317 



more upon the variety cultivated than upon either soil or climate. 

 The spring wheat of Dakota and ^linnesota produces as strong flour 

 as does grain from a sunnier climate. It is true that certain varieties 

 of very hard wheats only grow in hot, dry climates. Such is said to 

 be the' case with the best macaroni wheats. It is claimed that the 

 macaroni wheats of California are equal to the best of northern 

 Africa or of southern Europe and that the macaroni made from it in 

 San Francisco is equal to the best Italian. But while, as a whole, 

 the quantity of gluten and the strength of the flour is determined more 

 by the variety of wheat than by the climate or the soil, yet both of the 

 latter have their influence on chemical composition. Although direct 

 chemical evidence is lacking, derived from a large numl)er of chem- 

 ical analyses from samples chosen with this special object in view, 

 it is claimed that abundance of phosphates in the soil increases the 

 quantity of gluten in the crop. The millers of western New York 

 say that the flour has grown stronger with the increase in the use of 

 superphosphates in growing wheat in that region, and that the same 

 has often been stated as a fact in English experience. 



The particularly bright character of American grain, however, 

 depends upon the climate rather than upon the soil. The sunny 

 climate of the whole United States south and west of New England 

 is favorable for this, and from the time of the first settlement of 

 the colonies the bright color of American grain, as compared with 

 that of northern Europe, particularly that of Great Britain, has been 

 remarked. 



The table of distribution according to annual temperature (Tenth 

 Census, Cereals, Table XIX, p. 14) shows that the greatest produc- 

 tion is where the mean annual temperature is between 50° and 55°, 

 173,895,149 bushels, or 37.8 per cent, being grown in this belt, and 

 136,401,822, or 29.7 per cent, where the mean annual temperature is 

 between 45° and 50°. Adding these two, we see that 310,296,971 

 bushels, or 67.5 per cent, is grown where the mean annual tempera- 

 ture is between 45° and 55°. Considered in respect to the mid- 

 summer or July temperature (Table XX, p. 14), which has much to 

 do with the ripening of the gi^ain, our figures are of less interest in 

 this crop, because over considerable regions of the country the crop 

 is already ripe before July begins, notably in California ; but we 

 find that 223,852,371 bushels, or 48.7 per cent, grows where the mean 

 temperature of July is between 70° and 75°, and 178,530,037 bushels, 

 or 38.9 per cent, where the midsummer temperature is between 75° 

 and 80°, or an aggregate of 87.6 per cent wdiere the July temperature 

 is between 70° and 80° and 97.3 per cent where it is between 65° and 

 85°. AMiile the ideal climate for wheat is one of mild winters, and 

 some of the most noted wheat regions of the world are where snow 

 and frozen ground are unknown or very rare (as in Egypt, India, 

 and California), nevertheless most of the wheat of the world grows 

 in regions of cold winters. 



The table of distribution according to mean winter temperature 

 (Tenth Census, Cereals, Table XXI, p. 15) shows that in this country 

 46.6 per cent grows wdiere the mean January temperature is between 

 20° and 30°, 68.9 per cent where it is below "30°, and it is safe to say 

 that 70 per cent of the wheat crop of the country is grown where the 



