162 



GEOLOGY OF LA SALLE COUNTY. 



The one and one-half foot seam of coal at 200 feet 

 below surface is no doubt a tong-ue of the Streator bed, 

 No. 7 much thinned, as it is, at Wenona. The three 

 and a half feet bed is No. 2, thicker than at this place, 

 but about the same as at Wenona. The " hard white 

 rock below it, containing- the soft g-as-bearing- streak, 

 is the Trenton limestone, which is probably not less 

 than 200 feet thick at that place. Whether deeper 

 boring- would lead to the production of more gas is an 

 interesting- question. It would probably lead to flow- 

 ing- water, but at what depth is uncertain. 



WEEDS. 



In Part I the reader will find a short article on 

 "Weeds." We g-ive a list of what we consider the 

 troublesome weeds, that is those which the farmer 

 finds most difficult to g-et rid of. But some which are 

 new to the county are not mentioned. Among- these 

 are Salsola kali trag-us, the Russian thistle. We 

 believe that our soil, except where very sandy, is not 

 cong-enial to this plant, and that the dang-er of its 

 increasing- is small, but none the less should it be 

 watched. 



Iva Xanthifolia seems to be more at home, and 

 from its resemblance to several of our common weeds, 

 may spread widely before it is noticed. It should be 

 looked after. 



Atriplex patulum spreads slowly, but moves in 

 solid columns — it fills the g-round and should not be 

 suffered to make a lodg-ement. 



Acniaa tuberculata, formerly known as Montelia 

 tamariscina looks much like an Amaranth, and belong-s 

 to that family. It has spread along- the river and the 

 railways, and seems to be perfectly at home and gain- 

 ing- g-round very fast. 



Solanum Carolinense is evidently at home and 



