CH. IV] 



Loess Soils 



55 



mingled with calcareous debris but without the large 

 amounts of organic matter of the black soils. These 

 give the deep rich soils found in Eastern Nebraska, Iowa 

 and parts of the Mississippi valley. All these areas are 

 characterised by cold clear winters and hot dry summers. 

 In the aggregate the rainfall may be sufficient but its 

 distribution is not always favourable to maximum crop 



Fig. 14. Alkali spot, Fremont, Nebraska. 



production. These areas are in the main treeless (see 

 Fig. 20). 



Coming still further east into the regions of wood 

 and forest where the climatic conditions approximate 

 more closely to our own, the soils also resemble ours in 

 England. 



A wholly different type of soil, known as the Tundra, 

 is found in the far north in the barren lands. It is black 



