Of Woods. 477 



the contiguous arable land ( 544 ). The beech excels all other 

 trees for producing great quantities of mast, which is an ar- 

 ticle much relished by hogs and deer, and yields much oil, 

 fit for various important purposes ( 54S ). 



The trees allowed to stand to become timber, in the mixed 

 woods at Holkham, are oak, ash, elm, beech, sycamore, 

 lime, sweet chestnut, locust acacia, evergreen oak, and 

 Scotch and silver firs. The underwood is chiefly oak, elm, 

 sweet chestnut, and hasel. 



In several districts of England and Scotland, there are 

 extensive tracts of natural birch. They have a beautiful 

 effect upon the scenery, and form a comfortable screen to 

 increase the warmth in such situations ; but the value of the 

 timber is much inferior to that of oak, and the bark, though 

 used for tanning leather, is much less powerful than oak 

 bark( 546 ). The mode of extracting tar from the birch, 

 particularly from its bark, which is found of such impor- 

 tance in Germany and Russia, has not yet been introduced 

 into this country. 



The rules for the profitable management of woods in ge- 

 neral, are neither numerous, nor difficult to execute. The 

 proprietor should fix on those sorts of trees, the most likely 

 to be in demand ; he should have them examined at stated 

 periods, that he may know what trees are increasing in value, 

 what stationary, and what decreasing; he should select such 

 young trees as are best adapted to keep up a regular suc- 

 cession, so as to produce the greatest quantity of timber, on 

 any given quantity of land, consistently with the growth, 

 and comparative value of the underwood ; he should cut 

 down such as are likely to obstruct the growth of the trees 

 intended to be preserved ; and he should accurately ascer- 

 tain, what period of their growth is the best suited for the 

 markets to which they are to be sent, and the purposes of 

 the consumer ( 547 ). By attention to these simple rules, pro- 

 perty in wood may be rendered much more valuable than 

 otherwise it would be. 



3. Groves. 



If profit is alone to be considered, trees, of every'species, 

 ought to be cut down, when the annual increase in Value of 

 the tree, by its growth, is less than the annual interest of the 

 money for which it would sell ( 548 ) ; and the annual value of 

 the land on which it grows ( 549 ). But such is the inadequate 

 price of large, and even middle sized timber, that it is still too 



