September Color Appears at the Washington Park Arboretum

September 16th, 2012 by Pat Chinn-Sloan

“Ornamental Late Summer Fruits”

Selected cuttings from the Washington Park Arboretum (September 10-14, 2012)

1)  Betula lenta  (Sweet Birch)

  • The fruit, maturing in fall, is composed of numerous tiny winged seeds packed between the catkin bracts.
  • Twigs, when scraped, have a strong scent of oil of wintergreen.
  • Several specimens are located east of Azalea Way bordering the wetland bog.

2)  Liriodendron tulipifera  (Tulip Tree)

  • The fruit is a cone, two to three inches long, made of a great number of thin narrow scales attached to a common axis. These scales are each a carpel surrounded by a thin membranous ring.
  • Another eastern North American tree which is also considered the tallest deciduous angiosperm in the world.
  • A mature grove is located in our Magnolia Collection.

3)  Magnolia sieboldii  (Oyama Magnolia)

  • The ornamental three-inch-long carmine fruit dangles off the tree, and eventually busts open to reveal orange “alien” seeds from “outer space”.  The fruit are oval in shape and have little spine-like points that create an interesting texture.
  • Shrub native to eastern Asia in China, Japan, and Korea.
  • Located just outside the west entrance to the Graham Visitor Center.

4)  Ostrya carpinifolia  (Hop Hornbeam)

  • The fruit form in pendulous clusters, 3-8 cm. long with 6–20 seeds; each seed is a small nut 2–4 mm. long, fully enclosed in a bladder-like involucre.
  • Small tree native to Europe.
  • Specimen is located in Hornbeam section, just past the Broadmoor service entrance on Foster Island Road.

5)  Styrax japonicus  (Japanese Silverbell)

  • The fruit is an oblong dry drupe, smooth and lacking ribs or narrow wings, unlike the fruit of the related snowdrop trees (Halesia) and epaulette trees.
  • Mature specimens may be found half-way down Azalea Way on the west side.
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