The Roots of the Wheat Plant. 183 



winter before it to mellow and crumble it, it should be more 

 carefully prepared, and if possible a more even and uniform depth 

 of sowing should be adopted. 



2. Acclimatization. — From what has been already advanced it 

 will be seen that although wheat is adapted in its varieties to 

 almost every degree of temperature, succeeding better in tempe- 

 rate than in tropical heat, it is yet derived from a wild grass 

 whose natural habitat may be said to be that of a warm climate. 

 Hence, then, the wheat-plant has great powers of adapting itself 

 to circumstances, and this is not only so as regards the world at 

 large, but we shall see, on inquiry, that even the slight inflexions 

 of difference presented in our own island, nay, even in the up- 

 lands and lowlands of a single county, have a decided influence 

 on the growth of the wheat-plant. 



If we review the geography of a central county of England, for 

 example, Gloucestershire, we shall see that it is divided into two 

 districts — hill and vale : the flat valley of the Severn, extending 

 from south to north for about 30 miles in length, and nearly 

 20 broad, has a range of hills on the eastern side, rising from 

 the vale with a steep escarpment, thus forming the Cotteswold 

 district, which presents variations in height to as much as 1,200 

 feet above the level of the sea. Now on these hills the prevail- 

 ing sorts of wheat will be the hardier red varieties, whilst in the 

 vale the finer white kinds are those planted on good, well- 

 drained land ; but in the stiff unmitigated lias clays the heavy, 

 woolly-eared winter wheat is much cultivated on account of its 

 enormous yield. 



In choosing wheat for seed, attention should always be paiil to 

 the circumstances of climate and soil. I have many times tried 

 to grow the spelt wheats from India, but have not succeeded in 

 ripening it, though at first it grows away freely and gives great 

 promise. Experiments now pending with yEr/ilops threaten 

 failure from the difficulty of ripening the seed ; but here, as I 

 have the wild grass to deal with, and my object is to change it in 

 form and habit, acclimatization will be an expected result of a 

 continuance of the experiments. 



Seed wheat should always be chosen from a poor soil for growth 

 on a richer one, and from a cold climate for cultivation in a 

 warmer : acting contrary to this rule often induces disease and a 

 shortness in the yield. In Gloucestershire the hill farmer chooses 

 seed from the exposed chalk wolds of Wilts, whilst the vale 

 farmer g^ts liis seed from the hills. But in the same manner as 

 spring wheat may be cultivated into a winter varietv, so may any 

 sort of wheat Ijccome ac( limatised by careful cultivation : this, 

 however, sometimes entails a slight change of form, and hence 

 have arisen tali and dwarf varieties, early and late forms, and 



