Whorled Loosestrife grows upwards of 2 to 3 feet high, the stem rarely branched, and with fine hair.
The leaves, without teeth (entire) are in a whorl of 4 or 5, hence the common name. Leaves are sessile or on a very short stalk. Tips are pointed, bases are wedge shaped or rounded, the underside has more hair than the upper side and the upper side has a series of fine pits. Leaf margins have hair.
The inflorescence is a whorl of solitary long-stalked flowers rising singly from the leaf axils along the upper stem.
The flowers are five-parted with a yellow corolla that is either dark-spotted or with darker streaks. The petal are pointed to slightly rounded and the edges are also streaked. There are five stamens which are united at the base by a reddish fleshy band that is attached to the petals, thus giving them the appearance of an upright tube surrounding the style; they separate only at the anthers which are reddish. The length of the stamen filaments is shorter than the corolla. The calyx is very short with five green lanceolate sepals streaked with black or maroon resin canals and covered with fine hair, some of which is short glandular hair.
Seed: Fertile flowers produce a smooth seed capsule, 3 - 3.5 mm long, almost as long as the sepals. Dispersion is by simply dropping to the ground.
Habitat: The plant grows in large numbers in the Upland Garden, particularly on Aspen Alley. It grows from a slender rhizome and can spread vegetatively that way. It is adapted to dry to mesic sunny areas in clearings, fields, meadows and is also found in the understory of the forest.
Names: Whorled Loosestrife was formerly slotted into the Primrose family (Primulaceae), but the change to Myrsine is explained at the page bottom. The genus name, Lysimachia, is from the Greek for either king Lysimachus or from lysis meaning "a release from" and mache is for "strife". The legend is that Lysimachus, king of Sicily, was walking through a field. A bull chased him. He grabbed a loosestrife plant, waved it in front of the bull and it calmed the bull. In general then, both the common and the generic name refers to a supposed power to soothe animals or "loose" them of their "strife". See below for more. The species name quadrifolia means 4-leaved. See notes below as to the uniqueness of the Garden Population.
The author name for the plant classification from 1753 - 'L.' refers to Carl Linnaeus (1707-1778), Swedish botanist and the developer of the binomial nomenclature of modern taxonomy. In 1803 Andre Michaux renamed the species Lysimachia hirsuta. Slightly later Rafinesque put it into the genus Steironema with the species name verticillatum but those names are no longer accepted.
Comparisons: A close relative that grows in the woodland is Fringed Loosestrife, Lysimachia ciliata L., where the leaves are not in a whorl and the flower corolla is slightly different. The Prairie Loosestrife, L. quadriflora, has the flowers in a whorl and the leaves are very narrow and linear.
Above: The long-stalked flowers have a yellow corolla that is either spotted or with darker streaks. The petal edges are pointed to slightly rounded and are also streaked. The five stamens are united at the base by a fleshy band that is attached to the petals.
Below: 1st photo - The narrow, linear sepals are streaked with maroon resin channels. Leaves: Both surfaces of the leaves have fine hair, more so on the underside ribs and on the leaf edges. The upper side (2nd photo) has fine pits, which show up better when viewed from the underside (3rd photo photo).
Below: The leaf and flower whorl typical of the plant. Note the hairy stem.
Notes: Whorled Loosestrife is not indigenous to the Garden. Eloise Butler introduced it to the Garden area on April 26, 1913 with plants sourced from Kelsey's Nursery in North Carolina. The next notations in her log raise a question as to source. In 1915 she wrote she discovered it in bloom and it had been introduced in sod with another plant acquired from Eagle Creek near Savage. In 1919 she noted planting 2 plants she got from a meadow near the golf links of Glenwood Park. More were added in 1925, '29 and '30, but all from sources in Wisconsin.
Questions: Whorled Loosestrife is considered native to Minnesota but in opposition to Eloise Butler's notes, it has been found in Minnesota only in Pine County. Did she mis-identify it? or was it growing in those places in her day and no collections had ever been made? The Minnesota DNR states the species was found in Pine County only in 1980 and since then about 13 additional sites have been found, all in Pine County and most are in St. Croix State Park, somewhat protected. The last specimen collected for the University Herbarium was in the year 2000. The plant is listed on the State's "Special Concern" plant list. Per the DNR "A species is considered a species of special concern if, although the species is not endangered or threatened, it is extremely uncommon in Minnesota, or has unique or highly specific habitat requirements and deserves careful monitoring of its status." Thus, the population in the Eloise Butler Wildflower Garden is very special. It is much more prevalent in Wisconsin. Minnesota is at the extreme western edge of the plants range. It is found eastward from here to the coast, both in the U.S. and in Canada. Martha Crone listed it on her 1951 census but with the now unaccepted name of Steironema verticillatum and it has been in the Garden on all later census reports.
Fourteen species of Lysimachia are of record in Minnesota per the U of M Herbarium as of 2018; several have not been collected in recent decades. Ten are still listed currently by the DNR on their plant surveys. Of those nine are native, one is introduced. The species of Lysimachia of record in the Garden, current and historical, are: Starflower, L. borealis; Fringed Loosestrife, Lysimachia ciliata; Moneywort, L. nummularia (the introduced species); Prairie Loosestrife, Lysimachia quadriflora; Whorled Loosestrife, L. quadrifolia; Swamp Candles, Lysimachia terrestis; Tufted Loosestrife, Lysimachia thyrsiflora; Garden Loosestrife, Lysimachia vulgaris.
Family Change: Some of the leading references have moved the species of Lysimachia from the Primrose (Primulaceae) family into the Myrsinaceae plant family following the lead of Flora of North America (FNA) (Ref. #W7). The U of M Checklist of the Vascular Flora of Minnesota (Ref.#28C) follows this classification. FNA states: “M. Källersjö et al. (2000) and B. Ståhl and A. A. Anderberg (2004) removed the nonrosette terrestrial members from Primulaceae in the broad sense and placed them in the Myrsinaceae, which are further distinguished by leaves and calyx often dotted with yellow or dark streaks, flowers with relatively shorter corolla tubes, seeds immersed in placentae, and wood devoid of rays or with multiseriate rays only.”
Lore: As explained above, the common perception that a loosestrife plant has soothing powers over animals led people to tie a branch to the yolk of oxen, making them easier to handle. The plant is known to repel gnats and other irritating insects which maybe explains why the animals were easier to handle. Pliny the elder wrote that the odor of loosestrife would keep snakes away.
References: Plant characteristics are generally from sources 1A, 32, W2, W3, W7 & W8 plus others as specifically applied. Distribution principally from W1, W2 and 28C. Planting history generally from 1, 4 & 4a. Other sources by specific reference. See Reference List for details.
Identification booklet for most of the flowering forbs and small flowering shrubs of the Eloise Butler Wildflower Garden. Details Here.
Friends of the Wild Flower Garden, Inc. Text and photos are by G. D. Bebeau unless otherwise credited. "www.friendsofthewildflowergarden.org"