228 BRITISH FOREST TREES 



essentially in treatment from the surrounding woods, and 

 practically forming pure forests on a small scale. 



Its treatment in pure forest is as a rule rather as coppice 

 than as high timber forest, after its growth has once been 

 begun ; the original formation of crops usually takes place by 

 means of planting rather than by either natural or artificial 

 sowing. When the stools are young, and the area is not sub- 

 ject to inundation in spring, the fall takes place close to the 

 ground, but when, on the contrary, the stools are old, and the 

 soil inundated, larger stumps are left standing. The growth 

 of the stool-shoots, which are usually numerous and not 

 spreading, is very vigorous on the more favourable classes 

 of soil ; but the rate and continuance of their growth in 

 height, the total production of timber, and the repro- 

 ductive capacity of the stools, depend to a very great 

 extent on the general quality of soil. The best marshy soils 

 are those having good loamy, limy, or marshy subsoil, but 

 most extensive marshes have only a sandy, stony, or clayey 

 substratum, or consist of deposits of peat with humose sur- 

 face-soil. Stagnating, sour water, or a large percentage of 

 iron held in solution, spoils the quality of marshy soil ; 

 whilst from the low levels they sometimes occupy they 

 may at all times of the year be too wet for sylvicultural 

 operations to be properly conducted. Whilst willows and 

 aspen are the first trees with which cultural operations can be 

 begun so long as the soil is still too wet for the alder, any 

 spontaneous growth of birch, pine, and spruce, indicates that 

 the requisite quantity of soil-moisture is no longer available, 

 and that a change in the crop would seem advisable. 



On the better classes of soil suitable for the alder, such 

 as moist loamy deposits with excess of moisture throughout 

 the summer months, the growth in height and in average 

 annual increment does not culminate until the twentieth or 

 twenty-fifth year, and continues without marked decrease 



