14 



GARDENERS' CHRONICLE 



The Vital Relation of Trees to Human Life and Wild Life 



HON. MARTIN L. DAVEY 



YOU know, we emphasize the word "freedom'' here 

 which means that we do as we please ; "every man 

 for himself and the devil take the hindermost." 

 \\'e started out, then, to cut a pathway for civilization 

 across the land of freedom, and in doing so we have suc- 

 ceeded to a large extent in unbalancing the whole scheme 

 of Nature. The trees, as individuals and in groups, are 

 essential to all other forms of life. The bird life i.-; ab- 

 solutely indispensable for the protection of your trees, 

 and those two things together, linked up with other forms 

 of life, make the essential background for human life. 



You know the average person does not seem to realize 

 that the tree is a living thing, really alive. Oh, I suppose 

 when you remind a man of the fact that it is alive, he 

 will saj^ "Yes," but he doesn't realize that it is really a 

 living organism. It has a breathing apparatus and diges- 

 tive organs ; it has a circulation ; it has sexual processes. 



The tree breathes through its leaves, chiefly ; the under 

 side of the leaf is a mass of small openings, myriads of 

 them, into which the air penetrates and gives up its car- 

 bon dioxide to be combined with the other food elements 

 that are already in the leaf, having been brought up from 

 the roots, and the oxygen is thrown off again for the 

 benefit of man. It is true that this breathing process does 

 not follow the principle of the bellows as in the human 

 lungs, but it is just as real breathing as occurs in any 

 other form of life. 



Then the tree has a circulation, just as truly as you and 

 1 have. Away down under the ground the little roots 

 gather up mineral elements in solution; that is carried up 

 in the sapwood all the way to the leaves and there under- 

 goes the chemical change which makes it tree food. But 

 in order that you can get this as a picture, I will ask you 

 to imagine you are looking at the top of a stump, the 

 cross-section of a tree. Right in the center you see the 

 pith and around that succeeding layers of wood, each rep- 

 resenting a year's growth. Originally, each of these 

 layers in its turn was sapwood and served the purpose 

 of a sap carrier. As it fulfilled that purpose and more 

 layers were added, it became more and more dormant, so 

 that in a large tree all these cells near the center are 

 I)ractically dormant, and as you go outward toward the 

 bark you find the wood more and more active as a sap 

 carrier. The last few layers just inside the bark are the 

 most active; it is there where most of the sap goes up. 

 The sap is pumped up from down underneath the soil and 

 carried all the way up to the leaves, irrespective of the 

 height of the tree — sometimes one hundred feet, some- 

 times one hundred and fifty feet or more — there it is 

 transformed, digested. The mineral elements that were 

 taken up in solution are comljined by a wonderful process 

 with the carbon that is extracted from the air, and that is 

 all done in the leaf. 



The leaf is probably the most wonderful factory that 

 ever existed — more wonderful than any factory that man 

 creates. It is there in the leaf that all food is created, 

 food for man and food for vegetatitjn. In the leaf, under 

 the influence of sunlight, this digestive i^rocess takes ])lace 

 which creates the food that makes possible the continuity 

 of all life. 



Everything we eat, everything we wear, is manufac- 

 tured in the leaves of vegetation. It is impossil)le for 

 man U> take into his system directly any mineral elements 

 other than water and salt, and relatively small quantities 

 of those; all others must first jiass thrr)ngh the leaves of 



vegetation and be transformed into organic substances. 

 Thus we find that the leaf, speaking of vegetation gene- 

 rally, is the one and only connecting link between the 

 organic and the inorganic worlds. And the great God who 

 created the world and the life that inhabits it, made of the 

 lowly leaf the greatest and most wonderful instrumen- 

 tality of that life. 



I have told you about the tree's breathing and its cir- 

 culation. I have tried to describe, in a way, its digestive 

 process, and now I want to tell you just a little about its 

 sexual processes. In all life there are two fundamental 

 principles ; one is self-preservation and the other is repro- 

 duction. All living things must follow both of these prin- 

 ciples and be governed by them. This is true of the tree 

 as it is of other forms of life. The tree has its sexual 

 organs in the flowers just as real and just as beautiful 

 as in other living things. The male and the female exist 

 as positive factors, sometimes in the same flower, some- 

 times in different flowers on the same tree. Sometimes 

 you find the flowers of one tree all male or all female. 

 The pollen is created in the male parts, is carried largely 

 by the winds to the female organs, and there the wonder- 

 ful relation takes place which carries the life on from one 

 generation to another — a wonderful and a beautiful pro- 

 cess. And thus we see that although the tree lacks the 

 power of locomotion, though it has no intelligence and 

 no nervous system, in all the other chemical princijiles 

 it is just as truly alive as man himself. 



Another very important phase of the tree question is 

 reforestation. It is an aspect of the matter that comes, 

 I know, very close to your hearts, as- it does to my own, 

 because it is bound up closely with your particular prob- 

 lems. I must say that anyone who is solid on the idea 

 of reforestation is bound to be solid on the idea of pro- 

 tecting wild life ; and having given some study to the 

 subject I must confess that I am solid on the desirability 

 of the passing of the Public Shooting Ground — Game 

 Refuge Bill. I wish that I were now in Congress so that 

 I might help along this worthy project. 



In order to make you understand that these statements 

 are not the result of my imagination and that they do not 

 follow the princi})le that "the wish is father to the 

 thought," I am going to read to you just briefly from the 

 report of the United States Forest Service to the Senate, 

 published about the first of June, 1920. This was in re- 

 sponse to a Senate resolution : 



"The outstanding facts reported by the Forest Service 

 arc : 



"1. That IJn-ee-fifths of the original timbi-r of the 

 United States is gone and that we are using timber fcnu- 

 times as fast as we are growing it. The forests remain- 

 ing are so localized as greatly to reduce their national 

 utility. The bulk of the population and manufacturing 

 industries of the United States are dependent upon dis- 

 tant supplies of timber as the result of the depletion of 

 the jirincipal forest areas cast of the great jilains. 



"2. That the depletion of timber is not the sole cause 

 of the recent high ])rices of forest jiroducts. but is an im- 

 portant contributing cause whose ellecls will increase 

 steadily as depletion continues. 



"3. Tliat tile fundamental problem i- lu increase tlie 

 production of timber by stoi>ping lorest devastation, 

 i'lie virgin ior^.-i^ of the Unite;l States covered 822.000,- 

 000 acres: that are now shiinik lo one-sixth of that area. 

 .\li classes of forest land, including culled, burned, and 



