430 JRemarJcs and Observations suggested 



according to the nature of the plant. For those that spring 

 early, and are apt to be nipped by spring frosts, a north border 

 and cold soil are best to retard their time of starting till the 

 danger from frost is less; for those that suffer from want of 

 the wood being ripened sufficiently, as many American plants 

 which have a warmer sunmier in their native situation to ripen 

 the wood, as also for those that suffer by autumn frosts before 

 the wood is ripened, a south exposure and warm dry early 

 Soil are best: in dry soils there is not so much wood made, 

 which is more easily ripened ; and the more sun, the more 

 likelihood that the wood will be ripened before frost sets in. In 

 some late wet autumns, we have had some of the hardiest of our 

 trees killed : transplanted birch, after being some years trans- 

 planted ; oaks, that were apparently sound, dying down half 

 their length in the ensuing spring ; and seedling American 

 oaks dying off in the ensuing summer, after having begun to 

 grow ; thus showing that even the hardiest of our trees may 

 be affected, from not being sufficiently ripened in a cold wet 

 autumn. The presence of a stream or river is generally al- 

 lowed to increase the tendency to slight frosts in spring and 

 autumn. The surface of the water, as it condenses by cold, 

 descends to the bottom, and a warm stratum succeeds to the 

 surface ; and so far the tendency is towards heating, rather than 

 cooling the air; but the great evaporation that takes place 

 through the day, and early in the evening, robs the air of so 

 much caloric, that fields situated near shallow rivers, streams, 

 and bogSj have generally been found most liable to frost : near 

 the sea, or near great bodies of deep water, the first-mentioned 

 effect, of a succession of warmer stratums to the surface, pre- 

 vails, and we have less tendency to freezing. Watering in the 

 morning early, if the frost has not penetrated to the juices of the 

 plant, may, by washing off the cold dew, prevent the frost from 

 penetrating; and covering from the sun may save a plant par- 

 tially^ hurt from the excessive change of temperature, if a bright 

 sunny day succeed the frosty night : but no power on earth 

 can recover the plant if the juices have been expanded by 

 freezing till the vessels are burst, which may be known by the 

 change of colour in the leaves by the suffusion of the sap. If some 

 of the most tender leaves only are hurt, on the young growths, 

 the plant may survive^ if the wood is generally young and suc- 

 culent, as in seedlings, dahlias, &C.5 the whole plant generally 

 perishes, unless where there is an old ripened root or wood to 

 renew vegetation. Some plants, as beech, that throw out or 

 evolve most of their young buds in spring, are apt to perish, even 

 though some years' old, before the latent buds can spring; the 

 oak, ash, &c., that have always spare buds, are not so apt to 

 perish. As to the acclimatising of plants, I am of Mr. Beaton's 

 opinion, that we cannot alter the constitution of a species, 



