2 BULLETIN" 89, TJ. S. DEPARTMENT OP AGRICULTURE. 



of living trees. A record was kept of each felled and each dead tree. 

 The data taken included the diameter of stump, the average height of 

 stump (which was usually about 1 foot), the diameter of the rot in the 

 stump, the height to which the rot ascended in the butt of each tree, 

 the cause of each kind of rot found, the root-rots present, the number 

 of dead trees, the cause of death, the number of dead trees blown 

 down, and any other facts bearing on the health of the trees. Data 

 on 902 felled trees were obtained. Of this number, 477 were white 

 oaks, 302 chestnuts, 61 red oaks, 45 poplars, and the remainder 

 maples, service berries, and pines. 



GENERAL CONDITION OF THE CHESTNUT. 



HEALTH OF THE TREES. 



All of the chestnut trees over 18 inches in diameter were found to 

 have diseased tops; that is, some were " stag headed, " while all had 

 one or more large dead branches on them. Many of the larger 

 chestnut trees, especially those somewhat isolated on the edges of 

 the ridges, had been struck by lightning. These trees were not 

 killed outright, but in many cases tops, branches, and strips of bark 

 of varying sizes had been killed. In a few instances the bark had 

 been partially stripped from the tree, but usually the lightning left 

 little or no external evidence of immediate injury. A careful exam- 

 ination, however, showed that wide strips of bark had been killed, 

 especially near the bases of the trees, and that little or no callus had 

 formed around the wounds. In the majority of cases the wounds 

 had not healed, but were gradually increasing in size. This increase 

 was always greater at the base of the tree and could usually be traced 

 directly to the parasitic action of the fungus Armillaria mellea. The 

 typical rhizomorphs, or "shoe strings," of this fungus were present 

 at the bases of the trees and extended 5 to 20 feet upward beneath the 

 bark. 



Of the tops, 75 per cent were infected by a pocketed or piped rot 

 (PI. I, fig. 1) caused by the fungus Polyporus pilotae, which had 

 apparently entered through the old dead branches so common on 

 the upper parts of chestnut trees in this region. In addition to this 

 top-rot, 46 per cent of the felled trees were infected with butt-rot, 

 the bulk of which was also caused by Polyporus pilotae. 



RATE OF GROWTH. 



The chestnut bark disease was not found hi the region examined, 

 but the chestnut trees, and also the oaks and poplars, were undoubt- 

 edly dying here and there from other causes. The annual rings 

 in the chestnuts show that these trees had made a fairly rapid and 

 vigorous growth during the first 20 or 30 years; then came a period 

 of much slower growth, culminating in a period in which the annual 



