to other insects, the two
described here are the most frequently found. Fortunately, they are
easily controlled if a watch is kept for them.

Chapter 14

WINTER PROTECTION OF GRAFTS AND SEEDLINGS

It is not enough to make a successful graft and to watch it carefully
during the growing season, picking all sprouts off the stock, spraying
it so that insects will not chew the tender leaves and bark, bracing it
against windstorms and perching birds. Each graft must also be protected
from winter injury. For many years I have studied and experimented to
find a successful way of achieving such protection. To enumerate my many
experiments, from simple to far-fetched, would be to write another book
quite as long as this one. My conclusion, now, is that there is little
one can do to assist nature in the process of acclimatizing grafted
plants and seedlings.

I have repeatedly noticed that the place where most damage is done by
the cold is at the union between stock and graft. For example, I
observed this on the European walnuts, imported from Poland, grafted to
Minnesota black walnut stocks. Although both the buds and the wood of
the top remained fresh and green, the unions suffered severe, and
sometimes total winter injury. In grafts where the latter occurred, the
dead cells soon caused the wood to ferment and sour. Occasionally, a
small group of healthy cells succeeded in re-establishing circulation
with the unharmed, grafted top and the graft, continuing its growth,
would eventually overcome the injury it had suffered. I have seen this
occur with grafts of English walnut, apricot and pecan.

A blackbird's nest in the crotch of a small tree suggested to me the
most satisfactory guard I have yet found against this greatest of
dangers to all exotic, grafted varieties of nut trees. The nest, which
enclosed over half of the graft union, was partly composed of woolen
fibers which its builder had gathered from barbed-wire fences that sheep
had brushed against. On the exposed portion of the graft union,
discoloration indicated injury and dead cells, but on that part covered
by the nest, all the cells were alive and green. I have improved on the
bird's nest by wrapping a large wad of wool loosely around each graft
union. The value of wool is that it will not collect moisture and so
start fermentation. It allows the cells to breathe, yet protects the
union from the shock of temperature extremes. Birds will inevitably
steal