attachment the fertilizer may be drilled in with an ordinary drill before 

 the field is planted, or can be spread by hand. 



The distance for planting depends upon the fertility of the soil, but 

 rows three feet apart and from 18 to 24 inches in the row has given good 

 results on an average soil. With intensive cultivation and a rich soil, 

 they may be planted as close as one foot in the rows. 



CULTIVATION. 



Frequent cultivation will greatly help to produce a good crop and 

 keep the field free from weeds. A spike tooth harrow is usually used 

 once or twice before the plants come up and again just as they appear. 

 A weeder is often used at this time and about once a week afterward 

 until the plants are several inches high. During this time it may be 

 advisable to go over the field once or twice with a cultivator. After the 

 plants are five or six inches high cultivate about once a week or every 

 ten days until there is danger of injury to the vines. 



SPRAYING. 



Potato plants are sprayed with Boi'deaux mixture (0 pounds of cojiper 

 sulphate, 5 poimds of stone lime and 50 gallons of water) to protect 

 them from blight and rot {Phijtophthora infestaus) and with ])oison 

 (V2 pound of paris green or 2 or 3 pounds of arsenate of lead added to 



