Ulmus rubra Muhl.
slippery elm
Researcher: Tanner Filyaw

Common Names:
Red Elm
Gray Elm
Soft Elm
Moose Elm
Indian Elm (21)
Sweet Elm
Winged Elm (95)

Genus: Ulmus (21), contains 14 species (8)

Family: Ulmaceae (22), and contains 5
genera with 28 official taxa (8)

Synonyms:
Ulmus fulva (Michx) (8)
Ulmus crispa Willd. 1809
Ulmus dimidiata Raf. 1838
Ulmus pendula Willd. 1796
Ulmus pinguis Raf. 1817 (51)
Ulmus pubescens Walter (10)

Relatives:
Ulmus alata Michx. -- Winged elm   
Ulmus americana L. -- American elm 
Ulmus crassifolia Nutt. -- Cedar elm 
Ulmus davidiana Planch. -- Japanese elm
Ulmus glabra Huds. -- Wych elm 
Ulmus ×hollandica Mill. -- Dutch elm  
Ulmus ×notha Wilhelm & G. Ware, hyb.
nov. ined.  
Ulmus parvifolia Jacq. -- Chinese elm  
Ulmus procera Salisb. -- English elm  
Ulmus pumila L. -- Siberian elm 
Ulmus serotina Sarg. -- September elm 
Ulmus thomasii Sarg. -- Rock elm  
Ulmus villosa Brandis ex Gamble --Cherry-bark elm (8)

Duration: The slippery elm is a perennial
species that can be very long lived. 
There have been documented cases of individuals reaching 200 years old, which is longer   than normal for a medium-sized
tree (93).

Habit: Small to medium sized deciduous tree with a broad crown (4).

Height: Reaches an average height of 
60-70 feet, but can reach up to 130 feet
tall on the best sites (21).



c) 2002 Steven J. Baskauf - Terms of use

Stems: The trunk exhibits straight growth
and has an average measurement of
 24-36 inches d.b.h.  The bark is light
brown to grayish in color and has a
 rough, fissured texture (22).


Slippery Elm Leaves
http://www.domtar.com/arbre/english/p_orrou.htm

Leaves: Leaves are alternate and simple
with a doubly serrate margin. They are
roughly 4-6 inches long, and 2-3 inches wide.
The most distinguishing characteristics are
an in-equilateral leaf base, elongated narrow
tip, and they have a rough sand papery
feel (110).


(c) 2003 Steven J. Baskauf - Terms of use

Flowers: The flowers of slippery elm are
monecious, meaning they are either male or female,
with both sexes of flowers produced
on the same plant.The flowers are small
and light green in color, and occur in cluster
of 3 or 5 (22).  Blooms can be start as early
as February, and can last into May (21).



Slippery Elm Fruit
http://www.domtar.com/arbre/english/p_orrou.htm

Fruit: The fruit/seed of U. rubra is a papery samara measuring about ¾-1 inch across (22), which tends to be larger than most native
elm species (93). The seeds begin to reach maturity between April and June, and then
disperse by wind, water, or gravity (21).
Seed production with the slippery elm can fluctuate from time to time, with large seed
crops being produced every 2-4 years after
the individual has reach 15 years of age (93).

Roots: Slippery elm typically has a shallow
and widespread root system, and these root stocks are often used to propagate hybrid
elms (93).

Bud – Buds are dense and covered in
a fine downy hair that is yellowish in appearance (7).



(c) 2002 Steven J. Baskauf - Terms of use

Twig – Twigs are ash gray to brown gray, has rough sandpapery texture, and
mottled (spotted) (22).

Pollination: As with most tree species U. rubra is wind pollinated (4).

Habitat: Slippery elm is most commonly found growing near stream banks and
bottom lands with moist rich soils (21).  These soils are typically of the orders
Mollisol or Alfisol, but can be found
growing on much drier sites as well (93). Ulmus rubra is highly adapted to moist conditions, and can even persist in areas
that remain inundated for 2 to 3 months
at a time (93).  Despite this adaptation it
has been documented that the species
will not reproduce under constantly
flooded conditions (21).

Associations: Ulmus rubra is found growing in association with more than 60 deciduous
 species which include:

Hickories – (Carya ovata, C. cordiformis, C. tomentosa, and C. glabra)
Oaks – (Quercus macrocarpa, Q. muehlenbergii, Q. alba, Q. velutina, and Q. rubra)
Box Elder - (Acer negundo)
Black Gum – (Nyssa sylvatica)
Hackberry – (Celtis occidentalis)
Honey Locust – (Gleditsia triacanthos)
Basswood – (Tilia americana)
White Ash – (Fraxinus americana)
Blackberry – (Rubus allegheniensis)
Black Raspberry (Rubus occidentalis)
Bittersweet - (Celastrus scandens)
Virginia Creeper – (Parthenocissus quinquefolia)
Wild Grape – (Vitis spp.)
Blackhaw –(Viburnum  prunifolium)
Hydrangea – (Hydrangea arborescens) (93)

Native Range: Native to Eastern North America (22).

Pests/diseases:
Dutch Elm disease - caused by
Ceratocystis ulmi (21)
Elm phloem necrosis
Elm leaf beetle - (Pyrrhalta luteola),
Larger elm leaf beetle - (Monocesta coryli),
Fall cankerworm - (Alsophila pometaria),
Spring cankerworm - (Paleacrita vernata)
Elm sawfly - (Cimbex americana),
European elm scale - (Gossyparia spuria)
Elm scurfy scale - (Chionaspis americana),
Elm leaf aphid - (Tinocallis ulmifolii),
Woolly apple aphid - (Eriosoma lanigerum) (93)

Other threats: Over-harvested in the wild for its bark (4), as well as occasional bark
stripping by deer (21).

History/culture:Both Native Americans
and early European settlers have long
used the slippery elm.  At on point in time
the bark of the plant was officially listed as
an approved drug in the U.S.
Pharmacopoeia until 1960, and was an ingredient in many over the counter products (7).  Ulmus rubra remained a popular ingredient until Dutch Elm disease, which is caused by the fungus Ceratocystis ulmi, nearly eliminated the species (95).  
It has also been documented that during
the Revolutionary War, George Washington’s’ troops survived for a
period of 12 days at Valley Forge on
slippery elm porridge (98).



http://world.std.com/~pgw/Deadball/slippery.html
tin, Slippery Elm Lozenges, 1885-1900
Henry Thayer & Co, Mfg. Cambridgeport MA, established 1847-Courtesy of the Smithsonian Institution

During the "deadball era" of American baseball, the 1900s and 1910s, slippery elm was commonly used to produce the right spit for a good "spitball" pitch. In 1920, the spitball pitch was banned for everyone but 17 "Grandfathers", registered major-league spitball pitchers, who were permitted to use the pitch indefinitely. "Outlaws" continued to throw the spitball pitch, probably less often than the legal spitballists did, usually without revealing any methods until retirement, if then.