,THE ADVANTAGES OF AN ARBORETUM. 57 



with their various modes of training, prnnins:, and culture. In connection 

 ■with the Arboretum it would be very useful to have green-houses well supplied 

 with various economic plants, — those valuable in medicine, for dyeing, those 

 used for gums, resins, ornament, or those furnishing articles of food. 



A museum of vegetable products also would tend to make the establishment 

 complete in all its departments. This they are beginning on a large scale at 

 "Washington.* The authorities estimate that there are ;:i,248 species and varie- 

 ties of trees and shrubs which will thrive in the open air in that latitifde. 



With our severe winters, where the thermometer sometimes reaches 33° 

 below zero, and often 15*^ below, I think the number of hardy trees and shrubs 

 would be reduced to 1,200 or ],500 species and varieties besides the varieties 

 of fruit trees. 



Quite a nice start can be made in such a collection by getting all the trees 

 and shrubs which can easily be picked up in any neighborhood, and by pur- 

 chase of our nurserymen. After this we shall be obliged to resort to the slower 

 process of exchanges with like collections in our own country and in foreign 

 countries. It will need constant vigilance and some money to get trees and 

 shrubs from distant countries, through missionaries, travelers, and merchants. 



We have already begun an Arboretum at the Agricultural College. We 

 have taken several small specimens of each kind we could get in the neighbor- 

 hood, and placed them temporarily in nursery rows, where some will die, some 

 may harden, some may be used in exchange ; and when we get enough together, 

 they may be set in groups where they are to be permanently located. 



Nearly all methods have been tried in the arrangement of an Arboretum, 

 each having its advantages and disadvantages. Some try to shovv^ to the intel- 

 ligent visitor the geographical distribution alone, by having a, part of the 

 garden for plants from Europe, a part from North America, while each of the 

 Other grand divisions of the globe has its corner. Others put trees together, 

 eh rubs together, and herbs together. Others attempt to arrange them solely 

 with reference to landscape effect, though in this they must fail, to a great 

 extent, because so many of their plants are new and their habits of growth are 

 not known. 



The prevailing tendency now seems to be to arrange them in groups, accord- 

 ing to the natural orders or families. This method puts all the oaks together, 

 and near them all the chestnuts, and near these the beeches and hazels, iron- 

 woods and blue beeches. These plants just mentioned constitute one of the 

 largest and most important natural families. 



In another spot may be placed all the cone-bearing plants {coniferce) includ- 

 ing our pines, cedars, spruces, larches, and cypresses. Another order includes 

 all the poplars and willows; another, birches and alders: another, hickories 

 and walnuts. 



In each of these natural orders geographical distribution can be shown to 

 some extent, — for example, by arranging the pines from North America on one 

 side of a drive or path, and those from Europe on the opposite side. Each 

 natural order should have a large label near it, containing its name, and each 

 plant should be conspicuously labeled. These natural families can be dotted 

 here and there over the lawn, and may be easily reached by paths and drives 

 running through and around them. 



The importance of such a collection must be apparent to all cultivated 

 minds. The study of trees can not be otherwise than ennobling to all who 

 behold them, whether he be artist, botanist, arboriculturist, or man of culture 



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