dvantageous. Each operation
requires only a few minutes. Last year we put in many hundreds of
inarches, altogether, which later showed nearly 100% "take".

Owners of chestnut orchards should take advantage of this method of
keeping valuable nut-bearing trees, although with cankered areas, in
healthy, vigorous condition.

We believe that, in cutting out the diseased bark, it is advisable to
cut out also a few of the outer annual rings of wood (of course
tangentially), especially if the canker is one of long-standing, since
we know that the fungus eventually penetrates the outer rings of wood.
Since that is true, the canker might enlarge later on from this same
source of infection. Further it may also be possible for spores or bits
of mycelium to be transported upward in the sap stream and cause new
infections higher up in the tree. A thorough painting of the cut
surfaces should go far toward remedying this situation.

One can usually judge the extent of damage caused by the blight by the
number and vitality of the basal shoots, a large number of basal shoots
indicating a heavy attack. However, if the roots have been severely
injured, perhaps by short-tailed mice, as sometimes happens, no basal
shoots appear, in which case the tree is doomed.

If no blight is present, but one or more basal shoots appear (sometimes
due to shrubby ancestors), it is advisable to inarch these as an
insurance against possible trouble in the future.

This inarching process has not received the attention it deserves. There
is absolutely no reason why, if this method is followed, there should be
_any_ death from blight in resistant hybrids or in Japanese or Chinese
chestnuts, barring, of course, cases where roots are attacked by mice
(or _Phytophthora_ in warmer regions). Those of our trees in Connecticut
which have been blighted have continued in health and nut-bearing ever
since we began the inarching method in 1937 (Fig. 4). If the inarches
become blighted, they can themselves be inarched, as shown.

[Illustration: Fig. 3. Veneer crown grafting on chestnut. Photo by B. W.
McFarland, Conn. Agric. Expt. Sta. May, 1952.]

Research on Blight Resistance

[Illustration: Fig. 4. Japanese-American Chestnut, 21 yrs. old, showing
inarching begun 15 yrs. ago. Original trunk, long since dead and now
rotting, shows in center. Kept alive and vigorous because valuable for
hybrid vigor and future breeding. Sleeping Giant Chestnut Plantation,
Hamden