BENEFICIAL EFFECT OF PEAT. 



31 



nize soil acidity as a fundamental requirement of these plants. It 

 was perhaps natural to give the blueberry the same garden culture 

 that when applied to other bush fruits has resulted in their distinct 

 improvement. But the ordinary garden operations tend to make even 

 an acid soil neutral or alkaline, and in such a soil the blueberry does 

 not thrive. 



The death and decay of blueberry roots, with which the injurious 

 effect of alkaline soils is associated, are discussed on pages 64 and 05. 



(7) The favorite type of acid soil for the swamp blueberry is peat. 



Although the swamp blueberrj^ sometimes grows on upland soils 

 its typical habitat, as its name implies, is in swamps or bogs. The 

 cranberry, it is well 

 known, is cultivated al- 

 most exclusively in bogs. 

 In clearing bog land pre- 

 paratory to the planting 

 of cranberries one of the 

 necessary precautions is to 

 remove all roots of the 

 SAvaniiD blueberry. If the 

 roots are allowed to re- 

 nuiin in the ground, they 

 send u]) vigorous shoots, 

 and these, unless pulled, 

 develop into robust plants 

 which occupy the ground 

 to the great injury of 

 the cranberries. Large, 

 healthy, and productive 

 bushes of the swamp blue- 

 berry are frequent, almost 

 characteristic, inhabitants 

 of the uncultivated bor- 

 ders of cranberrv boo:s. 



Peat bogs, in the con- 

 ception of geologists, are 

 incipient coal beds. The 

 transformation of peat 

 into coal occupies very 

 long periods, perhaps some 

 uiillions of years. Peat is made np chiefly of vegetable matter, 

 the dead leaves, stems, and roots, of bog plants which are only 

 partly decayed. Their full decay is prevented primarily by 

 the presence of w^ater, which keeps away the air. The bacteria, 



193 



Fig. 10. — Blueberry seedling fed with acid nutrient 

 solution. ( Natural size. I 



