THE ROMANCE OF THE TREES 



E. H. WILSON 



Assistant Director of the Arnold Arboretum 



Earth's Most Venerable Brotherhood, They Take Tribute From the Changing Eras of 

 Our Planet Whilst Races of Men Rise, Live Out Their Span, and Pass Into the Ages 



"And out of the ground made the Lord God 

 to grow every tree that is pleasant to 

 the sight, and good for food, the tree 

 of life also in the midst of the garden, 

 and the tree of knowledge of good and evil." 



Genesis II, V . 8 



S^HOSE who have studied the folk-lore of primitive 

 man tell us that the legend of good and evil trees is 

 5 almost universal, and that trees are ever intimately 

 connected with man's own story of his development. 

 And rightly considered they are the noblest product of the 

 Earth. Consider how they rear themselves against gravity 

 for from 50 to 100, 200 — aye to 400! — feet; how they resist 

 the storms of every season, the winter's cold, the summer's 

 heat. They are a most wonderful expression of life, adding 

 year by year to their size — often through centuries — flourish- 

 ing whilst generations of mankind come and go. 



BUILT of myriads of minute cells piled on and around 

 each other and differentiated into tissues of varying 

 thickness and forms, all is wonderfully adapted to the work 

 to be performed in the life economy of the whole organism. 

 The big roots firmly anchoring the tree to the earth give off 

 tiny rootlets that absorb water and various food salts in 

 solution, which are carried upward through special tissues 

 to the leaves. The leaves — the lungs and chemical labora- 

 tory of the tree — breathe in from the air during daylight a 

 gas deleterious to man (carbon dioxide), break this up and 

 exhale a part as pure oxygen, essential for the life of the 

 animal kingdom. The remaining carbon and oxygen they 

 combine with the water and food salts supplied by the root- 

 lets into simple forms of sugar, which are immediately avail- 

 able as food to nourish the tree's growth in all its complicated 

 parts. So much of these sugars as are not at the moment 

 wanted are converted into forms of starch and stored away 

 for the tree's future needs. No chemical laboratory in the 

 world built by man, and fitted with all the wonderful appli- 

 ances of modern science, is half so marvellous as the leaf of 

 any one kind of tree. No system of collection and trans- 

 portation devised by human ingenuity and skill is so perfect 

 as that which serves each and every tree. 



All who keep gold-fish in a bowl or in an aquarium know 

 that green weeds of some sort must be kept in the water or 

 the fish will die. Why? Because the fish inhale all the free 

 oxygen in the water and poison themselves with carbon 

 dioxide which they exhale, unless plants are present to take 

 up this gas and in exchange give back free oxygen, thus main- 

 taining the balance in nature. So on the grander scale. 

 But for the presence of vegetation the Earth would be unin- 

 habitable for the animal kingdom in all its forms. The two 

 kingdoms — vegetable and animal — are interdependent; but 

 the vegetable kingdom is the more ancient of the two. 



THE fossil remains of plants and animals imbedded in 

 the rocks of the different geological epochs of the world's 

 life tell the story of the progressive changes that have 

 taken place during the Earth's history, from its youth and 

 adolescence to its present age. But trees by no means rep- 

 resent the oldest type of life forms in the development of the 

 vegetable kingdom; on the contrary they are fairly modern. 

 Geologists tell us that in the earliest phases of the world's 

 history of which organic remains exist, the vegetable kingdom 

 was represented by simple aquatic or semi-aquatic plants, 

 and the animal kingdom by sponges, worms, centipedes and 

 spiders. In succeeding ages land plants were developed. 

 During the period represented by our coal measures (the 

 Carboniferous period) and the lengthy epoch preceding it 

 the whole Earth became more or less forest clad with a low 

 type of vegetation mostly allied to our Ferns, Horsetails, 

 Lycopods, and ancestral forms of the Cycad and Ginkgo 

 families. 



This earliest luxuriant land vegetation — that which went 

 to form the great coal fields of the Earth — was probably 

 adapted to physical environment alone, uninfluenced by the 

 scanty animal life of the period. Reptiles and mammals 

 were then differentiated, but the former, being better 

 fitted to live upon the earthy vegetation and to survive 

 in the heavily carbonated atmosphere, increased more 

 rapidly. This increase continued through the next two 

 geological epochs and culminated in the next, the Jurassic 

 period, which is fitly termed the "Age of Reptiles." Rocks 

 of this age are prevalent in the states of Wyoming, the 

 Dakotas, Kansas and Texas ; and from these rocks there have 

 been excavated and sent to museums for preservation within 

 recent years remains more or less complete of the largest, 

 the ugliest and the most extraordinary forms of animal life 

 the world has known. 



THE development of vegetation reacted on the climate 

 and on the animal kingdom and each induced constant 

 change in the other. In due course reptiles gave place to 

 mammals, birds were differentiated, and likewise insects in 

 variety; Cycads, Araucarias, Ginkgos, Yews, Cedars, and 

 other conifers came into being; and later, broad-leaf and coni- 

 ferous trees similar to those of to-day. 



It is not my purpose to trace this progressive change in 

 further detail, but the fact I do wish to emphasize is that 

 certain isolated types of the archaic forms of trees have per- 

 sisted down through remote ages to the present day. Of 



