G.16 is resistant to crown rot and fireblight. According to nursery observations, it is also immune to apple scab and replant disease, but susceptible to powdery mildew and WAA. Suckers and burrknots are very rare. This rootstock is highly sensitive to common latent virus, and only virus-free scion wood can be used. Failure to observe this will result in tree death. Slightly more vigorous than M.9, it grows very strongly in the nursery and during the first couple of years in the orchard. Growth settles down with cropping, and by the fifth year trees will be slightly smaller than those on M.26. G.16 is significantly less brittle than M.9 and has much better anchorage. We have, however, seen some union breakage in young trees as they come into bearing, particularly for brittle varieties such as Gala and Honeycrisp. We strongly recommend staking these varieties. Some customer feedback has suggested that trees on G.16 may also be highly drought tolerant. Trees will be precocious and productive, with a tendency to wide crotch angles. This rootstock is especially well suited to the propagation of Mutsu ("Crispin") and other triploids.

This rootstock came from the Geneva, NY breeding program, a cross of Ottawa 3 and Malus Floribunda developed by my father, Dr. Jim Cummins. It is Dad's favorite of his "children."