|
| |
Ulmus wilsoniana
'Prospector'
|
The U.S. National Arboretum presents Ulmus
wilsoniana 'Prospector',
an elm of Asian origin with proven pest and Dutch elm disease
resistance. 'Prospector' offers the
vase shape, dense crown, and large green leaves of its American cousin
but in a smaller package. It is a great choice for spaces that need an
American elm but aren’t quite large enough. Try 'Prospector' as a street
tree, under power lines, in municipal sites or parks, and, of course, at
home.
 |
| 'Prospector',
left; American elm, right |
|
|
'Frontier'
Hybrid Elm
|
| Botanical Name: |
Ulmus wilsoniana Schneid. 'Prospector'
(NA 55398; PI 536050) |
| Family: |
Ulmaceae |
| Hardiness: |
U.S.D.A. Zones (4)5–7 |
| Development: |
'Prospector' elm was initially selected by
A.M. Townsend and L.R. Schrieber in 1975 from a 1965 planting of U.
wilsoniana seedlings in Delaware, Ohio. Over the next 15 years, this
plant demonstrated a high level of resistance in both laboratory and
field trials to the fungus that causes Dutch elm disease (DED) and to
elm leaf beetle. 'Prospector' was named and released in May, 1990. |
| Significance: |
The Dutch elm disease epidemic of the 20th
century sparked a great interest in Asian elm species as potential
replacements for the American elm because of their inherent tolerance or
resistance to DED. The Chinese species, U. wilsoniana, which resembles a
small American elm in form and leaf, was an excellent prospect for
evaluation in DED trials. 'Prospector' is the first cultivar of U.
wilsoniana selected and released in the United States. It has
consistently exhibited superior tolerance to DED and elm leaf beetle. |
| Description: |
Height and Width:
Approximately 50 feet tall, 25 foot crown spread
at maturity. Smaller than American elm.
Growth Rate:
Moderately fast; 23 feet tall and 21 foot crown spread
at 10 years under normal nursery conditions. Vigorous.
Habit:
Deciduous tree with vase-shaped crown, similar to American
elm, but pendulous at much lower height; dense canopy.
Foliage:
Leaves 4 1/2 inches long, 3 1/3 inches wide, obovate. New
leaves emerge orange red and mature to green; good yellow fall color.
Bark: Light
grey.
Flowers: Very
early spring; inconspicuous; not ornamental.
Fruit: Small;
samaras emerge green, dry to brown; not weedy. |
| Culture: |
Grows best in well-drained soil. Tolerates
somewhat adverse sites. Successfully grown in Maryland,
California, Ohio, Oklahoma, Oregon, Tennessee, Virginia. Requires
regular pruning to maintain form due to vigorous early growth. |
| Propagation: |
Roots easily from softwood cuttings under
mist, 3000–8000 ppm IBA, in 3–4 weeks. |
| Landscape Use: |
Locations requiring small to
intermediate-sized shade tree: Parks, lawns, streets, or highways, under
power lines. |
| Availability: |
Limited availability from wholesale nurseries. |
|
U.S. National Arboretum Plant Introduction
Floral and Nursery Plants Research Unit
U.S. National Arboretum, U.S.
Department of Agriculture, Agricultural Research Service, 3501 New York
Ave., N.E., Washington, DC 20002 |
To visit the
U.S. National Arboretum website please follow this link.
Return to
New Cultivars
click here!
Return to
Nursery Stock
webpage click here!
|
