FLOWEKING PLANTS AND PEBNS 01 [NDIANA. 591 



the growth of the shoots of the following spring. At first the labor 

 involved in this method may be very great, but in a short time the 

 weeds will be found to be so reduced in numbers as to be of easy con- 

 trol. Each type of weed requires its particular treatment, and this can 

 only be given when the farmer knows, and knows thoroughly, some of 

 the fundamental laws governing plant growth and reproduction. 



The best efforts in cultivated areas will be of little avail if roadsides 

 and waste places are allowed to remain untouched. The manifold 

 methods of seed dispersion will be sufficient to insure the renewal of 

 the weed crop from these sources. A thriftless farmer may add im- 

 mensely to the labor of his neighbors who are using intelligent efforts 

 to rid themselves of weeds. Co-operation is the secret of success in 

 weed extermination, and in every movement to check the spread of 

 weeds as wide a co-operation as possible should be secured. A little 

 investigation of the monetary loss caused by the unchecked spread of 

 weeds ought to be enough to secure broadly concerted action on the 

 part of landowners in this beneficent work. 



Of the making of weed lists there is no end, and such weed lists 

 have a certain local value. No such list, however, can be of very gen- 

 eral application because the factors determining plant growth vary so 

 greatly in different localities. The weeds in Indiana which may per- 

 haps be considered the most annoying to the farmer will be found in- 

 cluded in the following lists. The relative rank as to badness will vary 

 in different localities, but all pamed are bad and should be persistently 

 destroyed. In all probability these species will never be completely 

 driven from our area, but their numbers may be so reduced by con- 

 certed, intelligent action that they will no longer demand so large a 

 measure of labor for holding in check nor involve such serious finan- 

 cial loss from year to year. In "Gleanings From Xature" (p. 251), 

 Prof. W: S. Blatchley gives the following list named, in his view, "in 

 the order of their injuriousness." 



Ragweed. Ambrosia artemiscefolia L. 

 Foxtail. Ixophorm glaucus (L. i Nash. 

 Ironweed. Vernonia fasciculata Michx. 

 Great ragweed. Ambrosia trip da L. 

 Pigweed. Amarantus rrfroflexus L. 

 Horseweed. Lepttton Canaden&e (L. I Britton. 

 Cocklebur. Xanthium Canadense Mill. 

 "White top. Erigeron annuns L. 

 Lamb's quarters. Chenopodium album L. 

 Common thistle. Carduut lanceolatus L. 

 Field sorrel. Rumex Aceimella L. 



