Forest Work for the Mouth. 649 



narrow trench somewhat deeper than the ordinary drain, and h^y in 

 the bottom a tliickness of several inches of broken stone. Place 

 the draining'pipe upon the bed of stones, and well puddle its 

 sides and top. The water finding its way into the stones, will 

 rise up and be carried off through the pipes without the risk of 

 the roots following it. Ordinary drains laid upon the bed of soil 

 itself would soon be filled up with roots. 



The benefits of good drainage are most observable in plantations 

 of larch and sweet chestnut, and also in a less degree in those of ash 

 and birch. Larch will grow rapidly in land moderately deep and 

 porous. Upon very stiff and wet land it does not root sufficiently 

 deep to prevent the young trees blowing up when exposed. Sweet 

 chestnut will also make rapid progress upon dry, sandy, or gravelly 

 land with moderate shelter, and it attains large dimensions on a deep 

 and dry sandy loam ; upon wet and cold-bottomed land it does not 

 mature its wood ; consequently the young shoots are very liable 

 to injury from frosts. Its rapid growth, and the durability even 

 of its sapwood in hop-poles, makes this a valuable coppice wood. 

 Use plants of chestnut which have been two years transplanted in 

 the nursery rows. When the seeds are put into the nursery cover 

 them with 3 or 3| inches of good soil. 



Observe that though ash will grow and even flourish on moderately 

 wet land, yet the toughest, and consequently the most valuable 

 • wood is grown on land not over-fertile, but light and moist. 



Plant birch on light stony or sandy land, even where the quality 

 is inferior. It flourishes over a wider range of soils than most trees. 



Eeally healthy vegetation cannot exist where water stagnates, as 

 plant food becomes too much diluted, and owing to the increased 

 evaporation the temperature of the plant is always low, so that all 

 chemical changes are retarded. Even where there is lieat as well 

 as moisture, if air cannot reach the roots, the produce is leaves 

 alone, and not fruit. Deep drainage supplies the roots with air, as 

 air always follows descending water, whereas surface evaporation 

 checks the descent of air. Where the sun's heat is exhausted in 

 evaporating water, it cannot warm the soil. 



The drainage of peaty and clay soils is especially desirable, as when 

 well filled with moisture and afterwards dried b}' the sun these soi^s 

 lose about twenty per cent, of their former bulk. By this means the 

 roots of trees embedded in them become so compressed that air is 

 entirely excluded. 



Push on the falling of all hardwoods except oak. It may 1 e 

 necessary to look over and again daub young transplants, as rabbits 

 generally pay greater attention to these tlian to the seedlings which 

 spring up in the wood. 



