28 TIMBER EOT CAUSED BY LENZITES SEPIAEIA. 



FLOATING OF TIMBER. 



The immersion of timber in water has long been hekl to increase 

 its diirabiht}^ (Dudley, 1887; P^ernow, 1890). Such tmiber seasons 

 c[iuckly after being removed from the water (Von Schrenk and Hill, 

 1903). It appears that the immersion of timber for several weeks or 

 months will decrease the decay caused by Lenzites sepiaria, although 

 no experiments have been made to determine this point. 



TREATMENT WITH CHEMICALS. 



The treatment of timber Vitli solutions of chemicals which have a 

 deleterious action on the wood-rotting fungi is by far the most effi- 

 cient method of preventing decay. There is absolutely no question 

 as to the efficiency of this method, as numerous tests show. The 

 fofiowing publications of this department may be cited in this con- 

 nection: Crawford, 1907a, 1907b; Nelson, 1907; Von Schrenk, 1902, 

 1904; Sherfesee, 1908a, 1908b; Smith, 1908; Weiss, 1907, 1908. 

 Since this fungus will not grow in alkaline media, it is probable that 

 those solutions which are alkaline will prove most efficient, other 

 conditions being alike. 



Besides the general experiments of the many who have treated 

 wood with various chemicals, there is an extensive test which has 

 given very definite results as regards Lenzites sepiaria and the decay 

 caused. by it. In 1902 (Von Schrenk, 1904) a piece of track was laid 

 with' experimental ties, both treated and untreated, in eastern Texas. 

 The following coniferous timbers were used: Tamarack (Larix 

 laricina) and hemlock (Tsuga canadensis) from Wisconsin; longleaf 

 (Pinus paUstris), loblofiy (P. taeda), and shortleaf (P. ecUnata) pine 

 from Texas. Eighteen months after the ties were placed in the track 

 the writer assisted in the examination of them. The results are noted 

 herein only for the coniferous species of wood and in connection with 

 Lenzites sepiaria. 



The untreated hemlock ties were seriously rotted, 90 out of 101 

 having sporophores of Lenzites sepiaria and of Pohjstictus veriscolor 

 Fr. The former was present on most of tlie hendock ties which bore 

 fruiting bodies. The untreated shortleaf pine had 31 out of 100 

 which showed Lenzites sepiaria. The untreated longleaf pine had 68 

 out of 93 afiected, some being badly rotted. The untreated loblolly 

 had 57 out of 100 bearing fruiting bo(fies of this fungus. Of the 

 untreated tamarack 37 out of 49 bore sporopliores of L.enzites sepiaria. 

 Of the methods of treatment tested the Wefihouse, zinc chlorid, and 

 Afiardyce j)rocesses gave satisfactory protection. The Barschall 

 process did not give good results; treatment with spirittine gave fair 

 results, and so far as Lenzites sepiaria is concerned, was satisfactory; 



214 



