76 IOWA ACADEMY OF SCIENCES. 



WOODY PLANTS OF WESTERN WISCONSIN, 



BY L. H. PAMJVIEL. 



This paper simply embodies the results of some observations made about 

 La Crosse, Wisconsin, from twenty to twenty-five miles northeast and south, 

 and the southwestern part of Minnesota in Houston and Fillmore counties. 

 The region is entirely in the driftless area.i This part of the State is lower 

 than the area lying to the northeast. Its most marked feature is the absence 

 of drift. This area (driftless) occupies about 12,000 square miles. So far as 

 the soil is concerned, it is not unlike that fouud in many other parts of the 

 State. Sandy soils abound as elsewhere in the State. In some cases the 

 topography is nearly flat, but generally it is hilly and in some cases slightly 

 rolling. The alluvial bottoms along the streams and creeks abound in as 

 rich a soil as is fouud anywhere in the State. Prairies are limited and of 

 small size, in some cases sandy with black, sandy depressions of better soil. 

 La Crosse Prairie, on which La Crosse is built, may be given as an illustra- 

 tion. Few trees abound except along its margins near the rivers. This 

 prairie is bounded by La Crosse river on the north, Mississippi river on the 

 west, and Mormon Cooley creek on the south. The regiou is abundantly 

 supplied with water, there being numerous small streams and springs, 

 which occur in almost every valley, besides there are streams of consider- 

 able size like Black, Root, Kickapoo and La Crosse rivers. 



The geological formation belongs to the lower Silurian which shows 

 abundant out-crops of potsdam sandstone everywhere. According to Moses 

 Strong,'- the maximum elevation of the hills at La Crosse is 470 feet above 

 the river. The hills are only 350 feet at Fountain City, 200 feet at Maiden 

 Rock and eighty feet at Bay City. The higher hills facing the Mississippi 

 river are covered with lower magnesium limestone, varying considerable in 

 thickness. The fact that the soils on the ridges, as well as the valleys, were 

 once thickly covered with timber, and is returning to that condition, when 

 allowed to do so, is largely due to the decomposition of the limestone 

 rock and the physical condition of the soil. This soil is not only fertile, 

 but retentive of moisture, which is an important feature in forest growth. 

 The alluvial soils, which are derived from the washing of the hills, have a 

 somewhat different growth than is found on the ridges and valleys, since 



iGeology of Wisconsin, Vol. I. p. 260-608. 

 2Geology of Wisconsin, Vol. IV, p. 39. 



