FIELD CROPS. 587 



By the time that 40 per cent of the vegetable matter was formed GO 

 per cent of the total mineral matter and 53 per cent of the nitrogen 

 required by mature plants had been taken from the soil. At the period 

 of full bloom 88 per cent of the mineral matter and 80 j^er cent of the 

 nitrogen had been taken up by the crop. The period of growth and 

 maturity of the crop is ordinarily from 65 to 70 days after seeding. 



"From 70 to 90 per cent of the principal elements of plant food are taken from 

 the soil during the first 45 or 50 days. In order to furuisli this plant food in so short 

 a time the soil must be in the very best condition as to fertility." 



"The best flax soils are those that contain about 25 per cent of 

 medium sand, 20 to 25 per cent of fine and very fine sand, 35 to 40 per 

 cent of silt, and about 12 per cent of clay." This soil should also con- 

 tain from 15 to 20 per cent of available water. 



When tiax is cut in early bloom and cured it makes excellent hay. 

 The seed contains on an average about 35 per cent of oil, of which 7 to 

 8.5 per cent remains in the cake in the old process of extraction. 



In his summary the author states that flax does not remove an exces- 

 sive amount of fertility from the soil; that it possesses but little power 

 of obtaining its food from the soil; that home-grown seed is equally as 

 rich in stored up plant food as imported; that when flax is cut "on the 

 green side of bloom," and before seed development, and cured as hay, 

 it makes a valuable fodder; and that a yield of 15 bu. per acre will 

 produce about 270 to 280 lbs. of crude oil by pressure process. 



Forage crops, J. F. Hickman {Ohio Sta. BuL 70, pp. 81-107, pi. 4). — 

 In this bulletin are given the general results of experiments with forage 

 crops at the station since 1888, including methods of soil preparation, 

 quantity of seed used, manner of growth, length of season required, 

 and other data. The author recommends the following: Alfalfa for 

 lands having open or porous subsoils, cowpeas only for green manuring 

 on impoverished land, soja bean for forage and green manuring, Canada 

 peas and oats for forage, Indian corn as the foremost forage crop grown 

 in Ohio, Hungarian and German millets for catch crops when the hay 

 crop is short, and rape for forage. The hairy vetch has not been suf- 

 ficiently tested. Crimson clover is regarded as of doubtful value. The 

 flat pea, spring vetch, sweet clover, Brazilian flour corn, Kafir corn, 

 millo maize, Jerusalem corn, teosinte, Japanese and Russian millets, 

 sachaline, and spurry are not considered of sufficient value in Ohio to 

 justify their recommendation. 



Forage plants {Rhode Island Sta. Rpt, 1895, pp. 316-319). — Repeated 

 sowings of alfalfa have been made at the station, thus far without suc- 

 cess. Early maturing varieties of cowpeas have been sown and have 

 made a good growth, producing pods containing apparently mature 

 seeds which will be planted another season. Crimson clover has proven 

 satisfactory as a catch crop and for green manuring, but it must be 

 sown annually as it will seldom live through the winter. Egyptian 

 lentil was grown and is considered of little value as a grain crop as 



