48 THE HUMAN SIDE OF PLANTS 



pany of bachelor's-buttons; and dandelions fre- 

 quently grow among turnips and radishes. These 

 clever habits allow many a plant that otherwise 

 would be destroyed as a useless weed to have a 

 permanent home and to bear fruit. 



Another example of the cleverness of plants in 

 protecting themselves is the growth of all kinds of 

 nuts on the trees. During the time of development 

 they are green, the colour of the foliage, and there- 

 fore hardly discernible; when, however, they are 

 ready to fall to the earth in order to start new 

 trees, they change to dark brown, the colour of the 

 ground on which they are soon to rest. The hazel- 

 nut is especially clever in its disguise, the nut being 

 enclosed in a leaf -like green bract, which by its 

 resemblance to the other leaves very effectually 

 hides the nut from view. The walnut has a hard 

 spongy covering filled with an acrid juice which is 

 exceedingly distasteful even after the fruit has 

 dropped to the ground. 



In waging war among themselves not always the 

 stronger plant is victorious; ofttimes, apparently, 

 the weaker uses ingenious methods and wins in the 

 struggle for existence. Especially is this true of 

 weak vines with delicate stems ; the common morn- 

 ing-glory, for example, climbs right over its more 

 gifted neighbours, reaching its ambitious flowers 



