PRUNING- OF PINES. 



357 



young plants are tender, and require protection in 

 winter, three or four stakes driven into the ground, 

 and rising a few inches above the top of the tree, and 

 covered with matting or spruce-fir branches, will gen- 

 erally afford sufficient shelter. Some protect the lead- 

 ing shoot by a bell-glass, or cap of felt, supported in 

 the same way. For subsequent cultivation, little more 

 is required than the clearing away of long grass and 

 weeds from the young plants, and the thinning out 

 of nurses, where that mode of protection has been 

 employed. 



Pruning of Pines. — The fir tribe, when grown in 

 close plantations, require little or no pruning. In the 

 pinetum, a moderate application of- the knife is bene- 

 ficial to many of the species. Owing to differences 

 of climate, or variation in the pressure of the atmos- 

 phere from differences of altitude, some of the sorts, 

 which are tall trees in their own countries, are apt to 

 grow bushy with us ; or, from accidental circumstances, 

 some of the higher lateral branches may show a dis- 

 position to compete with the leading shoot. In all 

 these cases, the thinning-out of the branches, especially 

 the small ones, and the foreshortening of those which 

 are acquiring an excessive or irregular luxuriance, will 

 be found useful, particularly in the (Jedrus, Picea, and 

 Abies groups. The object kept in view should be to 

 direct the flow of sap to the head and shoulders of the 

 tree ; but it ought to be regarded as a first principle, 

 that by pruning the natural form of growth is to be 

 promoted, and not constrained into any thing artificial. 

 Mr. M'Nab, of the Edinburgh Botanic Garden, who 

 has inherited and acquired much experimental knowl- 

 edge in this department of arboriculture, has found 



