he
greater vigor of the Potomac trees may account for the fact that they
produce suckers much more freely than do trees of the Reed variety. The
habit of producing abundant suckers is an advantage in propagating by
layering, but it is a disadvantage in orchard trees because the suckers
must be removed for optimum nut production. Whether the differences in
vigor and suckering habit of the two varieties shown thus far will
affect their performance as orchard trees will have to be determined by
future observations.

Flowering Response

Each year at the height of the flowering period, each tree in the
experiment was rated on the catkins it carried. So far, there has been
no effect of the differential fertilizer treatments on the production of
catkins. However, there have been very highly significant differences
between the Potomac and the Reed. In 1950, only four of the 36 Reed
trees produced catkins, whereas 32 of the 36 Potomac trees flowered, and
approximately half of them were heavily loaded. In 1951, the number of
Reed trees producing catkins was 12 of the 36, whereas 35 Potomac trees
flowered. The amount of pistillate flowering during the two years was
small on both varieties and not greatly different; this indicates that
their nut-bearing potentialities may be about the same. The amount of
pollen produced by the Reed variety has always been considered ample for
cross-pollinating the Potomac, even though the former has been a light
producer of catkins.

Records of dates of flowering of the two original trees over a 10-year
period, and of these young orchard trees over a 3-year period, show that
there is great variability in time of flowering, depending upon the
sequence of weather events each season. Fertilizer treatments have had
no measureable effect. The trees have shed pollen as early as January
and as late as April, and stigma receptivity sometimes has continued
intermittently for two months. The average period of flowering at
Beltsville is the last week of February to the first week in March. Both
varieties have flowered at the same time under all seasonal conditions
observed. This means that additional pollinators will not be necessary
when the varieties are planted together in an orchard.

Symptoms of Scorch

The visible symptoms of scorch do not begin to appear under conditions
at Beltsville until about the middle of July or later. The first symptom
is fading of the green color, especially around th