ro 



the center, showing that they are of great age. But few perennials 

 have persisted, the most notable of which is Brezveria Pickeringii, 

 growing in large tangled masses three to five feet (1-2 m.) across. 



Along the same railroad near Keithsburg, Andropogon sco partus 

 is the dominant species. Burning there has been less frequent, or 

 has not occurred for a longer time, since there are many plants of 

 Boutcloua hirsiita and some blue-grass. Aiitcniiaria frequently forms 

 mats on the ground and there are some patches of Helianthns occi- 

 dental is, which are so dense that almost all other plant growth is 

 excluded from them. Some other perennials in this habitat are 

 Ceanothus am eric anus, Tradcscautia reflc.va, Solidago nemoralis, 

 Desmodinin illinoensc, and Rudbeckia hirta, but the most abundant of 

 all is Bnphorhia coroUata. There are comparatively few interstitials. 



Along the Chicago and Northwestern railroad southwest of Dixon 

 the surface is thickly covered with cinders but there is little evidence 

 of burning. There is a good growth of Lcptoloma cognatuin, and a 

 few scattered plants of Paniciiin Scribneriaiium still persist. Bn- 

 plwrbia coroUata is abundant, and numerous patches of Bquisetiiin 

 hyeiiiale, var. iiitcnncditiin occur. Other secondai-y plants are 

 Chrysopsis z'illosa, Brauncria pallida, Heliaiithiis occidcntalis, and 

 Monarda punctata. 



Pasturing, if too close, results in the destruction of part of the 

 bunches and a consequent increase in the number of interstitials. If 

 continued too long, the sand may begin to blow, ruining the pasture 

 or possibly even the adjacent fields. The bunch-grasses seem to be 

 poorly adapted to grazing and they are soon dis])laced by blue-g"rass. 

 Some of the coarser species are avoided by stock, and persist for a 

 longer time. 



On a hillside pasture in the Hano\'er region Bragrostis pectinacea 

 is in most places the only bunch-grass remaining. Cyperus Scliwei- 

 nitzii is abundant and blue-grass is appearing in a few patches. The 

 secondary species include a large proportion of annuals, of which 

 Monarda punctata is especially abundant. This species with its ex- 

 ceedingly pungent foliage is not eaten by stock and seems to flourish 

 in pastures notwithstanding the tramping. It will be noted that many 

 of the species listed below have a similar protection against grazing 

 animals. The following species were observed. 



Grasses : 



Setaria glauca Bragrostis pectinacea 



Cenchrus carolinianus Poa pratensis 



Aristida tuberculosa Cyperus Schweinitcii 



