February 6, 1895. 



Garden and Forest. 



53 



while examining carefully tlie Cork-trees of Cintra, which 

 usually fruit abundantly, we found very few biennial fruits, 

 and on the same branches we saw the cups of fallen acorns 

 with annual insertion. We will add that in Welwitsch's speci- 

 mens, collected at Cintra, many are found with mature annual 

 fruit, to one of which he affixed the following note : "Proba- 

 biliter nil nisi forma O. Suberis, L., squamis cupularum plus 

 minus hebetatis. Fructus pleniter maturi et alii sat juveniles, 

 nee non fructus maturescentes saepius in uno eodemque pe- 

 dunculo inveniuntur I 1 " We will add, moreover, that we 

 examined from Coimbra, whence we had numerous biennial 

 specimens, some others perfectly identical, with annual fruit, 

 and Sr. Moller, at our request, examining again (the end of Feb- 

 ruary) these trees, found very few biennial fruits, this appa- 

 rently not being a common occurrence there. 



6. ft is no wonder that in certain places of great humidity, as 

 Cmtra, Coimbra, etc., the Cork Oak has an almost continuous 

 growth and easily produces liiennial fruit. It is also in such 

 places that other species of the genus Ouercus (0. Lusitanica, 

 O. humilis, O. pedunculata) frequently make (especially the 

 first) two new growths, an indication of more continuous 

 vegetation. 



7. It is worthy of note that in various parts of the country 

 it is said that certain men experienced in rural affairs know 

 in winter whether the following year will be abundant in 

 "bastao" (the first crop of acorns) by the presence of very 

 small fruit, which, in this condition, they alone recognize. This 

 fact appears to confirm the accidental presence or absence of 

 fruit in the process of biennial maturation. 



8. From what we have said, the maturation of the Portu- 

 guese Cork-tree cannot be said to be strictly either annual or 

 fjiennial, but rather sub-continuous, hardly interrupted by the 

 cold of winter ; and for this reason it is impossible to base 

 specific distinctions on the differences of this maturation. 



In the same paper there is an interesting account of the 

 hybrid Oaks thus far detected in Portugal. Among the 

 eight indigenous species, four of these supposed hybrids 

 have been found. r r jp 



Arnold Arboretum. c.. Jl,, r (1X071. 



•Tiie White Elm in the West. 



THE Elm is one of several trees that are invariably 

 recommended for planting in the west, but for which 

 hardly any economic use is known. The timber is tough 

 and hard, and is used in making wheels and saddle-trees, 

 but its use about the farm is limited, as it is not durable 

 in contact with the soil, and it is very difficult to season. 

 Too much can hardly be said of its beauty of form, but in 

 close forest-growth this is of small importance. It is native 

 as far west as central Kansas, and a little farther in Ne- 

 braska. It endures low temperature well, and large speci- 

 mens are found along the Red River in North Dakota. 

 Although its habitat is always near streams or lakes, where 

 its roots have a constant water-supply, it makes better 

 growth in dry situations than many other species, and is 

 altogether superior for high land to Black Walnut and Cot- 

 tonwood. Thus far it has been quite free from insect pests 

 in the west, but it can hardly hope to escape the destruc- 

 tive beetle that is defoliating the Elms throughout the east. 

 In South Dakota cut-worms often cause great damage to 

 seedlings, and they even climb into two and three year old 

 trees and eat off their leaves. The larva of the emperor 

 moth also attacks the foliage. 



In rapidity of growth the Elm is one of our most satis- 

 factory hard woods. In the South Dakota Agricultural 

 College plantations, at Brookings, White Elm planted with 

 Bo.x Elder si.x years ago now equals the Bo.x Elder in 

 height, though for the first three years the latter tree grew 

 the more rapidly. In a plat of hard woods, White Birch 

 grew most rapidly, then White Elm, Black Wild Cherry and 

 Green Ash, with but little difference between the three first 

 named. At Hutchinson, Kansas, in the railroad plantation, 

 now about twenty-four years old. White Elm and Cotton- 

 wood were planted in alternate rows. The Cottonwoods 

 now stand from fifty to sixty feet high, and the Elms are 

 completely overtopped, being scarcely thirty feet high, and 

 making feeble growth. 



In another part of the plantation, where their neighbors 

 are Honey Locusts and Silver Maples, they are doing very 



much better. The Elm is a light-demanding tree, and does 

 not succeed where overtopped by other species. At Far- 

 lington, Kansas, an Elm that has evidently sprung from 

 seed in a plantation of Catalpa speciosa has outstripped 

 the Catalpa both in height and diameter. No Elms were 

 included in this plantation, and comparisons cannot be 

 given. The trees at Brookings stand in a rich loam above 

 stiff clay, and those at Hutchinson are in the sandy loam 

 of the Arkansas valley, with water within ten to twelve 

 feet of the surface — an ideal soil for the Elm. 



Several of the newer streets in Denver, Colorado, are 

 planted with White Elm, and under irrigation the trees fully 

 equal the best growth observed in the east. 

 Washington. CJiarks A. Keffer. 



Foreign Correspondence. 

 London Letter. 



Dendrobium Wattii. — This plant first flowered at Kew in 

 October, 1882, soon after it had been received from Dr. 

 Watt, the Indian botanist, who found it in Munipore. It 

 was figured and described by Sir Joseph Hooker in the 

 Botanical Magazine, t 6715, under the name of Dendrobium 

 cariniferum, var. Wattii. In 1888 Professor Reichenbach 

 elevated it to the rank of a species because of its differing 

 from D. cariniferum in having slenderer stems, narrower 

 leaves, larger flowers and a terete, not triquetrous, ovary. 

 Sir Trevor Lawrence exhibited it m flower this week, and 

 it was awarded a botanical certificate, although it merited 

 the highest award. The flowers are borne in pairs on short 

 racemes, and there are six or eight flowers on the apex of 

 each stem ; these are two inches across, pure glistening 

 white, with streaks and a blotch of deep yellow on the 

 front of the labellum. In effect the flowers are equal to 

 those of D. infundibulum (Janesianum), and nearly as fine 

 as D. formosurn, to which D. Wattii is closely allied. 



Saccolabium Mooreanum. — This is a pretty little Orchid 

 which we owe to Messrs. F. Sander & Co., who introduced 

 it from New Guinea along with Dendrobium Phaljenopsis, 

 and with whom it flowered in October, 1892. It is named 

 in compliment to Mr. F. Moore, the keeper of the Glas- 

 nevin Botanical Gardens, where there is an exceptionally 

 rich collection of Orchids. Two plants of it are now in 

 bloom at Kew — one, the type, having rose-purple flowers, 

 the other, white flowers. The plant is less than six inches 

 high, with distichous leaves, four to six iirches long by an 

 inch in width, the apex bilobed. The scape is horizontal, 

 six inches long, bearing a conical raceme, two inches long, 

 of crowded small flowers, which in the type are a pleasing 

 shade of rose-purple, the segments tipped with bright 

 green, while in the variety they are milk-white, with green 

 tips. As a garden-plant this species takes rank vi'ith such 

 Orchids as Saccolabium ampullaceum, S. Hendersonianum, 

 Phalsenopsis Parishii, Masdevallia triglochin and similar 

 diminutive, but charming as well as interesting things. 



MoRMODES RoLFEANUM is haudsome enough to be classed 

 with good garden Orchids. It was introduced four years 

 ago from Peru by Monsieur Linden, and named by him in 

 compliment to Mr. Rolfe, of Kew. There is a colored plate 

 of it in Lindenia, 1891, t. 289, and there is a plant of it in 

 flower at Kew now. It has a two-flowered scape six inches 

 long, and the flowers are as large as those of Mormodes 

 luxatum, but colored tawny yellow, shaded with green on 

 the sepals and petals, while the twisted lip is colored 

 apricot-red. All the Mormodes, with their cousins, the 

 Catasetums and Cyqiioches, are worthy of cultivation, but, 

 as a rule, they do not like to be cultivated ; at any rate, 

 they are rarely seen in good condition after they have had 

 about two years of artificial treatment. They do best when 

 grown in baskets suspended near the glass in a hot moist 

 house till they have finished their growth, when they should 

 be placed in a drier, airy house and rested thoroughly till 

 the growing season comes round again. Of course, they 

 grow in summer and rest in winter — that is, when they 

 behave properly. 



