OBSERVATIONS ON HARDINESS. 131 



States, endure our climate well. Hamamelis Yirginica, being a 

 native, is of course hardy, but the Japanese representative, H. 

 arborea, is not fitted to our conditions. In the rose farnily most 

 of the spiraeas are satisfactory, a notable exception being Spiraea 

 canescens, from the Himalayan region, which kills back badly, 

 a regrettable fact, for its graceful habit would make it a de- 

 sirable ornamental shrub. 



In the apple family, Pomaceae, there are many desirable 

 things. Nearly all the thorn apples, excepting those from the 

 extreme south, are available out of doors. In the genus Cotone- 

 aster, however, there is a wide difference in the hardiness of 

 various species. Of those from the Himalayan region there 

 have been grown here : C. Nummularia, C. bacillaris, C. micro- 

 phylla, C. buxifolia, C. rotundifolia, and C. thymifolia. The 

 first two mentioned have proved hardy, while the remainder 

 are very unstable, even when protected by straw. Perhaps the 

 explanation of this is in the fact that the two first are deciduous, 

 while the others are evergreen, thus presenting a much greater 

 transpiring surface which must act to their undoing in the 

 changeable climate of our winters. 



Coming from Schipka Pass, high up in the Balkan Moun- 

 tains, Primus Laurocerasus Schipkaensis is tolerable of this cli- 

 mate, but I fear the alternations of freezing and thawing would 

 be its undoing in exposed situations. Of the three species of 

 Cercis grown, the only one which is not satisfactory is the 

 European species, C. Siliquastrum, the other two, C. chinensis 

 and C. canadensis being entirely hardy. 



There are so many delightful things in the Papilionaceae, or 

 pea family, that it is regrettable so few of them are satisfactory 

 in our climate. Caragana Chamlagu, from northern China, and 

 C. arborescens, from Siberia and Manchuria, are desirable sorts. 

 Colutea arborescens, from southern Europe, is also hardy. The 

 European Cytisus capitatus can also be relied upon. Lespedeza 

 bicolor, from Japan, although a showy and desirable shrub, is 

 not quite satisfactory, often killing back badly. While the furze, 

 Ulex europaeus, and the broom, Cytisus scoparius, are not at all 

 desirable from the standpoint of hardiness, both killing back 

 badly, even in mild winters. 



