White Flowering Bradford Pears Have a Dark Side
Brian Jervis: Ask
a Master Gardener
Mar 31, 2018
Q: What are these
beautiful trees I am seeing all over town with the white blossoms? TP
A: You are probably
referring to the Bradford pear. While they are beautiful and quite popular,
they have a dark side. But first, let’s talk about what they are and how they
got here.
The Bradford Pear (Pyrus
calleryana “Bradford”) was first introduced to the United States in the early
1900s as a way to help control fire blight of the common pear. By the ’80s, it
had become the second-most popular tree in America, primarily as an ornamental
tree.
The Bradford grows
rapidly (12- to 15-foot increase in height over an 8- to 10-year period), to a
height of 30 to 50 feet tall and 20-30 feet wide with a short to moderate life
span of 15 to 25 years (less if we get an ice storm).
Most people are
attracted to the Bradford Pear for its showy white flowers that appear in
spring. The flowers are beautiful but, unfortunately, have an unpleasant
fragrance. Early spring flowering can last two weeks, but late frosts may
reduce bloom time.
Sounds like a great
tree. Well, that’s what many of us thought until we got to know its dark side.
Although the Bradford
pear was originally bred to be sterile and thornless, they easily
cross-pollinate and produce fruit. These fruits are like tiny, hard apples,
round, ½-inch in diameter, greenish-yellow flecked with whitish spots,
inedible, with 2-4 black seeds. After it freezes in the fall, the fruit softens
and becomes palatable to birds that help spread the tree.
Unfortunately, these
offspring revert back to the thorny variety of their origin. They are not
usually noticed until spring when we see them along the highways. These
descendants are also quite invasive and tend to displace native plant
communities, disrupting natural succession. All those white-blossomed trees you
are seeing outside the fence line of the highway are likely the thorny
offspring of the Bradford pear.
So, what do we do in
response to what we now know about the Bradford? In spite of the fact that
Bradford pear trees are well adapted for Oklahoma climatic conditions, just say
no. There are a variety of other trees that work well in Oklahoma without the
Bradford’s invasive side effects. They are also quite weak, making them poor
choices to deal with Oklahoma winds and ice.
If you have a Bradford
pear, you might need to consider replacing it, and if you are looking for a
spring-flowering alternative, you should consider a redbud or dogwood tree. For
more information on which types of trees do well in Tulsa, visit the Hot Topics
section of our website, tulsamastergardeners.org,
and download a copy of our info
sheet: “Trees for Tulsa.”
Garden tips
- Most bedding plants, summer-flowering bulbs, and annual
flower seeds can be planted after danger of frost. This happens around
mid-April in most of Oklahoma. Hold off mulching these crops until spring
rains subside and soil temperatures warm up. Warm-season annuals should
not be planted until soil temperatures are in the low 60s.
- Don’t plant tomato sprouts too early. The soil
temperature is key and should be above 60 degrees before planting. If the
soil is too cool, the plants will sit there and not grow. Remove the
blossoms from any tomato plant at the time of planting; it needs roots
before making tomatoes.
- You can find some wonderful tomatoes, herbs and flowers
for your garden by shopping online during our plant pre-sale. This is the
last week of the sale. Visit our website, tulsamastergardener.org, for
information.
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