peach tree borer and oak root rot. Mazzard seedlings are
less susceptible to peach tree borer, and are also less
susceptible to collar and root rot, than Prunus mahaleb
 seedlings. They are moderately resistant to oak root rot.
Mazzard seedlings are the preferred stock on less well-
drained soil and for sweet cherry varieties incompatible
with Prunus mahaleb seedlings. Both Mazzard and
mahaleb seedlings produce a very large full size tree under
New Jersey conditions.

NC-140 Cherry Rootstock Trial Results

The North Central Regional Rootstock Trial has
been testing new dwarfing cherry rootstocks since 1987 at
25 locations across the US and Canada in comparison
with our old standard rootstocks. In the East Coast NC-
140 trials the Cultivar 'Hedelfingen' is the only cultivar
being tested to date.
A dwarfing cherry rootstock/cultivar trial is underway
at the Rutgers Snyder Extension and Research Farm to
help select cherry rootstocks for New Jersey conditions.
For additional information on the new dwarfing cherry
rootstocks refer to the world web site for the NC-140
project on cherries at:
http://orchard.uvm.edu/nc140/cherryrootstock.html

The 1987 eastern cherry NC-140 rootstock

trials. These suggestions are the results of NC-140

cherry trials planted in 1987 that tried 19 stocks. Tests

were conducted in eastern cherry states: Michigan, New

York, Pennsylvania, Wisconsin; and Arkansas, Maryland,

Ohio and Kansas, as well as the province of Ontario.

These suggestions should be treated as preliminary results.

• Mahaleb rootstock is preferred for 'Montmorency' on
  good cherry soils.
• Use 'MxM 2' for tarts on poor cherry soils.
• Consider trying Gi 148 family of Gisela^®Series for
  sweet cherries:
• Gisela 5 = Gi 148-2 will grow a tree about 40-50% of
  Mazzard.
• Gisela 7 = Gi 148-8 will grow a tree about 30-50% of
  Mazzard. (Some suckers & virus are of concern)
• Gisela 11 = Gi 195-1, about 60% of Mazzard. Gisela 11
  has a spreading branch habit, rather bushy, and is less
  susceptible to crown gall than Mazzard.

INTENSIFY CULTURAL MANAGEMENT:
Irrigation, strong annual training and pruning are
ABSOLUTELY ESSENTIAL to retain fruit size with
Gisela^®Series trees. Remember that only 'Hedelfingen'
trials are mature to date, so other varieties may give you
different results.

Pollination

All recommended sweet cheery varieties, except

Stella, are self-unfruitful and need cross-pollination. Most

recommended varieties will pollinate other varieties but

Emperor Francis will not pollinate Napoleon.

Montmorency and Meteor cherries will not pollinate sweet

cherry varieties.

62

1998 New Jersey Commercial Tree Fruit Production Guide