536 



AMERICAN lORESTRY 



In plants of the cow-vetch order, the paired tendrils 

 are found at the terminus of any of the leaf-stalks; they 

 are fine and hair-like, but allow of the plant being a 

 most successful climber. Our common ground-nut is an 

 excellent example of a species that climbs to a height of 

 several feet with no developed structure to assist it. Wild 

 beans and hog peanuts are in the same case and we 

 find an equally good example in our bitter-sweet, a 

 climbing vine of great beauty, often seen running over 

 stone walls or old wooden rail fences. In the woods it 

 may sometimes take to a tree, climbing to a height of 

 some fifteen or twenty feet or more. In these eflforts 

 its stem becomes much twisted, causing its exquisite 

 fruit or flowers to assume regular positions with re- 

 spect to the stem a fact still more apparent in the pale 

 green ovate leaves which come out alternately or in 

 ranks, as it were, as the vine twists about its support. 



The peculiarities of wild grape vines have already been 

 alluded to elsewhere, while an additional character will 

 be mentioned here, one that must not be overlooked. 



LEAVES OF THE WILD GR.APE-VINE 



Fig. 7 All the parts here shown are from the same vine, and 

 the variations are apparent. Note the black aphids on the shoot 

 partly hidden by the incised leaf to the left. Collected and 

 photographed by the author. Much reduced. _ 



better hops ; the garden vines, as peas, beans and many 

 others, to produce vegetables of greater size and richer 

 in food qualities; for shade, bigger leaves, and power 

 to extend over greater surfaces; for beautiful and 

 curious flowers ; to enhance the characters for medicinal 

 products, to insure greater quantities and strength ; lor 

 products used in the arts and industries, various im- 

 provements in them, and so on. 

 There are various means inherent in any particular 

 vine or climber that ensures its being able to climb or 

 to creep. This may be done by sheer extension of 

 growth, the plant simply rambling over anything and 

 everything that chances to be in its way as it grows. In 

 others, as in tear-thumb, the four-angled, reclining stems 

 beset with fine, sharp prickles (at the angles only), 

 admits of its stems hanging onto, more or less tenacious- 

 ly, any ordinary thing it comes in contact with as it 

 extends through growth. 



Some plants, as in the strawberry group, possess 

 runners from which other plants are produced ; but 

 these runners must not be confused with such struc- 

 tures as allow other plants to creep or climb ; the func- 

 tion in either case is entirely different. 



It is a well-known fact that many plants climb by 

 tendrils curious little twisted affairs developed on the 

 stems and on other parts of the plant. These vary 

 greatly in form and structure. Some are extremely 

 delicate and weak ; others are wiry and very strong, as 

 in the grape-vine series; some develop little terminal 

 suckers, which, sticking onto anything in the vine's line 

 ot growth, hold on with remarkable tenacity. 



BUNCH OF UNRIPE WILD GRAPES 



Fig. 8 This specimen is from a vine growing in the woods 

 near Washington, D. C. Collected and photographed by the 

 author. Slightly reduced. 



