EMLA Colt                                                          

Origin

EMLA Colt resulted from the hybridization of Prunus avium and P. pseudocerasus in 1958, as part of a long-term breeding program at East Malling to develop cherry rootstocks capable of reducing tree size and improving the resistance to disease of scion varieties.  Colt was first released as a virus-indexed EMLA clone in 1977.

Influence on Scion Varieties
Compared with trees on F12/1, trees on Colt give significantly larger crops of good quality fruit earlier in the life of the tree.  Trees are well-branched with wide angles; the final tree is 75-85% of those on F12/1 and 85-90% of those on Mazzard Seedling (P. avium).  Tree hardiness studies have shown Colt to be less winter hardy than originally thought.

Disease Resistance
Colt has shown resistance to bacterial canker, crown gall and cherry replant disease, all of which are characteristic of trees on P. avium rootstocks.

Nursery Habit
Colt has a good nursery habit, rooting very well in the stoolbed.  Colt is compatible with most popular sweet, sour and ornamental varieties.

Horticultural Value
In spite of strong consumer demand and good prices for cherries, in the last two decades, increases in picking and other costs associated with large trees have caused the acreage of cherries to fall everywhere.  Colt could provide the much needed stimulus for replanting.  In some areas the reduced tree size and earlier cropping makes EMLA Colt an obvious choice over seedling for new plantings.

The most favorable characteristic of Colt is cultivars that are budded or grafted on it provide orchards with uniform trees and freedom of some diseases common to cherry trees.