Lupinus perennis
Encyclopedia
Lupinus perennis is a medicinal plant in the Fabaceae
family. It is widespread in the eastern part of the USA
(from Florida to Maine
), Canada (south of Ontario
), and on the coasts of the Arctic Ocean, where it grows on sand hills.
It derives only rosette-like radial leaves in the first year of vegetation. Stalks are numerous, erect, striated, slightly pubescent. Leaflets are obovate, with a blunted apex or pointed spear, naked from above, sparsely pubescent from below; their number is 7-11. Petiole
s are longer than leaflets; stipules are very small, almost missing.
The inflorescence
is long, sparsely flowered, sometimes almost verticilate. Flowers can range from blue to pink, but are most often blue or bluish purple. The calyx is silky, without bractlets; its upper labium with a protuberant basis, is integral or weakly emarginate, the lower one is integral, almost twice longer than upper. Floral bracts are styliform, shorter than the calyx, early falling. The corolla is purple or white, three times longer than the calyx. The vexillum
is shorter than the wings. The carina is weakly ciliate. Pods are yellow-grayish-brown, with straight lines, necklace-shaped, short and closely hirsute, easy shattered, with 5-6 seeds. Seed is oval with a light hilum
.
The Sundial Lupin is used as foodplants by the caterpillar
s of several lepidoptera
. Among these are the Frosted Elfin (Callophrys irus
) and the rare and endangered Karner Blue
(Lycaeides melissa samuelis), whose caterpillars feed only on Sundial Lupine leaves. Leaves that have been fed on by Karners have distinctive transparent areas where the larvae have selectively eaten only the green, fleshy parts.
Sundial lupine has been declining in number and range since the Industrial Revolution
. It is estimated that it has declined in number by about 90% since 1900. This decline has been deemed one of the primary causes of the Karner Blues' endangerment. The main causes of its decline are thought to be habitat loss, habitat fragmentation, and poor management. Currently it is threatened in Iowa
, Maryland
and New Hampshire
; it is endangered in Vermont
and may be extirpated in Maine
. Human development has eliminated a large portion of its viable habitat. Remaining habitat is often fragmented, which is problematic for the lupine because it limits the range over which it can reproduce. Viable sundial lupine habitat is often difficult to maintain because it flourishes after fires and other forms of disturbance. One reason this occurs is that sundial lupine seed coats are so tough that only pressure changes due to rapid heating or abrasion are strong enough to allow water to penetrate and start germination
. Moreover, fires, feeding by large ungulates, and mowing can improve habitat quality for established lupines by changing soil quality, vegetative structure, leaf litter depth. The exact mechanism for this is currently being investigated. Overall, the primary issue is that not enough habitat is burned or otherwise disturbed frequently enough to support the plant.
Fabaceae
The Fabaceae or Leguminosae, commonly known as the legume, pea, or bean family, is a large and economically important family of flowering plants. The group is the third largest land plant family, behind only the Orchidaceae and Asteraceae, with 730 genera and over 19,400 species...
family. It is widespread in the eastern part of the USA
East Coast of the United States
The East Coast of the United States, also known as the Eastern Seaboard, refers to the easternmost coastal states in the United States, which touch the Atlantic Ocean and stretch up to Canada. The term includes the U.S...
(from Florida to Maine
Maine
Maine is a state in the New England region of the northeastern United States, bordered by the Atlantic Ocean to the east and south, New Hampshire to the west, and the Canadian provinces of Quebec to the northwest and New Brunswick to the northeast. Maine is both the northernmost and easternmost...
), Canada (south of Ontario
Ontario
Ontario is a province of Canada, located in east-central Canada. It is Canada's most populous province and second largest in total area. It is home to the nation's most populous city, Toronto, and the nation's capital, Ottawa....
), and on the coasts of the Arctic Ocean, where it grows on sand hills.
It derives only rosette-like radial leaves in the first year of vegetation. Stalks are numerous, erect, striated, slightly pubescent. Leaflets are obovate, with a blunted apex or pointed spear, naked from above, sparsely pubescent from below; their number is 7-11. Petiole
Petiole (botany)
In botany, the petiole is the stalk attaching the leaf blade to the stem. The petiole usually has the same internal structure as the stem. Outgrowths appearing on each side of the petiole are called stipules. Leaves lacking a petiole are called sessile, or clasping when they partly surround the...
s are longer than leaflets; stipules are very small, almost missing.
The inflorescence
Inflorescence
An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Strictly, it is the part of the shoot of seed plants where flowers are formed and which is accordingly modified...
is long, sparsely flowered, sometimes almost verticilate. Flowers can range from blue to pink, but are most often blue or bluish purple. The calyx is silky, without bractlets; its upper labium with a protuberant basis, is integral or weakly emarginate, the lower one is integral, almost twice longer than upper. Floral bracts are styliform, shorter than the calyx, early falling. The corolla is purple or white, three times longer than the calyx. The vexillum
Vexillum
The vexillum was a flag-like object used in the Classical Era of the Roman Empire. The word is itself a diminutive for the Latin word, velum, sail, which confirms the historical evidence that vexilla were literally "little sails" i.e. flag-like standards...
is shorter than the wings. The carina is weakly ciliate. Pods are yellow-grayish-brown, with straight lines, necklace-shaped, short and closely hirsute, easy shattered, with 5-6 seeds. Seed is oval with a light hilum
Hilum (biology)
In botany, the hilum is a scar or mark left on a seed coat by the former attachment to the ovary wall or to the funiculus...
.
The Sundial Lupin is used as foodplants by the caterpillar
Caterpillar
Caterpillars are the larval form of members of the order Lepidoptera . They are mostly herbivorous in food habit, although some species are insectivorous. Caterpillars are voracious feeders and many of them are considered to be pests in agriculture...
s of several lepidoptera
Lepidoptera
Lepidoptera is a large order of insects that includes moths and butterflies . It is one of the most widespread and widely recognizable insect orders in the world, encompassing moths and the three superfamilies of butterflies, skipper butterflies, and moth-butterflies...
. Among these are the Frosted Elfin (Callophrys irus
Callophrys irus
The Frosted Elfin is a species of Lycaenidae that is native to North America.-Description:The wingspan ranges from , hindwings have one short tail. The top side of the wing is brown, males have long oval dark spots on the leading edge of their forewings...
) and the rare and endangered Karner Blue
Karner Blue
The Karner Blue, Lycaeides melissa samuelis, is a small, blue butterfly found in small areas of New Jersey, the Great Lakes region, southern New Hampshire, and the Capital District region of New York. The butterfly, whose lifecycle depends on the wild blue lupine flower , is classified as an...
(Lycaeides melissa samuelis), whose caterpillars feed only on Sundial Lupine leaves. Leaves that have been fed on by Karners have distinctive transparent areas where the larvae have selectively eaten only the green, fleshy parts.
Sundial lupine has been declining in number and range since the Industrial Revolution
Industrial Revolution
The Industrial Revolution was a period from the 18th to the 19th century where major changes in agriculture, manufacturing, mining, transportation, and technology had a profound effect on the social, economic and cultural conditions of the times...
. It is estimated that it has declined in number by about 90% since 1900. This decline has been deemed one of the primary causes of the Karner Blues' endangerment. The main causes of its decline are thought to be habitat loss, habitat fragmentation, and poor management. Currently it is threatened in Iowa
Iowa
Iowa is a state located in the Midwestern United States, an area often referred to as the "American Heartland". It derives its name from the Ioway people, one of the many American Indian tribes that occupied the state at the time of European exploration. Iowa was a part of the French colony of New...
, Maryland
Maryland
Maryland is a U.S. state located in the Mid Atlantic region of the United States, bordering Virginia, West Virginia, and the District of Columbia to its south and west; Pennsylvania to its north; and Delaware to its east...
and New Hampshire
New Hampshire
New Hampshire is a state in the New England region of the northeastern United States of America. The state was named after the southern English county of Hampshire. It is bordered by Massachusetts to the south, Vermont to the west, Maine and the Atlantic Ocean to the east, and the Canadian...
; it is endangered in Vermont
Vermont
Vermont is a state in the New England region of the northeastern United States of America. The state ranks 43rd in land area, , and 45th in total area. Its population according to the 2010 census, 630,337, is the second smallest in the country, larger only than Wyoming. It is the only New England...
and may be extirpated in Maine
Maine
Maine is a state in the New England region of the northeastern United States, bordered by the Atlantic Ocean to the east and south, New Hampshire to the west, and the Canadian provinces of Quebec to the northwest and New Brunswick to the northeast. Maine is both the northernmost and easternmost...
. Human development has eliminated a large portion of its viable habitat. Remaining habitat is often fragmented, which is problematic for the lupine because it limits the range over which it can reproduce. Viable sundial lupine habitat is often difficult to maintain because it flourishes after fires and other forms of disturbance. One reason this occurs is that sundial lupine seed coats are so tough that only pressure changes due to rapid heating or abrasion are strong enough to allow water to penetrate and start germination
Germination
Germination is the process in which a plant or fungus emerges from a seed or spore, respectively, and begins growth. The most common example of germination is the sprouting of a seedling from a seed of an angiosperm or gymnosperm. However the growth of a sporeling from a spore, for example the...
. Moreover, fires, feeding by large ungulates, and mowing can improve habitat quality for established lupines by changing soil quality, vegetative structure, leaf litter depth. The exact mechanism for this is currently being investigated. Overall, the primary issue is that not enough habitat is burned or otherwise disturbed frequently enough to support the plant.