Rare Species Guide

  Basis for Listing

Although Lysimachia quadrifolia is a common woodland plant in parts of the eastern United States, it was completely overlooked in Minnesota until 1980 when it was found for the first time during a floristic survey of St. Croix State Park (Ownbey and Smith 1988). That discovery prompted further searches of appropriate forest habitat, and by 2012 approximately 14 additional sites had been found. However, all of the sites are confined to the eastern edge of Pine and Chisago counties, and all are in potentially sensitive and heavily exploited forest habitats. Effects of various forest management objectives on L. quadrifolia are unknown at this time. Given its rarity and limited geographic distribution, L. quadrifolia was listed as a special concern species in Minnesota in 1996.

  Description

The stems of L. quadrifolia are erect, 30-100 cm (11.8-39.4 in.) tall, usually sparsely hairy at the nodes, and they arise from slender rhizomes. The leaves are arranged in whorls of 4 (typically), and are sessile or on short petioles. The leaf blades are elliptic to lanceolate or ovate in outline, 3-12 cm (1.2-4.7 in.) long, and 0.8-3.5 cm (0.3-1.4 in.) wide. The base of the blade is wedge-shaped or rounded, the margins are entire, the tip is acute or acuminate, and the surfaces are densely to sparsely dotted with small pits (punctae) and hairy on the under sides. The flowers are on long, slender pedicels 1.5-3 cm (0.6-1.2 in.) long and are solitary in the axils of the leaves. The flowers have 5 petals, which are yellow with dark lines and reddish bases, and they are 5-8 mm (0.20-0.31 in.) long (Cholewa 2009).

Lysimachia quadrifolia can be distinguished from the other yellow-flowered Lysimachia that occur in Minnesota by the fact that its leaves occur in whorls of 4 and its flowers are on long pedicels that emerge singly from the axil of a leaf.

  Habitat

In Minnesota, L. quadrifolia occurs in a variety of mesic and dry-mesic forest habitats in association with a variety of coniferous and broadleaf tree species. These are typically mature forests, though not all are old-growth. The only obvious commonalities are relatively good, untrammeled forest soil, a relatively extensive forest canopy, and proximity to the St. Croix River valley.

  Biology / Life History

Lysimachia quadrifolia is a forest perennial that produces insect-pollinated flowers for sexual reproduction, which results in genetically distinct offspring called genets. It also produces underground rhizomes for vegetative reproduction, which results in genetically identical offspring called ramets. The proportion of ramets to genets in a typical population is not known.

Although the rhizomes are capable of extensive growth, one study reported that, in most cases, the rhizomatous connections between plants disintegrated quickly and were not maintained between above-ground stems (McCall and Primack 1985). The seeds do not posses any specialized dispersal mechanism, and presumably fall to the ground near the parent plant where they germinate the following spring.

  Conservation / Management

Knowledge of how L. quadrifolia responds to various forest management practices would be quite valuable, but is largely unavailable. One study in North Carolina found that L. quadrifolia survived for at least four years in a clearcut, but acknowledged that long-term effects are unknown (Horn 1980). It is also unknown if conditions in Minnesota might produce results that are different from North Carolina.

Closer to home, a fire study in northwestern Wisconsin found that L. quadrifolia decreased in oak savannas that were burned in the spring repeatedly over a 15 year period (Beck and Vogl 1972). This could have some relevance because most occurrences in Minnesota are in St. Croix State Park where management plans are attempting to increase the number and frequency of prescribed burns. The purpose of the burning is to encourage the development of savanna vegetation and prevent the expansion of forest and woodland vegetation. While often desirable, this could work against the survival of L. quadrifolia.

  Best Time to Search

The best time to search for Lysimachia quadrifolia is when it is in flower or fruit, from June through mid-September.

  Conservation Efforts in Minnesota

Most of the occurrences of L. quadrifolia in Minnesota are within St. Croix or Wild River state parks, where the species is protected from most forms of land development. However, as noted above, it may be vulnerable to conflicting vegetation management objectives.

  References and Additional Information

Beck, A. M., and R. J. Vogl. 1972. The effects of spring burning on rodent populations in a brush prairie savanna. Journal of Mammalogy 53(2):336-346.

Cholewa, A. F. 2009. Lysimachia. Pages 308-318 in Flora of North America Editorial Committee, editors. Flora of North America north of Mexico. Volume 8. Oxford University Press, New York, New York.

Horn, J. C. 1980. Short-term changes in vegetation after clearcutting in the southern Appalachians. Castanea 45(2):88-96.

McCall, C., and R. B. Primack. 1985. Effects of pollen and nitrogen availability on reproduction in a woodland herb, Lysimachia quadrifolia. Oecologia 67:403-410.

Ownbey, G. B., and W. R. Smith. 1988. New and noteworthy plant records for Minnesota. Rhodora 90:369-377.