THE RED ROT OF CONIFERS 19 



periodically made at intervals not more than 20 years apart, should pro- 

 vide easily for the removal of all diseased trees. In the University 

 forest at Burlington, where such thinnings have been carried out, a 

 much better distribution of the trees has been effected. 



The present method employed in many forests of cutting to a diam- 

 eter limit, is inadvisable, because it leaves trees which may be dis- 

 eased, or which may spread the disease, or trees which on the whole 

 are undesirable from the point of view of reproduction or future lum- 

 ber production. Experienced markers should be employed who under- 

 stand the importance of such matters and who would be faithful in 

 attending to the general betterment of silvicultural conditions. 



Some lumbermen who have become interested in forestry have 

 thought that they could secure reproduction of spruce by leaving trees 

 diseased with red rot for seed purposes, thereby avoiding the financial 

 loss incurred by leaving sound trees. Such procedure is dangerous 

 because it tends to perpetuate the disease, not through the seed of the 

 old trees, but by the fungus upon them. 



It would be impracticable under existing American forestry con- 

 ditions to attempt such operations as making a complete survey to re- 

 move and disinfect fruiting bodies, unless it were in some valuable 

 grove where expense was not a factor. 



X. USES OF DISEASED WOOD 



During the writer's studies of the red rot situation in Vermont 

 lumber yards and mills, certain interesting points were noted as to 

 the methods employed in making use of the diseased wood, as well 

 as to the extent to which the fungus could destroy the wood without 

 totally impairing its value for manufacturing purposes. 



Red rot lumber, as is indicated in previous pages, is considered 

 worth about $10 per thousand. It is defined usually as "box-board 

 grade." Some manufacturers are able to use it in such ways that they 

 can afford to pay as much as $18 for it. Such lumber often is reserved 

 by dealers for local trade. As a rule it does not pay to ship it. 



The lumber graded as mentioned above, box-board grade, finds 

 its principal use in the manufacture of boxes of all descriptions. It is 

 not used alone but is mixed with a better grade in order to furnish 

 a marketable product. It is used also in making pails, tubs, kegs, etc. 

 Perhaps this is a more effective method of making use of this wood than 

 that just cited, since much poorer lumber can be used by virtue of the 



