Bui. 606, U. S. Dept. of Agriculture. 



Plate VI. 



Penetration in Basswood— Heartwood (Tilia Americana). 



1, piece No. 39 treated 30 minutes; 2, piece No. 40 treated 60 minutes; 3, piece No. 41 treated 

 120 minutes. Note the penetration of creosote in the summerwood first, in the piece on the 

 left. Penetration took place readily in the summerwood because the wood prosenchyma is 

 easily treated in this species. 



