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Handbook of Nature-Study 



THE MILKWEED 



Teacher's Story 



"Little weavers of the summer, with sunbeam shuttle bright, 

 And loom unseen by mortals, you are busy day and night, 

 Weaving fairy threads as filmy, and soft as cloud swans, seen 

 In broad blue sky-land rivers, above earth's fields of green." 



RAY LAURANCE. 



S there any other young plant that shows off its 

 baby-clothes as does the young milkweed! 

 When it comes up through the soil, each leaf is 

 folded lengthwise around the stem, flannel 

 side out, and it is entirely soft and white and 

 infantile. The most striking peculiarity of 

 the milkweed plant is its white juice, which is a 

 kind of rubber. Let a drop of it dry on the 

 back of the hand, and when we try to remove 

 it we find it quite elastic and possessed of all 

 of the qualities of crude rubber. At the first trial it seems quite impossi- 

 ble to tell from which part of the stem this white juice comes, but by 

 blotting the cut end once or twice, the hollow of the center of the stem is 

 seen to have around it a dark (green |ring, and outside this is a light green 

 ring. It is from the dark green ring encircling the stem cavity that the 

 milk exudes. This milk 

 is not the sap of the plant 

 any more than resin is the 

 sap of the pine; it is a 

 special secretion, and is 

 very acrid to the taste, 

 rendering milkweed dis- 

 gusting to grazing ani- 

 mals. If a milkweed 

 stem be broken or gashed, 

 this juice soon heals the 

 wound and keeps out 

 germs, and thus is of great 

 use to the plant, since 

 many insects feed upon it. 

 If cut across, every vein 

 in every leaf produces 

 "milk", and so does every 

 small flower pedicel. 

 When the "milk" is by 

 chance smeared on cloth 

 and allowed to dry, soap 

 and water will not remove 

 it, but it yields readily to 

 chloroform, which is a sol- 

 vent of rubber. 



The milkweed leaves 

 are in stately conventional 



Milkweed in blossom. 

 Photo by Verne Morton. 



