LIABILITY TO FROSTS 37 



Spanish Chestnut, Larch (the Japanese perhaps more so 

 than the European), Douglas Fir, Cupressus macrocarpa^ and 

 Spruce (the Norway Spruce perhaps more so than the 

 Sitka) and Oak. 



Whereas, those trees which are hardiest in respect of 

 these frosts, and usually not injured thereby, are Scots Pine, 

 Corsican Pine, Austrian Pine, Birch, White Poplar, Aspen 

 Poplar, and Ctipressus sitchensis. 



But there are some trees which may be said to occupy an 

 intermediate position in this respect, and they are : 

 Sycamore, Norway Maple, Alder, Thuya gigantea, Lime, 

 Black Poplar and Black Italian Poplar, Hornbeam, Abies 

 concolor and Elm. 



With reference to this matter, the date at which tender 

 species break out into leaf is a most important point. For 

 instance, Oak (j>edunculatd) often escapes because it is late 

 in breaking into leaf, and Sessile Oak, which is more tender, 

 is usually somewhat later in breaking into leaf. And so 

 with Nordmann's Silver Fir, a very tender species, but one 

 which usually escapes because it is so very late in starting its 

 new growth. 



It will often happen that certain species of trees appear 

 frost-hardy in one instance and not in another, and in order 

 to account for these differences, it is necessary to ascribe 

 them to the individuality of the particular trees, and the pre- 

 disposition of certain seedlings to suffer, which have been 

 raised from the seed of particular trees growing in particular 

 localities ; whereas the produce of seed of the same species of 

 tree, but obtained from another locality or another climate, 

 may be perfectly hardy. 



(3) Choice of Seed. 



There can be no doubt that, generally speaking, the 

 liability to spring frosts is very greatly increased in the 

 case of seedlings of tender species, raised from seed which 

 has been grown abroad in a country where there is a very 

 short spring, and where there is a rapid transition from 

 winter to summer, and where active growth is long delayed 



