Details for: PI 635109, Ulmus americana L., 'Jefferson'

Summary Data

Taxonomy:

Ulmus americana L.

Cultivar:

'Jefferson'

Origin:

Developed – Maryland, United States

Maintained:

North Central Regional Plant Introduction Station

Received by NPGS:

08 Sep 2004

Improvement Status:

Cultivar

Form Received:

Plant

Life Cycle:

Perennial

Life Habit:

Tree

Availability

This accession is not available. Contact site for status.

North Central Regional Plant Introduction Station

Please include a note with your order if material other than cuttings (default option) is desired (e.g., leaf tissue). REQUESTS FOR LIVE PROPAGULES SUCH AS CUTTINGS AND SCIONS WILL BE CANCELLED UNLESS ACCOMPANIED BY SPECIAL INSTRUCTIONS SPECIFYING A DESIRED TIMEFRAME FOR SHIPPING.

There are no images for this accession.

Core Passport Data

Taxonomy:

Ulmus americana L.

Cultivar:

'Jefferson'

Origin:

Developed – Maryland, United States

Maintained:

North Central Regional Plant Introduction Station

Received by NPGS:

08 Sep 2004

Improvement Status:

Cultivar

Form Received:

Plant

Life Cycle:

Perennial

Life Habit:

Tree

Source History

Developed

Maryland, United States

Developer(s):

Townsend, A.M., U.S. National Arboretum

Donated

08 September 2004.
District of Columbia, United States

Donor(s):

Townsend, A.M., U.S. National Arboretum

Accession Names and Identifiers

'Jefferson'

Type: Cultivar name

NA 62001

Type: Institute identifier

Group: NA

U.S. National Arboretum

NPS 3-487

Type: Other or unclassified name

Narrative

Selected from approximately 600 elms planted on the National Mall in Washington D.C. Triploid selection released jointly by the U.S. National Arboretum and the National Park Service in 2004 because of its disease tolerance and exceptional horticultural characteristics. In experiments conducted in the District of Columbia and at Glenn Dale, Maryland, rooted cuttings have demonstrated high levels of tolerance to both species of the fungus which causes Dutch elm disease. Tolerance of this clone to Dutch elm disease is characterized by a significantly lower extent of foliar symptoms and crown dieback after fungal inoculation, compared to other American elm selections and seedlings. Although not completely immune to the disease, it has an unusually high level of disease tolerance and will contribute to the diversity of elm selections now becoming available in the nursery and landscape industries. A diversity of American elm cultivars will help sustain the species as it begins to regain its stature in the urban forest. Distinguished by dark green leaves which develop earlier in the spring and are retained later in the fall than surrounding American elms. The parent tree is approximately 70 years old (90 cm DBH, 20.6 m tall) and has an expansive umbrella-shaped crown. Branch unions are broad and U-shaped compared to the narrow V unions often found in other American elm trees. The bark is smooth, light to reddish gray in young trees becoming dark gray and fissured in older trees. Summer leaves average 106 mm long by 59 mm wide and are dark green, turning yellow in the autumn. In adaptability trials, it has grown well in the District of Columbia, Maryland, Minnesota, Missouri, New Jersey, Oklahoma, Oregon, and Tennessee, and can be considered adaptable from USDA Zones 4 through 7. Readily propagated by softwood cuttings. Using conventional techniques, 90% of the cuttings collected in mid-May in the District of Columbia usually root within 10 weeks. Excellent choice for planting in urban and suburban sites, large yards, and recreational and industrial parks. It will make a good street tree where there is a wide tree lawn, and where a high arching effect is desired. Its combination of Dutch elm disease tolerance, widespread adaptability, and umbrella-shaped crown will fill important needs of the American public.

Ulmus americana L.

Genus:

Ulmus

Subgenus:

Oreoptelea

Section:

Blepharocarpus

Family:

Ulmaceae

Nomen number:

40817

Place of publication:

Sp. pl. 1:226. 1753

Typification:

View in Linnean Typification Project

Verified:

11/06/2002 by ARS Systematic Botanists.

Other conspecific taxa

Autonyms (not in current use), synonyms and invalid designations

Common names

Language	Name	seq	Citation
English	American elm	1	Wiersema, J. H. & B. León. 1999. World economic plants: a standard reference CRC Press, Boca Raton, FL.
English	water elm	1	Huxley, A., ed. 1992. The new Royal Horticultural Society dictionary of gardening
English	white elm	1	Wiegrefe, S. 1997. pers. comm. Note: re. common names
French	orme d'Amérique	2	FNA Editorial Committee. 1993-. Flora of North America.
German	amerikanische Ulme	2	Erhardt, W. et al. 2002. Zander: Handwörterbuch der Pflanzennamen, 17. Auflage
German	Weißulme	2	Encke, F. et al. 1993. Zander: Handwörterbuch der Pflanzennamen, 14. Auflage
Italian	olmo americano	2	International Seed Testing Association. 1971. A Multilingual Glossary of Common Plant-Names 2. Trees.
Swedish	amerikansk alm	2	Aldén, B., S. Ryman, & M. Hjertson. 2012. Svensk Kulturväxtdatabas, SKUD (Swedish Cultivated and Utility Plants Database; online resource)

Annotations

Observations

Phenotype Data

Category	Descriptor	Description	Value	Study	Availability
CYTOLOGIC	PLOIDY	Ploidy level determined either through flow cytometry or chromosome counting.	TRIPLOID - Triploid.	PLOIDY	Not Available
DISEASE	DED CROWN SYMPTOMS 1 YPI	Average percent of the tree's crown displaying symptoms (e.g. defoliation, dieback, wilting or death) in a field setting one year post inoculation with Ophiostoma novo-ulmi and/or O. ulmi spore suspensions.	1	DED CROWN SYMPTOMS - TOWNSEND ET AL 2005	Not Available
DISEASE	DED CROWN SYMPTOMS 2 YPI	Average percent of the tree's crown displaying symptoms (e.g. defoliation, dieback, wilting or death) in a field setting two years post inoculation with Ophiostoma novo-ulmi and/or O. ulmi spore suspensions.	0	DED CROWN SYMPTOMS - TOWNSEND ET AL 2005	Not Available
DISEASE	DED CROWN SYMPTOMS 28 DPI	Average percent of the tree's crown displaying symptoms (e.g. defoliation, dieback, wilting or death) in a field setting 28 days post inoculation with Ophiostoma novo-ulmi and/or O. ulmi spore suspensions.	0	DED CROWN SYMPTOMS - TOWNSEND ET AL 2005	Not Available
INSECT	JAPANESE BEETLE FEEDING -LAB	Percent leaf tissue removed by adult female Japanese beetles feeding on Ulmus in no-choice (NC) feeding studies. Average of ten replicates per tree with one to three trees tested per accession.	48	JAPANESE BEETLE FEEDING - LAB	Not Available
INSECT	JAPANESE BEETLE FEEDING -FIELD	Percent defoliation by adult female Japanese beetles feeding on Ulmus in a field setting. Average of three to five trees per accession.	18	JAPANESE BEETLE FEEDING - FIELD	Not Available
INSECT	JAPANESE BEETLE EGGS LAID	Fecundity (total eggs laid) of adult female Japanese beetles ovipositing when feeding on Ulmus leaves. Average of ten replicates per tree with three trees tested per accession.	1	JAPANESE BEETLE FECUNDITY	Not Available
INSECT	OVERALL INSECT RESISTANCE	Composite score of resistance to four major and eight minor insect pests. Low values indicate resistance and high values indicate susceptibility. Details provided in Methods section and in cited publication.	29	OVERALL INSECT RESISTANCE	Not Available
INSECT	ELM LEAF BEETLE FEEDING	Percent defoliation by elm leaf beetles on 15-cm-long shoots that were randomly selected from the north, south, east, and west quadrants of each tree growing under field conditions. Average of five to ten trees scored over the course of one to six years.	25.4	ELM LEAF BEETLE FEEDING	Not Available
INSECT	ELM LEAF BEETLE LARVAE - LAB	Number of days elm leaf beetle larvae survived on elm leaves in lab bioassay. Average of three replicates.	7	ELM LEAF BEETLE LARVAE - LAB	Not Available
INSECT	ELM LEAF BEETLE ADULTS - LAB	Percent emergence of elm leaf beetle adults from larvae feeding on elm leaves in lab bioassay. Average of three replicates.	10	ELM LEAF BEETLE ADULTS - LAB	Not Available
INSECT	ELM LEAF BEETLE EGGS - LAB	Number of eggs laid per elm leaf beetle adult female on elm leaves in lab bioassay. Average of three replicates.	0	ELM LEAF BEETLE EGGS - LAB	Not Available
MORPHOLOGY	LEAF AREA	Leaf surface area in square centimeters; average of 20 leaves.	29	LEAF AREA	Not Available
MORPHOLOGY	LEAVES PER SHOOT	Number of leaves on the terminal 30 cm of new growth (measured spring 2009); average of ten shoots.	13	LEAVES PER SHOOT	Not Available
MORPHOLOGY	ADAXIAL LEAF PUBESCENCE	Leaf pubescence was characterized by examining upper (adaxial) leaf surfaces of leaves from each tree with a binocular microscope. Trichome density was subjectively rated as 0, 1, 2, 3, or 4 corresponding to glabrous (few or none), light, moderate, dense, or very dense, respectively. Twenty leaves analyzed.	1 - Light.	LEAF PUBESCENCE	Not Available
MORPHOLOGY	ABAXIAL LEAF PUBESCENCE	Leaf pubescence was characterized by examining lower (abaxial) leaf surfaces of leaves from each tree with a binocular microscope. Trichome density was subjectively rated as 0, 1, 2, 3, or 4 corresponding to glabrous (few or none), light, moderate, dense, or very dense, respectively. Twenty leaves analyzed.	3 - Dense.	LEAF PUBESCENCE	Not Available