Washington D.C. is home to thousands of flowering cherry trees – a gift from Japan almost 100 years ago. The nation’s capital also is home to the U.S. National Arboretum, where researchers look for superior selections of the picturesque tree.
Margaret Pooler is acting research leader of the Floral and Nursery Plants Research Unit at the USNA, and one of her favorite plants to pollinate is the flowering cherry.
“Flowering cherries are physically very easy to pollinate due to the large flower size, single stigma and ease of removing anthers,” she said. “Plus it is very calming to stand under the cherry trees doing pollinations in early spring as the birds are singing and cherry blossoms drift down on you from the branches above. I also like the flowering cherries because there are so many new hybrids that can be made.”
Pooler and her team are charged with finding woody landscape plants that are disease and pest resistant, tolerant of various environmental stresses, have superior ornamental value and are non-invasive. Her emphasis is on flowering cherries, redbuds and crape myrtles.
Researchers at the USNA use seed propagation to grow out the new hybrids they create.
“After we make advanced selections and are ready to test plants in replicated field trials, we propagate mostly by softwood cuttings, under mist,” Pooler said. “Occasionally we run into a selection that is difficult to root from cuttings, in which case we bud it or enlist the help of a cooperating nursery to bud it for us.”
The USNA’s first redbud release in 2001 was Cercis chinensis ‘Don Egolf,’ a vividly colored cultivar that doesn’t produce seed. It was named for the late Donald Egolf, renowned shrub breeder at the USNA.
Egolf had the biggest influence on Pooler’s career at the arboretum, even though she never met the man.
“He left great records and a diversity of plant material, so I was able to continue where he left off and also expand the program with modern breeding technologies,” she said.
Other USNA releases include: Syringa ‘Old Glory’ and ‘Declaration’; Prunus ‘First Lady’ and ‘Dream Catcher’; Callicarpa dichomata ‘Duet’; Viburnum ‘Nantucket’; and Lagerstroemia ‘Arapaho,’ ‘Cheyenne’ and ‘Pocomoke.’ The arboretum also released a series of potted plants – Ornithagalum ‘Chesapeake Blaze,’ ‘Chesapeake Sunburst’ and ‘Chesapeake Sunset.’
From top left: Syringa ‘Betsy Ross’; a Viburnum ‘Nantucket’ flower; ‘Nantucket’s’ foliage, Redbud ‘Don Egolf’; and a full ‘Nantucket’ view. Photos: USNA
The author is editor of Nursery Management & Production.
Explore the July 2010 Issue
Check out more from this issue and find your next story to read.
