Fragrant sumac (Rhus aromatica var. aromatica) is common in eastern and central United States from Connecticut to Kansas south to Georgia and Texas. In is uncommon in the upper Midwest. It is native to Minnesota but has been recorded only in Goodhue and Winona Counties. It is sometimes used for stabilizing embankments. The low-growing cultivar Gro-Lo is sold as an ornamental shrub.
Fragrant sumac is found in prairie ravines, open hillsides, woodland edges and openings, and sand dunes. In April and May it produces small clusters or greenish-yellow flowers. In late summer these turn into clusters of hairy, bright red berry-like fruits. Stems and leaves, when crushed, have an odor which has been variously described as citrussy, pleasantly bittersweet, very unpleasant, and malodorous.
Fragrant sumac is easily distinguished by its leaves with only 3 leaflets. Smooth sumac and staghorn sumac both have leaves with 11 to 31 leaflets.
Lance-leaf fog-fruit (Phyla lanceolata) is common in its core range from Ohio to Kansas, much less common in Minnesota. It is found in wet to moist areas along streambanks, margins of ponds and lakes, marshes, and roadside ditches. From June to September it produces numerous small heads of many tiny flowers surrounding a purple cone.
The common name “fog-fruit” comes from an old Scottish word for moss, fog. It refers to the matted, moss-like habit of the plant. Another common name “frog-fruit” originated in what appears to be a typographical error in the 1834 book Botanical Teacher for North America. The error has persisted and is now the most commonly used name for this plant.
The flower heads of lance-leaf fog-fruit are distinctive. There are no similar species in Minnesota.
European bur-reed (Sparganium emersum) is a common plant in northern Minnesota. It is found in shallow water at the margins of lakes and swamps, in ponds and streams, and in backwaters of large rivers. From June to August it produces conspicuous, spherical heads of tiny white flowers.
The spongy leaves rising from the base of the plant may be stiff, erect, and up to 32″ long, or limp, floating, and up to 80″ long. The leaf-like bracts on the flowering stem are smaller and spread outwards or bend upwards.
There are 22 species of bur-reed worldwide, 9 in North America north of Mexico, 6 in Minnesota. European bur-reed is distinguished by its small size; leaves that are flat, not rounded, on the back; unbranched inflorescence with up to 6 pistillate heads; pistillate flowers with a single stigma; and spindle-shaped fruit that tapers to both ends.
When a flowering stem is not present the stiff leaves may be mistaken for narrow-leaved cattail. However, those leaves are rounded on the back, not flat.
Cypress spurge (Euphorbia cyparissias) is native to Europe and western Asia but not to North America. It was imported, cultivated as an ornamental, and sold in nurseries for use in gardens, parks, and graveyards. It escaped cultivation and is now naturalized across the United States and southern Canada. It is considered invasive and is on the state noxious weed list of 46 states including Wisconsin, but does not show up on any list of invasive or noxious species in Minnesota.
The latex exuded by broken stems and leaves of this plant causes a rash in some people similar to that of poison ivy. The plant may be also toxic to cattle and horses.
Cypress spurge is similar in appearance to another invasive plant, leafy spurge (Euphorbia esula). Cypress spurge is a much smaller plant with smaller, very crowded leaves.
Allegheny monkeyflower (Mimulus ringens var. ringens) is a plant of wet places. It is common in meadows, swamps, fens, and marshes, and is also found on streambanks, riverbanks, and in roadside ditches. Between June and August it produces solitary purplish-blue flowers from the axils of the upper leaves.
The genus name Mimulus, from the Greek mimos meaning “imitator”, and the common name “monkeyflower”, refer to red markings on the corolla of some of the yellow species which are said to resemble a monkey’s face.
Rattlesnake master (Eryngium yuccifolium var. yuccifolium) is a common plant of native tallgrass prairies in the eastern United States. Southeastern Minnesota is the northwest extent of its natural range, but very little tallgrass prairie remains in the state. This habitat loss led the Minnesota DNR to list it as a special concern species in 1984.
The common name is derived from its traditional use by Native Americans to treat rattlesnake bite. The plant was also used as a diuretic, a sedative, a pain reliever, a tonic, and for cordage.
This plant is easily identified. The waxy, bluish-green stem and foliage; stiff, grass-like leaves with widely scattered spiny or thread-like teeth; and white, spherical flower heads, combine to create a unique appearance. There are no similar species in Minnesota.
Gray birch (Betula populifolia) is native to eastern United States and Canada as far west as Illinois. It has been recorded in Minnesota only twice, once in Anoka County in 2013 and again in Itasca County in 2015. In its native range it is an early successional tree colonizing burned areas, abandoned pastures, road cuts, and other disturbed areas.
Gray birch is one of the smallest trees in the northeast, usually no more than 30′ tall and about 6″ in diameter at breast height. It is short-lived, seldom surviving more than 50 years. The resemblance of the leaves to those of quaking aspen (Populus deltoides) is the source of the species name populifolia.
Gray birch is easily identified by the aspen-like triangular leaves with flat bases and long, drawn-out tips. It is also distinguished by grayish-white bark that does not easily peel; dark triangular patches at the base of each branch and branch scar; and male catkins that occur individually, not in groups.
Rope dodder (Cuscuta glomerata) is an annual herbaceous vine that parasitizes the above-ground portion of other plants. It is considered a noxious weed in the United States and a restricted weed seed in Minnesota, but is listed as threatened in Florida and is a Special Concern species in Wisconsin.
In the spring a seed produces a single, slender, fast-growing stem, and a single root. The root is for anchoring only. It does not absorb nutrients and withers away after the stem attaches to a host plant. The stem lives solely on the nutrients stored in the embryo. It must find and attach to a host plant in 5 to 10 days or it will die. It seeks a compatible host by detecting and growing toward specific airborne volatile organic compounds. When it encounters another plant it wraps around it. If the plant is a suitable host the dodder stem will produce sucker-like, specialized roots (haustoria) that penetrate and draw nutrients from the host plant’s tissue. As it continues to grow it becomes more robust and climbs the host, twining in a counter-clockwise spiral.
From May to early July rope dodder looks like orange tangled string. In July it produces flowers on parts of the stem that are tightly appressed and attached to a host plant. The inflorescence is a dense, rope-like mass of tiny flowers wound spirally around the stem of the host.
There are at least 7 species of dodder in Minnesota. The dense, rope-like inflorescence distinguishes this from all other dodders.
Blackberry lily (Iris domestica) is a popular garden plant from Asia that has escaped cultivation in North America. It is now widespread in eastern and central United States but scattered and still uncommon. It has been recorded only twice in Minnesota: once, date unknown but prior to 1991, in Waseca, where it was planted and escaped cultivation; and once on 8/8/2014 in Baker Park Reserve in Hennepin County.
The common name of this plant is a misnomer. It is an iris, family Iridaceae, not a lily, family Liliaceae. It gets its name from the lily-like appearance of the flowers and the blackberry-like appearance of the seed clusters. It blooms from June to July and is typically found on hillsides, pastures, woodland openings, thickets, roadsides, old fields, old homesteads, and disturbed areas. The flowers bloom from dawn to dusk and last only a single day.
At different times in its development, blackberry lily is similar in appearance to some of our native lilies and irises. It is distinguished by a combination of the following characteristics: sword-like basal leaves; alternate, overlapping stem leaves; flowers held erect or horizontal, not hanging downward; sepals and petals widely spreading, not curved backward; and clusters of black seeds that look similar to blackberries.
Northern catalpa (Catalpa speciosa) is occasionally seen in suburban front yards but rarely seen in natural areas in Minnesota. That may soon change. Prior to European settlement the range of northern catalpa had contracted to a small area around the confluence of the Mississippi and Ohio Rivers. In the 1930s and 1940s it was widely planted as a windbreak and cultivated for fence posts in Ohio. It is still sold and planted as a shade tree and ornamental because of its large leaves and showy flowers. It has now become naturalized from Kansas to Virginia north to southern Michigan and southern Wisconsin. Its range continues to spread and now includes almost all states east of the Rocky Mountains. In Minnesota it is not fully established but is locally naturalized. It is hardy up to zone 4, which includes the southern half of the state.
Northern catalpa is a medium-sized, moderately fast-growing, moderately short-lived, deciduous tree. It has very large heart-shaped leaves arranged in whorls of three. From May to June it produces large, showy clusters of white flowers. The flowers are fragrant but inhaling their aroma may be poisonous to some individuals. The flowers are replaced in late summer by long, thin, pencil-shaped seedpods. In autumn the leaves turn pale yellowish-green and fall before turning yellowish-brown.
Chinese catalpa (Catalpa ovata) is also found in Minnesota. Northern catalpa is distinguished by unlobed leaves that are densely short-hairy on the underside, larger flowers, and relatively thick-walled seedpods.