ORNAMENTAL TREES. 37 



tunate selection. The collection of living plants at the 

 arboretum is already richer in species than any other Amer- 

 ican collection, and is continually being increased by a sys- 

 tem of exchanges with similar institutions in other parts of 

 the world. Here, too, experiments are made with the seeds 

 of plants taken from widely different localities, with the 

 hope, as has already been shown in the case of the Douglas 

 fir, that additions may be made to our list of hardy trees, 

 not through what is known as acclimatization, but by using 

 seeds procured from individual plants growing naturally 

 under conditions as near like those of New England as can 

 be found. INlany interesting facts have already been ob- 

 tained regarding the adaptability of plants to our climate. 



Besides the collection of living plants, there has been es- 

 tablished an herbarium, to be used as a reference collection 

 for students and others in determining the names of species, 

 or for comparison of plants from different localities. It is 

 intended that this collection shall contain abundant speci- 

 mens of every woody plant of the temperate zone, and all 

 others that may be necessary to illustrate more fully any 

 special family or group of plants. There has also been com- 

 menced a collection of tree products, which include tho 

 wood in its natural state with the bark, any interesting or 

 valuable varieties, cones, nuts, and fruit generally of the 

 trees, and any thing in the way of raw material which they 

 may produce. 



The collections of the arboretum are already assuming very 

 considerable importance ; and its museum, in connection with 

 the living plants, will offer the student of trees, whether he 

 wishes to study them in their scientific, their ornamental, or 

 their economic aspects, facilities such as this country has 

 not before offered. 



In view, at no distant day, of the scarcity of forest-trees, it 

 is well to plant for ornament those trees which, other things 

 being equal, will be of the greatest economic value. Thus 

 of the ashes, the white ash should be planted in preference 

 to the red ash or green ash ; the sugar-maple should be 

 planted in preference to the white maple, the wood of which 

 is inferior for all purposes ; of the oaks, the burr-oak and 

 white oak are either much superior to black oaks ; and the 

 red or Norway pine, previously spoken of as one of our most 



