174 Report or the Department of Botany of the 



Table III (concluded). 



NOTES ON PRECEDING TABLE. 



The bulk of the weed-seed impurities of commercial seeds 

 consists chiefly of well known established weeds, yet such com- 

 mercial seed is the natural channel for the introduction of other 

 weeds less well known in New York. This is especially true of 

 imported seed or seed from the western states. From a study of 

 the preceding table, and the work bearing directly upon the sub- 

 ject the following observations regarding some old and new weeds 

 are made: 



Dodder. — Both small-seeded and large-seeded dodder occurred 

 in samples of alfalfa and red clover. Thirteen per ct. of the alfalfa 

 samples were found to contain dodder seed varying in amounts 

 from a few seeds to a pound of alfalfa seed to 2 per ct. dodder 

 seed, as was found to be the case in one sample. In this it seemed 

 evident that this large amount of dodder seed had been intro- 



