682 PROTECTION AGAINST DISEASES. 



Ehine, and consequent lowering of the water-level in the 

 soil. A similar result followed drainage in Windsor Park 

 with regard to some of the elms in the Long Walk avenue, 

 and it is not uncommon with alder-woods after drainage. 

 Continual and excessive removal of litter from a forest may 

 cause stag-headedness in immature beech forest.* It has 

 been noticed in certain two-.storied coniferous forests in 

 North America after the upper stage of trees had been felled, 

 and the sun allowed to dry up the soil-covering, that the 

 lower stage, the roots of which had spread superficially in 

 the layer of dead leaves and humus, became liable to stag- 

 headedness and death. 



(e) Stag-headedness in the Scots pine may be caused, as 

 stated on p. 441, by the fungus Peridermium Pini, such trees 

 being termed "foxy" (Fig. 293). 



It is found that though, in the case of conifers, stag- 

 headedness is speedily followed by the death of the tree, and 

 beech also speedily succumbs when similarly affected, yet 

 that some other broadleaved species, and especially oak, may 

 remain stag-headed for many decades without dying, although 

 the technical value of their timber rapidly deteriorates, and 

 their trunks may become completely hollow. 



One of the worst instances of stag-headedness, on a large 

 scale, may be seen in the State forest of Compie'gne. Between 

 1775 and 1790, an area in that forest of about 6,000 acres 

 was clear-cut and planted by a contractor named Panellier 

 with pure pedunculate oaks. The soil was either very sandy, 

 or a stiffish clay, but wherever on adjacent land oak is mixed 

 with beech and hornbeam, excellent oaks are produced. In 

 the Panellier plantations, however, now 100 to 130 years old, 

 the ground is generally bare of underwood under the oaks. 

 The bark of the oak trees is yellow with lichens and they are 

 nearly all stag-headed and have ceased to grow, presenting a 

 deplorable picture. There are magnificent sessile oak trees 

 more than twice the age of the Panellier oaks on sandy hills, 

 called Les Hauts Monts, close to these pure pedunculate 

 plantations, but these sessile oaks are mixed with beech. 



* Fiiret's " Waldschutz," translated by J. Nisbet, p. 59. Edinburgh, 1893 



