876 



HORTICULTURE 



December 30, 191S. 



The PixETUM. At one time or an- 

 other every conifer which had any 

 chance of surviving has been tried in 

 the Arnold Arboretum, and some use- 

 ful information on the value of the 

 different exotic and American species, 

 with the exception of the new intro- 

 ductions from China, as ornamental 

 trees in this climate has been obtained 

 from the Arboretum experiments. Con- 

 sidering how generally unfavorable 

 the New England climate is for trees 

 of this class, the large number that 

 succeed here is surprising, although it 

 must be remembered that in this cli- 

 mate many conifers, especially Spruces 

 and Firs, are often at their best when 

 not more than forty or fifty years old 

 and that as they grow older they grad- 

 uallv fail and lose their value as or- 

 namental trees. This is true of the 

 so-called Colorado Blue Spruce (Picea 

 pvnfjens), which is still one of the 

 most nopular conifers in the northern 

 United States, where it is propagated 

 and planted in immense numbers, in 

 spite of the tact that it early loses its, 

 value as an ornamental tree. The Blue 

 Spruce is very hardy, is easily raised 

 and grows rapidly; young plants are 

 of good shape and dense habit with 

 their lower branches resting on the 

 ground. There are two forms, one 

 with dull green ancl the other with 

 blue leaves, and the latter especially 

 appeals to persons who are fond of 

 unusual looking and sensational plants. 

 For the niirseryman the Blue Spruce 

 has everything to recommend it, easy 

 germination of the seed, quick growth 

 and unusual beauty in the young 

 plants, and therefore a certainty of a 

 quick sale. For the planter looking 

 for something more important than a 

 plant for a city garden or a small su- 

 burban yard this tree has proved a 

 failure. It is not surprising, for Pirci 

 pungens growing in small groves near 

 streams in the valleys of the Rocky 

 Mountains of Colorado, lonj before it 

 attains its full size is a thin, scrawny, 

 miserable looking tree with a few short 

 branches only near the top of the stem. 

 This tree was discovered in 1862; seed 

 was planted the following year in the 

 Harvard Botanic Garden, and one of 

 the plants raised at that time is still 

 alive in the Arboretum on the southern 

 slope of Bussey Hill where it is kept 

 as a warning for planters who are de- 

 ceived by the beauty of young plants 

 of the Blue Spruce. 



PiCE.v Engei.majinh. This tree as it 

 grows nearly up to the timber line of 

 the central Rocky Mountains, where it 

 once formed great forests, is one of 

 the handsomest of the Spruces with its 

 narrow spire-like crown, soft gray- 

 green foliage and tall trunk covered 

 with bright red scaly bark. It was 

 also discovered in 1862 and what are 

 probably the largest specimens in culti- 

 vation are in the Arboretum Pinetum. 

 Until two or three years ago these 

 were narrow, perfect pyramids with 

 the lower branches resting on the 

 ground; then the lower branches be- 



gan to die gradually without apparent 

 cause. This has continued, and the 

 stems of some of the trees are now 

 bare of branches for six or eight feet 

 from tlie ground, and their beauty as 

 specimen trees is ruined. 



Picea canadensis. This, the White 

 Spruce of British North America, is 

 a very hardy, fast-growing tree here, 

 and is one of the handsomest of the 

 Spruces which can be grown in this 

 region; but the climate of eastern 

 Massachusetts is evidently too warm 

 for it and after it is thirty or forty 

 years old it becomes thin and un- 

 sightly. 



Picea rudra. This is the Appalach- 

 ian timber Spruce and retains here 

 its beauty longer than the White 

 Spruce, for it is a native of Massachu- 

 setts and ranges southward along the 

 mountains to the high Carolina peaks. 

 It is a handsome tree with dark green 

 leaves, but it probably grows more 

 slowly than any other large coniferous 

 tree, and it is not easy to establish. 

 For these reasons it will probably 

 never be a favorite tree with nursery- 

 men. 



Picea omorika and P. orientaus. 

 These are handsome and hardy trees, 

 the former a native of the Balkan 

 peninsula, and the latter of the Cau- 

 casus. No weakness has yet been 

 found here in these trees except that 

 they too often lose their leaders from 

 the attacks of the borer which so often 

 destroys the leaders of the White Pine. 



Picea Glehmi. What the future 

 may have in store for this tree here, 

 which is a native of northern Japan 

 and Saghalien, no one can predict as 

 it has been in cultivation in the Ar- 

 boretum for only twenty-two years. 

 The trees now grow rapidly, are per- 

 fectly hardy and show no signs of 

 failure of any sort. The best speci- 

 mens here are now about eighteen feet 

 high. 



Pkea .lEZOE.Nsi.'i. This is the most 

 widely distributed of the species of 

 eastern Asia; ranging as it does from 

 the Amoor region to Manchuria, Korea, 

 and to northern and central Japan. 

 This is the only Spruce in all that re- 

 gion with flat leaves like those of P. 

 omorika and P. sitchensis of our north- 

 west coast. It has been sometimes 

 called Picea ajatiensis. P. viicrosperma 

 and P. hondoenMs. In Great Britain, 

 where it is usually incorrectly called 

 Picea Alcockiana, it grows remarkably 

 well and has been recommended as a 

 timber tree for forest planting. In a 

 collection of exotic trees made in 1870 

 by Dr. George R. Hall in Warren, 

 Rhode Island, there is a specimen of 

 this tree from sixty to seventy feet 

 high with a trunk forty-six and a half 

 inches in diameter and branches 

 spreading on the ground. In this Ar- 

 boretum and in the Hunnewell Pine- 

 tum at Wellesley this tree has grown 

 badly, losing many of its branches and 

 soon becoming unsightly. 



PicEA nicoLOR. This is one of the 

 rarest of the Japanese conifers, and 



as it grows in the Hunnewell Pinetum 

 it is now the handsomest of all the 

 Spruce trees which can be grown in 

 this climate. Mr. Hunnewell's trees 

 are now about forty feet high with the 

 lower branches resting on the ground 

 and covering a space from thirty-five 

 to forty feet across and with perfectly 

 straight stems. This beautiful tree is 

 probably better known by its incorrect 

 name of Picea Alcockiana. It is one of 

 the rarest of the Japanese conifers in 

 cultivation and it is to be regretted 

 there are no good specimens now in 

 this Arboretum. 



Picea Ames. This unfortunately is 

 the correct name for the so-called 

 Norway Spruce of Europe which has 

 generally been known as Picea excelsa. 

 Fifty or sixty years ago this tree was 

 very generally planted in southern 

 New England where it has not proved 

 a success as an ornamental tree as it 

 begins to fail at the top when about 

 thirty years old and then soon be- 

 comes ragged and unsightly. In some 

 parts of Virginia and in the Middle 

 States this is a better tree than it is 

 in Massachusetts. In the National 

 Cemetery at Gettysburg in Pennsyl- 

 vania there are magnificent specimens 

 of the Norway Spruce in as perfect 

 health and beauty as can be found any- 

 where. 



Firs. The number of Fir trees that 

 can be successfully grown in this cli- 

 mate for many years is not large. One 

 of the handsomest here is the White 

 Fir of western North America, Abies 

 concolor. There are fine specimens of 

 this beautiful tree in the Arboretum 

 raised here from seed planted in 1874 

 and now about sixty feet high, with 

 the lower branches resting on the 

 ground, and solid masses of gray-green 

 foliage. As handsome and as promis- 

 ing in this climate is the Japanese 

 Ahies homolepis, or, as it has been 

 more often called, Ahies brachyphylla. 

 This is a large tree on the mountains 

 of central Japan with dark green 

 leaves silvery white on the lower sur- 

 face and violet-purple cones. It has 

 proved perfectly hardy in this climate. 

 The largest specimen in the Hunne- 

 well Pinetum is now fifty-five feet high 

 with branches sweeping the ground. 

 The Arboretum trees are smaller but 

 already produce their handsome 

 cones. A variety of this tree. fvar. 

 umhellata) with green cones and rather 

 lighter-colored leaves is established 

 in the Arboretum where it has grown 

 raijidly, the largest specimen raised 

 from seeds planted in 1891 being 

 thirty-five feet high. Abies cilicica from 

 Asia Minor and A. cephalonica from 

 southeastern Europe are hardy trees 

 in the Arboretum and now promise to 

 grow here to a large size. Abies 

 Veitchii from Japan is still a hand- 

 some tree in the Arboretum but it is 

 doubtful if it carries its beauty to old 

 age. ,1. amabilis and A. grandis from 

 northeastern North America are hand- 

 some young trees here, and A. nobilis 

 from the same region just keeps alive 

 here as a nearly prostrate shrul>, al- 

 though in Methuen. in the extreme 

 northern part of this state, there are 

 handsome and healthy specimens of 

 this Fir nearly thirty feet high. 



PiNE.s. Among exotic Pines the 

 three Japanese species, Pi7in^ parvi- 

 flora. P. Thunbergii and P. densiflora, 



{ContiilUfd /rom page 83S) 



