Introduced in 1952 from a cross of Merton 793 x ‘Northern Spy’ by the John Innes Horticultural Institute and the East Malling Research Station in England. MM.111 EMLA is one of the more vigorous semi-dwarf rootstocks, producing a tree about 85 to 100% the size of seedling. It is resistant to wooly apple aphid and is quite tolerant to fire blight and crown and root rots. It is fairly winter hardy and produces moderate
Because many dwarfing rootstocks have less than the desired level of cold resistance and trees on all dwarfing rootstocks require support, dwarf rootstocks are sometimes used as interstems to combine the desirable characteristics of a vigorous understock and the dwarfing interstem.
Interstem trees consist of three parts:
- A vigorous rootstock (usually MM.111 or MM.106)
- A dwarfing (usually M.9 or M.27) interstem is grafted to the rootstock. The interstem is usually about 6” long, but additional dwarfing can be obtained by