582 BULLETIN 347 
year. In Table 6 are shown the results of the last set of isolations, at 
the end of one year; the table shows how well the fungus may maintain 
itself as a saprophyte. Pycnidia were formed in countless numbers on 
the peeled logs and on the cut ends of the stumps and the logs. Stromata 
and perithecia developed on some of the unpeeled logs, but none developed 
on the peeled logs. The writers have on several occasions isolated the 
fungus from woodpiles, rustic woodwork, and the like, where the trees 
were said to have been cut several years previously. 
TABLE 6. ReEsvuuLts oF ISOLATIONS FROM LOGS AND Stumps ONE YEAR AFTER TREES 
WERE CUT 
Number 
containing 
live 
Trees dead when cut mycelium 
15 logs, peeled........ ee re er ee er eee ..-. II logs 
58 logs. not pecledicn sis ac avan ese ma see es oes RES Go SEN Ode She ee HSS 46 logs 
4 stumps) peeled: was 2:4 seg 2 os Keke e Yemm te R eS REY OM SSE Re eS ewe 44 4 stumps 
13 stumps, not peeled............ ERS LSA BSS ORLA ee Seas eee ha II stumps 
Trees alive when cut 
loss tpeeledl: 2.4c, 60s < esate cs eewaee Seieyste asada ane ake oaks aca 1 log 
GS TORS, MOE PEELE «5 a5: eece enci3 5 pibeun Ss actawed a ie la cc on hap beacn apd Guides) mee eg 32 logs 
T, SUUTIP, POOLED sic o2). ssicdalel oe nisi ahtis Anctuon na etomun ayastnahina eds oun Misia INQ Seek Wee a 1 stump 
OQ StuMPS, TOb/ POOLE Masai x seis dove Gravis Pieehnes Aoe png p igre ee wlan pein Sena 8 stumps 
Where the moisture conditions are favorable, the fungus is often found 
growing luxuriantly in the bottom of piles of chips where diseased trees 
have been cut. It has also been proved, by inoculation with conidia, that 
the fungus will grow and produce pycnidia even on humus such as is 
found about the base of the trees. 
Dissemination 
That this fungus spreads with astonishing rapidity is a matter of com- 
mon observation. Not only does it spread quickly from one tree to those 
standing close about it, but it is remarkable for its long jumps across 
country. It suddenly appears in a neighborhood far ahead of the main 
line of advance, without there being another diseased tree for a distance of 
many miles. Hundreds of these isolated spot infections have come to 
notice and have given rise to much speculation as to their origin. After 
the disease has once appeared in a locality it is usually a matter of only 
a few years until the neighborhood for miles around is thoroughly infested. 
What agents are responsible for carrying the causal organism from one 
tree to another, and thus causing this rapid spread? Many answers 
have been suggested, but unfortunately most of them have been mere 
conjectures not based on experimental data. 
