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GARDENERS' CHRONICLE 



What Is a Plant? 



WILLARD N. CLUTE 



IT is a good deal easier to define a plant in general terms 

 than it is to get down to jxirticulars. It is, of course, 

 recogiiized by eveiybody that plants form one of the 

 two great divisions of living things and that animals form 

 the other, but the difficulty occurs when one begins to lay 

 down rules that will absolutely distinguish one from the 

 other. Anxbody can tell a cow from a cabbage but nobody 

 feels very confident that he can always distinguish between 

 the animal and the plant when both are formed of a single 

 cell. Even the text-books are not always clear in such 

 matters and both zoology and botany have often claimed 

 the same organism for their own. The difficulty of exactlv 

 defining- a plant is complicated by the behavior of the fungi 

 and other parasitic plants which, in their methods of 

 assimilation, at least, are more like animals than plants. 



In one of our scientific journals, botanists have recently 

 been amusing themselves in trying to make a definition 

 that will fit all cases but without any very great success. 

 The dictionarv definitions are unsatisfactory in that they 

 all include too much or too little. The statement that a 

 plant is "an organized non-sentient being endowed with 

 vegetable as distinguished from animal life'' means nothing 

 imless one also has a definition of what "vegetable life" 

 is. Another dictionary definition says that a plant is "a 

 vegetable product nourished by gases and liquids and not 

 ingesting soHd particles of food." This is also faulty, 

 for as far as use is concerned, plants also make use of 

 solid particles, digesting them just as animals do, and later 

 oxidizing them by a process that is practically identical 

 with that of animals. 



A substitute suggested by one writer is that a plant "is 

 an organism possessing chlorophyll or descended from 

 chlorophyll possessing ancestors." Another is that a plant 

 is "a living thing which manufactures its food from the 

 raw materials of earth and air, or one whose ancestors 

 did so.'" Were it not for the fungi and other colorless 

 plants, one might at least distinguish the i>lants from the 

 animals bv the statement that "plants are living organisms 

 that unite various lifeless substances by the energy from 

 sunlight while animals incapable of doing this, secure 

 their energy by tearing down what the plants build up.'' 



Any of these definitions will answer for ordinary cases 

 and we may let the technical botanist argue about the ex- 

 ceptions, there is, however, another phase of the subject 

 which offers perhaps still greater opportunities for dis- 

 cussion. Assuming that we can always distinguish a 

 plant from other living things we are still confrontetl by 

 the problem of how much of a vegetable complex is a 

 plant The question is not so difficult in the case of 

 annual plants for one sows a seed and from it there comes 

 up a form that grows to maturity, reproduces, declines 

 to old age and finally dies. This, indeed, is a plant. W hen 

 it dies it may leave behind it a million descendants each, 

 in time, duplicating the life cycle of its parents and each 

 capable of being distinguished from its fellows. I.ut 

 what about the case when one plants the seed of the wild 

 plum or the white poplar? After a time we have not a 

 single distinct organism but a tangle of forms produced 

 from root-sprouts. Is this all one plant, or a group of 

 plants^ The banvan reverses this process and ]>roduces 

 roots from the i)ranches and gradually spreads over 

 enough territory to shelter an army. We si)eak of it as 

 a banyan tree, but it is not a tree in the sense that a pine 



tree is a tree. . 



In the strawberry, we find certain branches that are 



manifestly for the purpose of producing new plants and 

 the same is true of the "hen-and-chickens" and the straw- 

 berry geranium, which is neither a geranium -nor a straw- 

 berry. These new plants, however, are not quite in the 

 same category as those produced from seeds, for they are 

 still attached to the mother plant. The mangrove has 

 devised an improvement on this method. Its fruits do not 

 separate from the parent plant when ri])e but continue on 

 until the plantlets they contain have grown to a consider- 

 able size. Then they fall from the tree ready to start in 

 life for themselves. 



Among the lilies and "top onions'' we find bulbs and 

 bulblets that drop otT and produce new plants as distinct 

 as their parents, and we have no difiicult\- in distinguish- 

 ing between the separate individuals. Init there are other 

 lilyworts whose methods of reproduction leave us in more 

 uncertainty. The adder's-tongue or dog-tooth violet, for 

 instance, begins as a seedling and forms a bulb at the end 

 of its first year. The next year, however, this bulb may 

 send out one or more slender subterranean stems called 

 "droppers," which wander about in the earth and finally 

 produce new bv.lbs at their tips. .-Xt the end of the second 

 season the original bulb has disappeared but there are 

 several new bulbs scattered through the soil. Are these 

 separate plants, or a widely distributed single plant? 



There is a long list of plants such as irises, blood-root, 

 and Solomon's-seals whose subterranean stems branch 

 and branch again, forming a clump of considerable size. 

 How much of this clump shall we call a single plant? 

 Commonly, such forms spread out from the center in all 

 directions, forming a circle which is commonly known as 

 a "fairy ring.'' Such fairy rings were first known in the 

 fungi and named because it was supposed that the fairies 

 danced in them of moonlight nights, but now many other 

 plants are known which form similar figures. When the old 

 branches decay and disappear the branch-tips are left as 

 se]>avate individuals. Thus time alone may make several 

 ])lants out of one ! 



When man takes to multiplying plants he adds to the 

 confusion by making separate plants from pieces of an- 

 other. When he finds a form of value he may multiply 

 it excessively in this way. All the Concord grapes, for 

 instance, are but parts of one original vine. In a certain 

 sense there is only one Concord gra]>e vine in America ; 

 in another there are millions. The same is true of the 

 Xnvel orange, the Delicious apple and a host of others. 



Most puzzling of all are the lichens, which may be 

 described as the only living things in the world which 

 are entirely vegetable without being i)Iants. .Mthough 

 they have a definite shape, color, size and jjlace of growth, 

 and are comparable to plants in these respects, they are in 

 reality plant partnerships in which an alga and a lichen 

 are combined. l-"or a long time they were regarded as 

 true plants and clai-sed accordingly, but now they have 

 no standing as .separate species. Whether ihcy should 

 be classed as fungi or alg?e does not concern us at jircsent; 

 the interest in them lies in the complications they intro- 

 duce into the definition of what a plant really is. 



All nature is but art, unknown In ibee ; 



.Ml chance, direction, which thou canst not see; 



.Ml discord, harmony, not understood: 



.\11 ])artial evil, universal good: 



And spite of pride, in erring reason's spite, 



One truth is clear, whatever is, is right.— Po/r. 



