From Blue to Purple 



covered with minute hooked bristles, the lower edge of pod 



scalloped ; almost seated in calyx. 

 Preferred Habitat— "Wiv^^Xs,, woods, river banks, bogs. 

 Flowering &ajo«— July — September. 

 Distribution — ^New Brunswick to Northwest Territory, south to 



North Carolina, westward to Indian Territory and Dakota. 



As one travels hundreds or even thousands of miles in a 

 comfortable railway carriage and sees the same flowers growing 

 throughout the length and breadth of the area, one cannot but 

 wonder how ever the plants manage to make the journey. We 

 know some creep along the ground, or under it, a tortoise pace, but 

 a winning one; that some send their offspring flying away from 

 home, like dandelions and thistles; and many others with wings 

 and darts are blown by the wind. Berries have their seeds dropped 

 afar by birds. Aquatic plants and those that grow beside running 

 water travel by river and flood. European species reach our shores 

 among the ballast. Darwin raised over sixty wild plants from 

 seed carried in a pellet of mud taken from the leg of a partridge. 

 So on and so on. The imagination delights to picture these floral 

 vagabonds, each with its own clever method of getting a fresh 

 start in the world. But by none of these methods just mentioned 

 do the tick-trefoils spread abroad. Theirs is indeed a by hook 

 or by crook system. The scalloped^ jointed pod, where the seeds 

 lie concealed, has minute crooked bristles, which catch in the 

 clothing of man or beast, so that every herd of sheep, every dog, 

 every man, woman, or child who passes through a patch of tre^ 

 foils gives them a lift. After a walk through the woods and lanes 

 of late summer and autumn, one's clothes reveal scores of tramps 

 that have stolen a ride in the hope of being picked off and dropped 

 amid better conditions in which to rear a family. 



Only the largest bees can easily "explode" the showy tick-|'' 

 trefoil. A bumblebee alights upon a flower, thrusts his headl 

 under the base of the standard petal, and forces apart the wing\ 

 petals with his legs, in order to dislodge them from the standard. 

 This motion causes the keel, also connected with the standard, to 

 snap down violently, thus releasing the column within and send- 

 ing upward an explosion of pollen on the under surface of the 

 bee. Here we see the wing petals acting as triggers to discharge 

 the flower. Depress them and up flies the fertilizing dust — once. 

 The little gun will not "go off" twice. No nectar rewards the 

 visitor, which usually is a pollen-collecting bee. The highly in- 

 telligent and important bumblebee has the advantage over his 

 smaller kin in being able to discharge the pollen from both large 

 and smaller flowers. 



The Naked-flowered Tick-trefoil (A/, nudiflora or D. nudi- 

 forum of Gray) lifts narrow, few-flowered panicles of rose- 



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