Just Say No to Ornamental Pear Trees!
Ornamental pear trees, or Callery pear, at first glance, are a very desirable and attractive tree for the home landscape. They are one of the first trees to bloom in the spring producing a dense canopy of white flowers. Cultivated varieties are bred to not produce fruit or thorns. They have a very upright growth habit, allowing them to be planted where space is limited. O-pears are very hardy and adaptable to most urban conditions. As such, Ornamental pears have been heavily marketed with these attributes.
Let’s take a closer look!
The flowers produced have a foul odor and most produce small fruit. The small fruit are eaten by birds and other animals which effectively disperse seeds everywhere they poop. This has made them very invasive, especially in woodlands and forests. The trees grow rapidly and out-compete native woodland flowers and trees for available sunlight.
O-Pear cultivars vary in their disease resistance, most seem to be susceptible to fire blight, an aggressive bacterial disease. Fire blight is very prominent in our area, is difficult to control, and can quickly disfigure and kill the tree if not controlled. Because of their upright growing branches, they are very prone to splitting during high winds and storms. The small fruit can leave a mess on sidewalks and driveways.
Bradford pear was one of the first to be introduced to the nursery industry, and as it turns out, became one of the most problematic cultivars. It was supposed to be disease resistant, thornless and fruit free, failing on all accounts.
Most cultivars were produced by grafting onto another more vigorous root stock and have become a problem. When the trees start to decline or die, they produce sucker growth that can develop into a new tree. The tree that develops from a sucker carries most of the bad traits of the root stock parent tree. Sucker trees with undesirable traits cross pollinate. Trees that develop from the fruit become wild and very invasive. Because of the loss of genetic control, the nursery industry could no longer guarantee that a cultivar was tagged properly in the nursery.
For these reasons, the planting of Callery pear trees is discouraged and was even outlawed in some states. Chanticleer o-pear is said to be somewhat resistant to fire blight and branch splitting.