Wheeler : flora of southeastern Minnesota. 359 



Creek valleys. — The valleys of the creeks present an entirely 

 different aspect from the river valley. The creeks have their 

 own well-defined channels to which they hold almost the year 

 round. High waters never last for any great period of time. 

 Those which are caused by the melting of the snows in the 

 spring generally last from about noon to sun-down while those 

 which are supplied by the heavy June showers generally rise 

 and fall during the night or very early morning. The damage 

 done to vegetation is almost restricted to the floods of the sum- 

 mer months. They come in the season of most rapid growth 

 and destroy a large part of the season's growth with which they 

 come in contact. The areas inundated by these floods are never 

 very extensive compared to those along the river. At most 

 points along the valleys the gradual rise of the land from the 

 creeks to the bluffs is sufficient to prevent the formation of 

 ponds and lakes by the rise of the water. The alluvial soils 

 deposited on the flats do not dry up until late in the summer and 

 so have very little growth besides coarse weeds. They are 

 often cultivated but there is always the danger of the crops 

 being destroyed by high water. Most of the best cultivated 

 fields in the valleys are on the table lands adjacent to the foot 

 of the bluffs. They are generally fertile, are protected from 

 high water and hard winds and are not in a position to wash to 

 any great extent. The steep banks on the north edges of the 

 table lands are generally wooded and bear the richest and 

 greatest variety of plants that can be found anywhere in this 

 •egion. The table lands are often very sharply marked off 

 :rom the creek bottoms and steep bluffs. Towards the heads of 

 he creeks the table lands disappear and there is a gradual rise 

 :rom the creeks to the bluffs. 



The water vegetation of the creek valleys is almost entirely 

 imited to the cold water plants of the springs and small streams. 

 There are very few ponds or marshes to contain still water 

 orms. 



The vegetation of the land may be divided into that of the 

 vet meadow, moist woods and mesophytic field. The wet mea- 

 low is about on a level with the banks of the creeks. It never 

 )ecomes very dry and on the lower places shows some of the 

 ;haracters of a marsh. The vegetation of the moist woods 

 s well shown on the wooded banks bordering the table lands. 

 Moist woods often cover some of the protected table lands and 



