The pedigree is unknown and it was selected in England from a group of French genotypes known collectively as “Juane de Metz” in the late 1800s. M.9 is the most widely planted dwarf apple rootstock in the world and at least 30% of the trees in the U.S. are on M.9. M.9 EMLA is free of known viruses and is slightly more vigorous than the original M.9. Over the years European nurseries have selected clones
Apple Rootstock Info: MM.111 EMLA
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
Apple Rootstock Info: MM.106 EMLA
Selected in 1932 from a cross of M.2 x ‘Northern Spy’ by the John Innes Horticultural Institute and the East Malling Research Station in England. MM.106 EMLA is a semi-dwarf rootstock, producing a tree about 60% the size of seedling. It is quite precocious and productive and usually does not need tree support. It is resistant to wooly apple aphid, but is highly susceptible to crown and root rots, susceptible to fire blight, and
Apple Rootstock Info: M.27 EMLA
Selected in 1934 from a cross of M.13 x M.9 at East Malling Research station in Maidstone, Kent, England and was tested as Malling 3431. M.27 EMLA is a very dwarfing rootstock and is probably too dwarfing for most commercial situations except for vigorous cultivars on vigorous sites, but it might be considered for home gardens where a small tree is desirable.. Trees on M.27 EMLA are very precocious and productive and require permanent
Apple Rootstock Info: M.7 EMLA
Formerly known as EM VII. Selected in 1912 from unknown parentage at the East Malling Research station in Maidstone, Kent, England. Trees on M.7 EMLA produce a semi-dwarf tree about 60 to 70% as big as seedling. Trees are moderately precocious and may lean with some cultivars and may require trunk support. Trees tend to produce many rootsuckers. M.7 EMLA has been widely planted since the 1960s with cultivars such as ‘McIntosh’, ‘Empire’, ‘Cortland’,
Interstem Apple Trees
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
I want to espalier an apple tree along a garage wall. What rootstock should I use?
Espalier is a technique of pruning and training apples in two dimensions, usually against a flat surface such as a wall or fence. The rootstock that you choose needs to induce enough vigor in the scion cultivar so that growth occurs but does not produce a tree with too much vigor. The environment where you are located will alter this decision. The colder, northern areas of the United States — that is, USDA hardiness zones 3 and 4 (look up …