BROOM-RAPE 599 



destroy it at once, and it should not be allowed to ripen its seed. 

 Attempts to get rid of the pest by watering with a 5 per cent, 

 solution of ferrous sulphate or by the application of various 

 manures are unsatisfactory. Sometimes it is possible to cut off 

 all the clover stems without destroying the crown of the plant 

 attacked, but for complete extermination the infected plants 

 should be dug-, out, carefully carried away, and burnt. It must 

 also be borne in mind that small pieces left on the field may 

 become attached to new plants, and the infection spread again. 



Flax-Dodder [Cuscuta Epilinwn Weihe) and Greater Dodder 

 (C europma L.) occurring upon hops, nettles, vetches, beans, 

 and other herbaceous plants, resemble clover-dodder in their 

 manner of growth and life-history. 



Other species of Dodder, such as C. racemosa Mart., C. 

 Gronovii Willd., and C. chilensis K., are introduced into Europe 

 with lucerne red clover and other leguminous seeds from North 

 and South America. Except in the warm southern climates, 

 they do little damage to the crops. 



OROBA.NCHACB.ffi — Broom-rape.— There are several species 

 of Broom-rapes or Robbers of Broom met with in this country. 

 Like the dodders they are all strictly parasitic, but attach them- 

 selves by means of haustoria to the roots of their hosts. The 

 larger broom-rape (Orobanche major L.) lives upon shrubby legu- 

 minous plants, especially broom and gorse ; the smaller broom-rape 

 (O minor Sutt.), however, is the farmer's special bane, as it feeds 

 upon and destroys red clover. The seeds are extremely small 

 and light, several hundred being produced from a single flower. 

 When shed from their capsules they are easily blown about. The 

 seedlings are thread-like, similar to those of dodder, but instead 

 of curving upwards they penetrate the soil, although they are 

 unable to obtain nourishment from it. It appears that only 

 special plants can afford nourishment to the broom-rapes. If a 

 seedling of the lesser broom-rape does not meet with a clover 

 plant in the soil, it soon dies. On contact with the roots of red 



