184 College of Forestry 
rather than one of cure. In the control of such diseases as 
the sap-rots we have recourse only to slight modifications of 
silvicultural practice which will enable ‘such cliseased trees 
to be marked for removal when the forest is cut. There is 
one forest operation in which a timbered tract may be easily 
cleared of diseased stems at small cost. This is the repeated 
process of thinnings or of making improvement cuttings, 
during which all diseased and backward trees should be re- 
moved. In forests of high value, with high-priced timber 
located near towns or centers of industry, jae cleaning out 
is comparatively easy and the value of the products: sold 
usually suffices to pay for the improvement cutting. In 
remote forests, however, with a small working staff, deficient 
means of transportation, and little or no market for the 
thinned-out material, such methods are impracticable. 
The sap-rot caused by Polyporus pargamenus is one of the 
most important sap-rots of deciduous. trees. Suggestions 
made for its control will apply more or less to all of them. 
So long as fires are allowed to run through our woodlots and 
forests of deciduous, trees, sap-rots will continue to be 
common. The loss of good, merchantable timber in lumber- 
ing operations due to wood-destroying fungi that have fol- 
lowed forest fires is enormous. Long Pak 913) ), in a study of 
the “ Effect of Forest Fires on Siandine Hardwood Timber,” 
made in the Ozark Mountains of Arkansas cites a case where 
on one stave sale area seventy-six trees out of every 100 felled 
had butt rot and twenty-seven trees in every 100 had worm- 
holes of some kind in them. As the author states, this means 
that after going to the expense of felling 100 trees only 
twenty-four of them were perfectly sound and suitable for 
staves; not only was there a monetary loss from the cull of 
seventy-six trees, but the expense of felling unsound trees 
must be considered. For five widely separated areas in the 
eastern part of this forest Long states that an average of 
sixty-five trees in every 100 had butt rot and twenty-six had 
wormholes sufficient to cull some of the bolts. Most of this 
loss could be traced directly to the fires so common in this 
forest. ‘The area where seventy-six trees in every 100 were 
