PLANT STUDIES 



PART IV, STEMS 



The budding twigs spread out their fan 



To catch the breezy air ; 

 And I must think, do all I can, 



That there was pleasure there. 



— WOBDS WORTH. 



The service ordinary stems do for ground, is that which grows below it. 



plants is the production of leaves, roots, These underground stems are not pos- 



and the flowers which are most important sessed by all plants, for we have already 



to the plant, since they, in turn, produce seen that many plants are entirely killed 



the seeds. Stems are also the canals by cold weather. But some plants store 



which carry the material made by the up nourishment in a portion of the stem, 



leaves into every part of the plant and either partly or wholly covered by earth, 



bring up from the roots the nourishment so that they are able to live year in and 



gathered out of the earth. year out. A rootstock is a thickened 



The stems that we think most about stem which provides foods for its buds 

 live above ground. Many of them, when just as the thickened cotyledons did for 

 the winter comes, die down completely, the young embryo. The mint has a root- 

 and the particular plant of which they stock that creeps along underneath the 

 formed a part never appears again, ground, at intervals sending up stems 

 though others like it grow the next year to the air, which produce leaves and 

 from the seed. Such plants are herba- seeds and then in the fall die down. But 

 ceous, that is, live herbs, such as butter- the underground stem, the rootstock, 

 cups, anemones, columbines, and lark- lives on, ready to repeat the process of 

 spurs. Other stems, less soft and deli- producing a new plant the following 

 cate than those of herbs and able to live spring. Such plants are hard to get rid 

 from year to year without dying when of, those that grow "by the root," as it 

 winter comes belong to shrubs and trees, is said ; but we know it is by the stem 

 The hardy lilac and syringa have woody they grow since only stems produce buds 

 stems, while those of the oak and ash are and leaves, or in the case of the root- 

 still tougher and stronger. stock, scales which correspond to leaves. 



Stems are not all erect but hold them- If one cuts down the usual weed and 

 selves in different ways : The white destroys the root, the plant may be killed 

 clover creeps; peas, grapevines, and ivy completely. But cut through the stem 

 climb; and the morning glory twines, of mint or calamus and you have two 

 To suit its particular purpose the plant plants instead of one ; for each part of 

 modifies certain branches. Tendrils are the rootstock is able to produce roots and 

 slender branches which grow out from send up stems or leaves, 

 the stem until they reach something Some rootstocks are curiously marked, 

 about which to cling, then twist spirally, Solomon's seal is so called from the fact 

 so become shorter, and the vine is drawn that it bears on its surface scars that re- 

 nearer the support. The Virginia creep- semble the impression of a seal. Each 

 er has another plan by which it is enabled year at the end of the rootstock a bud is 

 to climb a wall or cliff. The ends of the formed which in the spring develops into 

 tendrils are flattened into disks which the plant above ground. In the fall this 

 adhere so closely to the smooth surface plant dies and breaks off from the root- 

 that the vine is able to cling to it and stock leaving a scar. Again a bud is 

 so ascend. formed on the rootstock at the end of the 



Another kind of stem important to year's growth, ready to develop the fol- 



plants, besides those that grow above lowing spring. So at regular intervals 



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