Lab 9: Elms, Mulberries, and Legumes


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Plants to key out (and learn):
61. Ceanothus americanus (Rhamnaceae) 'New Jersey Tea'
New Jersey Tea was widely used by early American colonists as a remedy for bronchitis, whooping cough and asthma, as well as a substitute for Chinese teas after the Boston Tea Party. For this reason it is sometimes referred to as 'Revolutionary tea.'
Like a number of families that you are looking at this week, this plant is a nitrogen fixer.

62. Lupinus perennis (Fabaceae) 'Wild lupine'
This is the only species of Lupine native to Wisconsin. It has palmately compound leaves, and its stamens are monadelphous – the filaments of all ten are fused into a tube. Compare this to #63, which is diadelphous. The endangered Karner Blue butterfly relies on this species exclusively at certain points in its life cycle.
The species is restricted to sandy oak savannas. A relative of our native species is the Texas bluebonnet, L. texensis, the state flower of Texas.

63. Robinia pseudoacacia (Fabaceae) 'Black locust'
This tree is native farther south in the U.S. but has been introduced to most states in the nation. It becomes invasive in oak woodlands of the midwest. You can see standing trunks of black locusts in the Arboretum's Noe Woods, as well as Muir Woods. Recognize the species in winter by the unusual sinuous pattern of its bark ridges.

Learn more about all aspects of the plant, friends!


Species to learn:
64. Rosa multiflora (Rosaceae) 'Multiflora rose'
Invasive (see fact sheet) in much of the country, introduced from Japan as rootstock for cultivated roses. Notice the leaves, characteristic of this genus: pinnately compound with very prominent stipules, lflts finely toothed. Also note that the flowers have only five petals. This is the natural condition in roses. The "hips" are high in vitamin C.

65. Morus alba (Moraceae) 'White mulberry'
Also introduced from Asia, this tree is a popular street tree the females of which produce dark fruits. These are tasty but stain your laundry if you hang it to dry in the wrong place. Leaves lobed or unlobed.

Plant photos

66. Ulmus americana (Ulmaceae) 'American elm'
This majestic native forest tree was once planted as a street tree throughout the eastern U.S., but the introduction of the fungal Dutch Elm Disease has wiped out most of our large American elms. The enormous individuals that line the walks leading up and down Bascom Hill are kept alive by intravenous fungicide application. See Michigan Trees for useful characters to this and the similar U. rubra (slippery elm).

More info on American elm...


Genera to learn:
67. Cannabis (Cannabaceae) 'Hemp' or 'Marijuana' plus many other common names
Formerly considered a member of the Moraceae, this genus contains the species used to make hemp rope and fabrics and the species (same?) used to obtain THC - the active ingredient in marijuana. Also has medicinal qualities.
The other member of the family is Humulus, hops, used in brewing beer.

68. Geum (Rosaceae) 'Avens'
These are generally innocuous herbs of forests and woodland edges, spreading like mad along trails. This is presumably due to the hooks at the ends of the styles, which serve in seed dispersal on animal hair or people sweaters. Some species, though, e.g. prairie smoke, are very lovely and grow in open, higher quality habitat. The basal leaves of some species are evergreen. The prior year's dark green leaves lie flat on the ground and die off some time after the new leaves begin to grow, but they presumably provide some energy to the plant early in the spring.

69. Rhamnus (Rhamnaceae) 'Buckthorn'
An all-to-common noxious invader. The round, toothed leaves (oppositely arranged) and blackish bark are distinguishing features of this large shrub or small tree. It holds its leaves (which stay green) well into the fall. Small flowers are followed by black berries.

70. Trifolium (Fabaceae) 'Clover'
All eight of our species are native to Europe and the Mediterranian region and introduced in the U.S. They are cultivated as "green manure" in crop rotation and as forage crops. The leaves can be used to make a dark tea, but care should be taken not to use them from yards or fields that have been sprayed.