434 NEW JERSEY AGRICULTURAL COLLEGE 



ROOT PARASITES. 



Early in the season Hon. E. T. Gill, of Burlington county, sent 

 :3pecimens of a weed that was found in considerable abundance in 

 his clover field. It proved to be the clover broom-rape. This is a 

 flowering plant that is closel}'' related to the "Snap Dragon*' of the 

 garden, and the "Toad Flax," or " Butter and Eggs," a common 

 weed of the fields. The plant in question has a straoge habit of 

 fastening upon the roots of the clover plant and robbing it. The 

 broom-rape, in other words, is a parasite and shows its thieving 

 method of getting its living by being devoid of the ordinary green 

 so essential to plants that get their food out of the crude substance 

 of the earth and air. The broom-rape consists, therefore, of a ver}^ 

 limited root system, which is fastened to the roots of the clover, 

 known as its host plant, from which a comparatively stout, pale, 

 yellowish-brown stem arises for a foot to twenty inches, bearing 

 numerous sharp-pointed brown scales for leaves, of no great service 

 to the plant, and a spike of blossoms that are of good size, and in 

 color a mixture of yellow and blue. 



The photo-engraving (Plate VIIL) gives three of the broom-rape 

 plants from which the earth has been washed, and showing the pecu- 

 liar method of attachment to the clover roots. The one in the mid- 

 dle is the largest of the many sent by Mr. Gill, and shows how, by 

 toeing attached to one of the side roots of the clover, the parasite may 

 gain enough nourishment to make a large stem, shaped like an ox- 

 whip, with the large end attached to the host and bearing numerous 

 -flowers throughout the whole length of the portion extending above 

 ground. Clover that is thus attacked cannot make a satisfactory 

 growth, and from the subterranean nature of the pest during its 

 -early growth, any remedy is not easily^applied. 



In the present case it seems as if the seed of the broom-rape came 

 Into the soil along with that of the clover, but as all of the supply 

 ^of seed had been sown, there was no opportunity upon the part of 

 the Experiment Station to make an examination. The seed of this 

 broom-rape ( Orobanche minor J. E. S. ) , as with all the others, is very 

 small and could pass as "dust" with the clover seed, and therefore 

 is neither easily detected nor knowingly removed. If one was sus- 

 picious of the presence of this enemy, the clover seed might be 

 especially cleaned, and even soaked in water, to remove the small 

 foroom-rape seed. 



