532 Fischer . — The Biology of A r miliaria mucida , Schrader . 
amply justified, and that failing drastic action some other species of timber 
tree would have to be grown in its place. 
Prevention is better than cure, and in the case of small parks and 
avenues it is worth while to protect the trees against the entry of the 
disease. From its nature it is obvious that the fungus can enter a tree only 
by means of its spores, and these must alight on a wound from which the 
bark has been completely removed, so that they can reach the mature 
wood. Therefore, all wounds that give this opportunity should be promptly 
painted over with an antiseptic ; one of the compounds of tar is most suit- 
able. Tubeuf (27) has shown that the normal formation of wound tissue is 
not a sufficient protection, hence the necessity of an antiseptic which, 
of course, will also keep the wound secure from the attacks of other timber- 
infecting fungi. 
Where the disease has established itself all diseased branches must be 
cut off and destroyed, and the exposed surfaces must be painted over as 
before. Care must be taken to cut off the limb at a point which will assure 
the removal of all trace of diseased tissue. For this purpose, where there is 
any doubt, the aid of the microscope should be called in. 
This eradication may in some cases demand the sacrifice of the whole 
tree. As an attacked tree may live for many years, owners of ornamental 
parks may not be prepared to fell. In that case the tree must be kept 
under watchful observation, and the carpophores must be destroyed as 
soon as they appear and before they can ripen and shed their spores. 
This precaution, if strictly enforced, will preclude infection from diseased 
trees within the property, but will not insure against infection from out- 
side by wind-borne spores. In any case decaying beech stumps or timber 
should on no account be left lying about, since the fungus may live 
saprophytically in the wood and develop its fruit bodies, and become 
a centre of infection. 
When one remembers that a single spore may infect a tree, and that 
according to Buller’s calculation (4) a single fruit body of Polyporus 
squamosus , 350 sq. centimetres in area, produces 11,112,500 spores, the 
importance of a careful watch for the appearance of the fruit bodies will 
be realized, if one desires to keep the trees free of the disease. 
In forests of considerable extent such measures cannot well be applied. 
Here, the manager must content himself with removing, as far as possible, 
all diseased trees and stems exhibiting wounds at the periodical fellings. 
Also, felled timber must not be left lying in the forest. But these are 
the platitudes of Forest Science, and no stress need be laid on them here. 
