WEEDS OP THE FARM 263 



Study 37. Weeds of the Field 

 The program of work for this study will consist of a trip 

 about the fields containing both tilled and untilled crops, 

 examining all the common weeds occurring in each, and com- 

 paring them and writing their characters in a table prepared 

 with the following headings: 



1. Name (ask the instructor if you do not know it). 



2. Height (or length of stem, if horizontal, in inches). 



3. Growth-habit (erect, spreading, trailing, creeping, 

 climbing, twining, etc.). 



4. Root (form, depth and strength of attachment to soil) . 



5. Leaf (diagram, and state size, length and width inmm. ; 

 of a leaflet, if compound). 



6. Flower or flower-cluster (diagram). 

 Size. 



Form (diagram). 

 Mode of dispersal. 



Preferred situation. 



Name (of crop in which weed is found). 

 Stage (time elapsed since seeding). 

 Spacing (average interval between plants each 

 way as expressed in inches). 

 The record of this study will consist of: 



1. The above table complete for at least a dozen weeds. 



2. Lists of all weeds found in corn field, wheat field, etc., 

 arranged in what appears to be the order of their abundance 

 and harmfulness there. Note that not numerical abun- 

 dance, but bulk and aggressiveness are here intended. 



3. Comparative diagrams for half a dozen weeds, illus- 

 trating peculiarities of growth-habit, or mode of increase, or 

 mode of seed distribution, that make them factors in the 

 competition of the fields. 



4. A map of the farm, with the centers of possible dispersal 

 of seeds of noxious weeds marked in red upon it. 



Seeds. 



Crop. 



