30 Climate of the British Isles 



Argyll and Bute (extreme west), as well as some of the 

 counties situated in the Southern Uplands, growing no 

 wheat at all. According to W. Gr. Smith' "wheat ceases 

 to be a regular crop of the farm at an altitude where the 

 mean July temperature is below 56° F. [13'3° 0.] and 

 the rainfall exceeds 32 to 84 inches (about 800 to 850 mm.) 

 per annum." 



The total amount of wheat grown in Ireland is in- 

 significant, but the province of Leinster, containing the 

 driest part of the country and having the warmest 

 summers, possesses the largest acreage. 



It is thus seen very clearly that most of the British 

 wheat is grown in the regions of low rainfall and com- 

 paratively warm summers, while the regions of high 

 rainfall and the coolest summers grow no wheat at all. 



Barley, of which the total British acreage is now rather 

 below that of wheat, is not so dependent on 



*^j climatic conditions, but a large proportion is 



grown in the wheat-producing counties of 



England, though Wales and the east of Scotland have 



a good deal more barley than wheat, and no Scottish 



county shows absolutely none. 



Oats, the third great cereal crop, mature well in far 

 damper and cooler summers than either wheat or barley. 

 In some recent years the acreage in Great Britain has 

 been nearly double that of wheat, but in 1909, owing 

 to a considerable increase in the wheat area and a slight 

 decrease in the area under oats, the proportion was not 

 quite so high. The distribution of the crop is very 

 diiferent. While the eastern counties grow considerable 

 quantities of oats, the acreage is well below that of either 

 barley or wheat. In the south-west, on the other hand, 

 the acreage under oats approximately equals that under 

 wheat and barley together, while in the north-west it is 



1 W. G. Smith, 1904, p. 627. 



