308 Historical and Descriptive Account 



Fahr.], is sometimes killed by the frost, and requires protection from the north 

 and east winds, 



Ptelea trifoliata grows from 15 ft. to 20 ft. high. 



Aild7itus glandulosa is generally killed by the frost when young; yet one has 

 been spared, which, in eighteen years, has attained the height of from 20 ft. to 

 30 ft., with a head 18 ft. in diameter. 



^uonyraus europae^us, quite hardy. 



/^lex Jquifolium, although it grows wild in a forest about twenty miles from 

 Berlin, yet, in the Berlin Botanic Garden, must be grown in loam, and in a 

 sheltered situation. 



Sophora ]aLp6mca, thirty years planted, is 25 ft. high, with a trunk 9 in. in di- 

 ameter. It has suffered from the frost, and has not yet flowered. 



Virgilia lutea, six years planted, is 12 ft. high : it suffers from the frost. 



Cytisus alpinus, fifteen years planted, is 18 ft. high ; it stands every degree 

 of cold. C. iaburnum, ten years planted, is 16 ft. high: diameter of the stem 

 8 in.: it is very frequently killed by the frost at 16° of Reaumur [¥' below 

 zero, Fahr.]. 



Robinifi! [P.-J.] viscosa attains a considerable height in a short time, as do 

 the other varieties. The seeds of these varieties, when sown, come up of the 

 species R. Pseud-^cacia. 



Caragdna arborescens is, here, aconsiderable shrub, which grows well in any 

 soil. 



Gleditschzo! ferox, twenty years planted, is from 25 ft. to 30 ft. high ; the di- 

 ameter of the stem 9 in.; and the circumference of the head considerable. G. 

 horrida grows as fast, but was later planted ; and the stem, consequently, is not 

 so high. G, monosperma, the same. G. triacanthos and macracantha are con- 

 siderable trees. G. inermis grows as fast as G. horrida. 



Gymnocladus canadensis is from 15 ft. to 20 ft. high, with stems from 3in. 

 to 4 in. in diameter. 



Cercis iSiliquastrum is tender, and suffers from the cold, unless protected. 

 C. canadensis has a head 20 ft. in circumference, and flowers beautifully every 

 year: it often suffers from cold. 



Jmygdalus orientalis, and also a great many more species of this genus, 

 stand the open air. A. Persica, and two varieties of communis (amara and 

 fragilis), require a sheltered situation. 



CratEB^gus. Various species attain aconsiderable height and breadth. C. coc- 

 cinea, cordata, pyrifolia, glandulosa, flava, grandiflora, punctata, nigra, mo- 

 nogyna, and many others, are quite hardy, and very ornamental. 



iifespilus and Pyrus, the same. 



S'orbiis (Pyrus) americana, twelve years planted, is 9 ft. high. 



iSorbus (Pyrus) domestica has acquired a considerable height. 



Cydonia sinensis and japonica grow well in sheltered situations, and become 

 considerable-sized shrubs. 



Halesfa diptera, tetraptera, and parviflora, in eighteen years, attain the 

 height of from 12 ft. to 15 ft. : they are hardy, flower freely, and are very or- 

 namental in clumps. 



X)iospyros does not stand the cold well. 



Praxinus. Many species, in thirty years, have become considerable trees ; as 

 F. epiptera, expansa, acuminata, ^uglandifolia, alba, &c. Only a few species, 

 as F. elliptica, Richardz, conspicua, lucida, and one or two others, are tender. 



O'rnus grows here as a shrub, and somewhat tender. 



Catdlpa dies of cold at 20° or 25° of Reaumur [from 13° to 25° below zero, 

 Fahr.] ; yet one in a sheltered situation, in thirty years, has attained the height 

 of 25 ft. 



iaurus nobiiis does not stand the open air. L. Benzoin and Sassafras 

 grow here as shrubs. 



Nyssa stands the air in a sheltered place ; but is a weak plant. 



//ippophae stands the open air. 



^laeagnus sanguinea, latifolia, argentea, angi:stifdlia, and orientalis, are toler- 

 ably hardy, and attain a considerable height. 



