stances? Or will some of those chestnuts that still survive be found to 
possess inherent resistance to the blight? ; act 
These questions have been asked time after time, and a few indi- 
viduals have not yet given up hope for the discovery of blight-resistant 
American chestnut trees. 
The U. S. Forest Service has received many reports about the exist- 
ence of large and old American chestnut trees during the past decade. 
Of special interest are those reported from the Middle Atlantic States, 
the area in which the blight has been killing chestnut trees for 50 years. 
The Forest Service would like to know if these old trees are blight- 
resistant—or if their survival has been due only to chance escape. 
Because the reported trees are so widely scattered, it has been neces- 
sary to enlist the cooperation of numerous individuals. The owners of 
chestnut trees have collected herbarium specimens for authentic identi- 
fication and upon request have forwarded scionwood to be tested for 
possible genetical resistance to the blight. By making grafts of such 
material onto Asiatic chestnut rootstock, a rapid test for disease resist- 
ance can be obtained. Such tests are more significant when the grafted 
trees are exposed to natural infection of the blight in a number of 
scattered localities. 
Since the spring of 1954, the U. S. Forest Service at its Laurel Re- 
search Center has carried on an intensive testing program in coopera- 
tion with the owners of surviving large old trees. ‘The tests have been 
limited to trees having a trunk diameter greater than 8 inches at 414 
feet from the ground. 
Though the Forest Service occasionally receives scions from unusual- 
ly large old trees located outside the botanical range of our native 
chestnut, for the most part the only trees tested are those from areas 
where the blight has destroyed our chestnut forests. 
Owners send in 15 to 20 scions from the current year’s growth, taken 
from the ends of sun-exposed branches in mid-February. They label the 
material as to ownership, tree location and size, and condition of 
health. The bundle of scions, wrapped in moist newspaper with an 
outer waterproof covering, is then mailed to the U. S. Forest Service 
Research Center at Laurel, Maryland. 
Cooperators were found who would accept a limited amount of 
scionwood each spring—in early March—for grafting onto Asiatic 
chestnut rootstock. About 50 people—in federal, state, and private 
employment—expressed an interest in doing this work and they now 
receive propagating material from the trees under test. 
Ten scions representing 10 accessions are sent to each cooperator. 
They report their results in August. Even though many of the cooper- 
ators had no previous experience in grafting, their work is the basis for 
success of the program. The cooperators were given a free hand to use 
whatever grafting technique and rootstock they chose—except Ameri- 
can chestnut rootstock, since it has been found to be too susceptible 
to blight. 
Since the spring of 1954, a total of 146 American chestnut (accessions) 
trees have been included in screening tests, and a total of 4,950 scions 
have been distributed to field cooperators (table 1). Each year new 
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