460 Minnesota Plant Life. 



of peat-bogs are the peat-mosses, the most abundant and in 

 some respects the most remarkable of all the mosses. A con- 

 siderable number of different species occur in Minnesota. 

 They are extremely spongy and contain a large amount of 

 water in special cells of their leaves and stems. Besides the 

 peat-mosses a number of other mosses will be found in peat- 

 bogs, with a variety of liverworts. Here, too, is the favorite 

 home of many sedges, such as the cotton-grasses, of many grasses 

 and lilies, of rushes and of orchids. Heaths are a marked fea- 

 ture of peat-bogs and almost all the Minnesota varieties are to 

 be looked for in such localities, where one finds the Labrador 

 tea, the Kahnias, the rosemarys, the cranberries, the snow- 

 berries, the leatherleafs and the bilberries. Mingled with them 

 are a number of other peat-bog-dwelling plants belonging 

 to various families. Here one will find the sundews and 

 pitcher-plants, the dogwoods, brambles and sweet-ferns, the 

 myrtle-leafed willow, the tag-alder and the crowberry. Espe- 

 cially distinctive of such areas are spruces and tamaracks and 

 these are the most characteristic trees of peat-bogs in the Min- 

 nesota region. They are often very much dwarfed by the 

 cold water and by the low percentages of mineral salts which 

 these waters contain. Especially when growing in the wet 

 region of the bog are the trees diminutive; and spruce trees 

 75 years old and but little over an inch and a half in diameter 

 have been found in Minnesota peat-bogs. 



It is probably on account of the low nitrogenous content of 

 the water that carnivorous plants, such as the pitcher-plant and 

 sundews, have developed particularly in peat-bogs. They are 

 able by their insect-catching habits to supply, from the bodies 

 of their victims, nitrogen to compensate for the scantiness of 

 this element in the soil. 



Most of the species in peat-bogs are perennial. On account 

 of the open, meadow-like character of typical peat-bogs the 

 snow accumulates in heavy sheets and this will perhaps account 

 to some extent for the prevalence of prostrate shrubs like the 

 heaths. No doubt also the prostrate habit is resultant from 

 the necessity for slow evaporation. Since the heaths do not 

 lift their leaves into the air on erect shoots so abundantly as 

 do other kinds of shrubs, they avoid that agitation by the wind 

 which would promote evaporation. 



