WEEDS OF SOUTHWESTERN WISCONSIN 



AM) 



SOUTHEASTERN MINNESOTA. 



A CONTRIBUTION TO THE LOCAL FLORA OF 

 LA CROSSE AND VICINITY. 



By L. H. Pammel, St.* Louis, Mo. 



The term " weed" is used somewhat loosely, and often plants 

 which are not troublesome are called weeds, and on the other hand 

 certain plants which are showy are not (among the laity, at 

 least), considered weeds, such as the common Corn Poppy, of Eu- 

 rope, Papaver rhceas. But any plant growing persistently where 

 it is not wanted may be looked upon as a weed. One of the best 

 definitions, and the one now generally accepted, is a "plant out 

 of place." This definition includes everything which can pos- 

 sibly be called a weed, whether showy or not. The greater num- 

 ber of weeds do not have showy flowers, a few exceptions are 

 the mustard, thistles, etc. 



PROLIFICACY OF WEEDS. 



The following figures are from Prof. W. R. Lazenby. (1) In 

 Wild Parsnips the number of seeds per plant was from 4,834 to 

 19,000. A rather large plant of Curled Dock, Rumex crispus, 

 36,000. Shepherd's Purse, Capsella bursa pastoris, 62,500 to 

 77,500. The Burdock, Arctium lappa, had, the second year of 

 its existence, 400,328. A single plant of Foxtail Grass, Setaria 



