ines through inbreeding. Finally, it may be possible to make
valuable individuals available to the forest owners for field planting
if they can be propagated vegetatively in large enough numbers at low
cost.

Compared to propagation by grafting, the rooting of cuttings is both
simpler and cheaper, if it can be done. Chestnut cuttings are,
unfortunately, very difficult to root. In the past six years numerous
experiments have been conducted in order to find a way to root the
various chestnut species. We have tried to root dormant, as well as
greenwood, cuttings, the conventional twig cuttings as well as leaf-bud
cuttings; numerous hormone treatments using several different hormones
in solution and as powders, over a wide range of concentrations, have
been tried; a special chamber in which an automatic atomizer nozzle
sprays the cuttings intermittently has been used. Results have always
been poor. Dormant cuttings have broken dormancy, sent out new leaves,
formed an abundance of callus on the basal end, but failed to develop
any roots, and finally after several months have died. Greenwood
cuttings also have failed to develop roots in almost all cases. The best
results have been obtained with leaf-bud cuttings. In some cases 10 to
20 per cent have rooted; here, however, the difficulty has been the
failure of the bud to break dormancy and start growth, and all the
rooted cuttings have eventually died.

The rooting by airlayering has been tried in a few cases. Airlayering is
the rooting of twigs while they are still attached to the tree. Some
distance from the terminal end of the twig an oblique cut is made, or
the bark is removed around the twig for about 3/4". The cut or ringed
area is treated with a hormone powder, wrapped in sphagnum moss and
covered with a wrapping of polyethelene. Attempts to root twigs on older
trees by this method have so far failed. Recently successful rooting of
twigs on young seedlings by airlayering has been reported from Spain,
and from France comes the report that stooling of young seedlings is
highly successful. In the stooling method the young plants are cut off a
short distance above the ground level. As new shoots grow out, their
basal ends are gradually covered with soil until a 5-6" mound has been
formed. Left in this manner they may develop their own root system and
can eventually be detached from the mother root. That the rooting of
young seedling material should be possible, while that