170 PASTORAL AND" AGRICULTURAL BOTANY 



The average yield of barley in the United States for the ten year period, 

 1900 to 1909, was 25.7 bushels per acre. 



Rotations. Great care should be exercised in the rotation of barley 

 with other crops. Where barley replaces wheat in the rotation, the se- 

 quence of crops may be maize, barley and oats, each one year, or timothy 

 and clover, one or more years. The land has thus had surface tillage 

 the previous year and may have been manured. In some regions, 

 barley replaces oats, when the rotation becomes maize, barley and wheat, 

 each one year, followed with clover, or clover and timothy, one or two years. 



Rye (Secale cereale). The wild progenitor of the cultivated species is 

 looked upon by botanists as 5. anatolicum, one of the subspecies of S. 

 montanum, which extends from Spain and Morocco' to central Asia. The 

 wild species is a perennial, but the cultivated form is an annual. The root 

 system is a whorl of four primary roots, which extend into the soil to a 

 depth of four to five feet. The stems of rye with five to six, rarely four- 

 to seven-jointed are tougher, slenderer and larger than those of barley, 

 oats and wheat. The rye inflorescence is a spike of spikelets. Each 

 spikelet consists of three flowers, with the two lateral flowers perfect and 

 maturing grains, while the middle floret is abortive. The glumes are 

 narrow. The lemma is broad-keeled and bears a long terminal awn. 

 The palet is thin, blunt and two-keeled. The lodicules are small and 

 membranous. Three stamens are present in each perfect flower and a 

 single pistil with two feathery styles. Rye is commonly cross-fertilized 

 and in this respect is like maize, but unlike wheat, oats and barley. The 

 mature grain is free from the lemma and palet. It is long, narrow and 

 usually darker in color than wheat. 



The structure of the rye caryopsis is like that of wheat, with somewhat 

 similar layers of cell. Rye protein usually forms 6 to 12 per cent, of the 

 grain. Gluten is present in the protein, hence, rye can be made into 

 porous bread. 



Rye is adapted to a colder, drier climate than wheat. It does well on 

 poor, and sandy soils. Rye is fed to stock mixed with barley, maize, or 

 oats. 1 he straw is used for stable bedding, as a stuffing, and in the manu- 

 facture of paper, hats and other articles of straw. 



Cultivation. Spring rye is sometimes grown in the northern states, 

 but it should give way to winter rye, where that grain crop will survive. 

 About 96 per cent, of the world's rye is produced and consumed in Europe 

 where in such states, as Germany, Holland, Russia, Belgium, Austria and 



