ON WINTER RHUBARB 



ters are not too severe; and in some regions it is 

 so abundant as to be considered a weed, notwith- 

 standing the beauty of its flower. 



The genus Passiflora, to which the Passion 

 Flowers belong, is made up largely of vines and 

 shrubs, but there are a few members that grow to 

 the size of trees. 



The best flowering varieties are strictly trop- 

 ical, and do not thrive in the northern climates. 

 But, on the other hand, the species that bear the 

 larger and more edible fruits are relatively hardy. 

 Doubtless there is a casual relation between these 

 facts. Possibly the tropical species do not find it 

 difficult to propagate their kind, and have not 

 found it necessary to develop succulent fruits. In 

 any event, it is fortunate from the standpoint of 

 the plant developer of the temperate zones that 

 the fruit-bearing members of this particular tribe 

 are the ones that are hardy enough for introduc- 

 tion in our climate. 



In point of fact, the common species of the 

 Northeastern United States, locally known as the 

 Maypop, is so thrifty a plant that it becomes a very 

 troublesome weed. 



It spreads in all directions by its underground 

 root stalks, and it roots very deeply. It is almost 

 as difficult to eradicate as the perennial morning- 

 glory. Deep plowing of the soil is about the only 



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