Landscape Plants of the Upper Midwest

Korean Mountainash

{Picture of Korean Mountainash}

Plant Information

  • Plant Type: Tree: Medium
  • Scientific Name: Sorbus alnifolia Play audio of plant name
  • Family: Mountainash
  • Zone: 4
  • Plant Size: 25-35'
  • Bloom Time: Spring
  • Bloom Color: White
  • Habit: Upright: oval
  • Culture:

    Very adaptable. Like other Mountainash, planting on a hot dry site will greatly shorten itÀs useful like by predisposing it to disease and insect

  • Notes:

    A wonderful ornamental tree, certainly the finest mountainash. The white flowers appear in small clusters in May followed by a splendid display of pinkish-orange fruit in fall. The simple leaves (different from the more common mountainashs) turn a beautiful red-orange in fall. Unfortunately, it has been recorded to be susceptible to fire blight in the Midwest and for this reason should be used with caution.

  • Pruning:Pruning animation

    Structural pruning targets branch defects with the goal of producing strong-branched, long-lived trees with a low risk of storm damage.  The importance of addressing branch defects when trees are young cannot be over-emphasized. The suppression or removal of small branches is far easier and better for long-term tree health than when branches become large.  Beginning when a tree is planted, it should be evaluated each year and branches with structural defects should be suppressed, or if small, removed.  This will promote a resilient tree structure that is also more ascetically pleasing.    

    These site explain the fundamentals of structural tree pruning:

    Urban Tree Foundation – Structural Pruning

    University of Florida – Structural Pruning

    If a branch needs to be removed for clearance, is damaged, or possesses a critical defect, a 3-point cut is used (see animation). First an undercut is made to prevent bark from tearing down the trunk if it remains attached to the falling limb. The branch is then "stub cut" which removes most of the branch to facilitate a clean final cut. The final cut is made just outside the branch collar, which is the swollen area between the branch and the trunk. Cuts made here will heal most readily and prevent rot from invading the main trunk of the tree, a common occurrence when branches are cut flush with the trunk.

© 2021, All Rights Reserved.
Landscape Plants of the Upper Midwest

Bill Hoch, Associate Professor
Montana State University

Design by Big Rose Web Design