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Lower Wabash Valley 



This is a narrow strip of alluvial land on the east side of the Wabash 

 River from Parke County southward to the Ohio River and thence up the 

 Ohio River to Little Pigeon Creek in Warrick County. To it belong also 

 the short alluvial extensions of the White and Patoka Rivers. The whole 

 area is usually inundated each year at flood stage. Among the trees re- 

 stricted to these lowlands are Acer rubrum var. Drummondii, Carya Pecan 

 (with few exceptions), Celtis laevigata (with few exceptions), Forestiera 

 acuminata (with one exception), Gleditsia aquatica, Gleditsia texana, 

 Taxodium distichum, and Quercus lyrata (one exception). Other plants 

 are Aristolochia tomentosa, Echinodorus radicans, Hottonia inflata, Lep- 

 tochloa panicoides, Ludwigia glandulosa, Spigelia marilandica, Trache- 

 lospermum difforme, and Vitis palmata. All these species belong to the 

 flora of the Mississippi Valley and find their northeastern limit in this area. 



U n glaciated area 



This area may be divided into eastern and western parts. The western 

 part is included by Malott in the Wabash Lowland and is bounded on the 

 east by Anderson Creek to St. Meinrad and then extends northwestward 

 to the glacial boundary. The eastern half of this part is hilly and wooded 

 mostly with oaks. The western part has gently sloping or low hills and is 

 wooded on the high ground with beech, tulip, and sugar maple and in 

 the lowland with oak, hickory, elm, and sweet gum. I do not regard this 

 as a botanical area but only a part of a region where some southern 

 plants reach the northern limit of their distribution. In it, however, we 

 have Dicliptera brachiata and Crotonopsis elliptica that have not been 

 found outside of it. 



The eastern part of the unglaciated area is mostly hilly and broken, 

 being divided by the broad valley of White River. I think a good com- 

 mon name for it would be the "Chestnut Oak Upland" area, because this 

 species of oak crowns the crests of all of the high ridges of the area and 

 these ridges are popularly known as "chestnut oak ridges" or "knobs." 

 Malott divides the area into three parts. The most eastern he calls the 

 Norman Uplift, the middle the Mitchell Plain, and the western the Craw- 

 ford Upland. With the exception of one small restricted area I think 

 these uplands can be considered as one botanical unit. Pinus virginiana, 

 Virginia pine, crowns the crests of the highest ridges in Floyd County, 

 the western part of Clark County, a fragment of the southwestern part 

 of Scott County, and a few places on the southeast boundary of Wash- 

 ington County. The total area of pine is quite small and might well be 

 considered a separate botanical area if there were one more species pecul- 

 iar to it. 



Within the chestnut oak area many plants reach their northern limit. 

 Some, such as Bumelia lycioides, Oxydendrum arboreum, Ligusticum 

 canadense, Eragrostis capillaris, and Aconitum uncinatum, have merely 

 crossed the Ohio River. Others such as Smilax Bona-nox, Gentiana villosa, 

 Melothria pendula, Kalmia Mifolia, Galactia volubilis, and Cirsium vir- 

 ginianum have penetrated 5 to 25 miles. Others such as Quercus montanu 



