Manual of Rootstocks

Ottawa 3ADwarf M9 class rootstock

Used for: Apple
Developed by: Agriculture and Agri-Food, Canada
Country of origin: Canada
Parentage: Ottawa 3

Ottawa 3A as compared to ‘O.3’; shows increased precocity, higher cumulative yield efficiency, and wider branch angles.

Ottawa 3A rootstock characteristics

  • Species compatibilityApple
  • Vigour % of standard30% - 40%
  • Rootstock size classDwarf
  • PrecocityPrecocious
  • Support requiredPermanent support
  • Cold-hardinessCold-hardy
  • Cold hardiness (USDA)Zone 4 (-34C)
  • Country of originCanada
  • Period of origin1950 - 1999
  • Virus toleranceVery susceptible
  • Woolly aphidVery susceptible
  • Fire blightVery susceptible
  • Powdery mildewSome susceptibility
  • Burr knotsNone
  • Collar rotSome resistance
  • Crown GallSome susceptibility
  • Crown rotSome resistance
  • Replant complexSome tolerance
  • Root suckersSome

Find our more about this rootstock in the 'Manual of Worldwide Temperate Zone Fruit and Nut Tree Rootstocks'.

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