Yellow marsh marigold (Caltha palustris var. palustris), also called common marsh marigold, is found throughout Minnesota except for the southwest corner of the state. It almost always occurs in wetlands. It is found in full or partial sun in woodlands and on meadows, marshes, and streambanks. The large, showy, yellow flowers appear in April and May.
Photo by Kirk Nelson
http://www.minnesotaseasons.com/Plants/yellow_marsh_marigold.html
Large yellow lady’s slipper (Cypripedium parviflorum var. pubescens), also called greater yellow lady’s slipper, is found throughout Minnesota except for the southwest corner of the state. In most of the state it occurs in moderate or deep shade in moderately moist upland forests. In the northwest corner of the state it occurs in full or partial sunlight in wet prairies and sedge meadows. The large showy flowers appear from May 10 to July 10, with peak blooming time June 5 to June 20 in the north and May 20 to June 1 in the south. Do not touch. The hairs on the stems and leaves cause dermatitis in some people.
http://www.minnesotaseasons.com/Plants/large_yellow_ladys_slipper.html
Photo by Bill Reynolds
Thimbleberry (Rubus parviflorus) is common in western North America but only isolated populations exist in the Great Lakes region. At one time its range may have been uninterrupted, only to be broken up by repeated glaciations and climate change.
The species name, parviflorus, means small flowered in Latin. That is an obvious misnomer since this plant has one of the largest flowers in the Rubus genus.
Photo by Bill Reynolds
White turtlehead (Chelone glabra) is an uncommon native perennial. It is found throughout the eastern half of Minnesota in wet meadows, open wet woodlands, sedge meadows, and marshes, often at the side of a stream. It is most easily recognized in July to September when it is topped with a spike of a few to many white flowers. The flowers are said to resemble the head of a turtle, giving this plant its common name.
The plant is highly variable and some authorities recognize up to eight subspecies.
http://www.minnesotaseasons.com/Plants/white_turtlehead.html
Photo by Bill Reynolds
Fireweed (Chamerion angustifolium) is a native, highly variable, widespread species. It is found throughout the circumboreal region of the globe including 43 states in the U.S. and every province of Canada.
Fireweed is a successional plant occurring in disturbed areas especially after a fire. It spreads aggressively by rhizome-like roots, often forming large colonies and becoming the dominant species.
The tight clusters or orange, dandelion-like flowers at the end of a leafless stem make orange hawkweed (Pilosella aurantiaca) an easily recognized plant. A native to northern and central Europe, it was introduced as an ornamental to Vermont before 1875. It has escaped cultivation many times and is now naturalized across the northern half of North America. It occurs in a wide variety of habitats and is especially suited to disturbed sites.
Orange hawkweed can form dense mats and crowd out native species. It is one of the six known pollen allelopathic plants. Pollen allelopathy occurs when the pollen of one species is transferred to another species. The transferred pollen then releases toxins which interfere with the growth of pollen tubes, the receptivity of the stigma or style, respiration, germination or growth of the seedling, production of chlorophyll in leaves, or production of seeds.
Though not controlled by the state, orange hawkweed is considered a noxious weed in Carlton, Cass, Itasca, and Koochiching Counties.
Photo by Bill Reynolds
The showy false whorls of yellow flowers and variegated leaves make yellow archangel (Lamiastrum galeobdolon) easy to identify. It is native to Europe and western Asia, where it is cultivated as an ornamental. It was imported into North America as a garden plant and has escaped cultivation. It has become naturalized in California and the northeast United States, where it is considered an invasive species. It is uncommon in Minnesota where, to date, it has been recorded only in St. Louis County.
http://www.minnesotaseasons.com/Plants/yellow_archangel.html
Photo by Bill Reynolds
There are only five known locations where western Jacob’s ladder (Polemonium occidentale ssp. lacustre) can be found today. Three of those locations are in Minnesota and two are in Wisconsin. The species is restricted to openings in conifer swamps that have a blanket of sphagnum and other mosses and are dominated by northern white cedar and sometimes tamarack and/or black spruce. It rises on a single erect stem. The leaves have up to 27 narrow leaflets that resemble a ladder. The blue flowers can be seen from late June to July.