Acalypha rhomboidea
Encyclopedia
Acalypha rhomboidea is a plant
in the spurge family, Euphorbiaceae
.
herbaceous
plant. It grows from a taproot, reaching 1/2–2 feet (15–61 cm) tall, and is usually without branches. The central stem can be either covered with fine white hairs or hairless. The lanceolate to lanceolate-rhombic
acute leaves are alternate with slightly hairy petioles
about 1.5 inches (4 cm) long, bluntly serrated margins, and pinnate venation. Leaves are deep green and somewhat shiny above, light green and mostly hairless below and can be up to 2.75 inches (7 cm) long and 1.5 inches (4 cm) wide. There is a tendency for the leaves to cluster near the top of the stem or stems. A conspicuous, slightly ciliate bract
with 5-9 lobes is located where the leaf petiole meets the stem. This bract wraps around the inflorescence
, which consists of a green cyathium
. The cyathium contains minute staminate and pistillate flowers lacking petals. Male flowers terminate the peduncle
with capitate clusters. The flowers consists of 4 tiny golden green upwardly bent sepals, acute to blunt in shape, and many stamens. Female flowers consist of minute green sepals, a hairy tri-locular
ovary, and three fringed styles. One seed per locule is produced. The mature pods are tan colored, 1/15" (1.6-1.8mm) long, and deeply lobed. There is no floral scent associated with the flowers.
This plant is somewhat unusual in that it has clear sap as opposed to the typically milky sap of other members of Euphorbiaceae.
Acalypha rhomboidea is quite similar to Acalypha virginica. The two may be distinguished by the number of lobes on the bracts; the latter has 9-15 lobes whereas the former has only 5-9. Acalypha rhomboidea also resembles young Redroot pigweed (Amaranthus retroflexus
L.), but may be distinguished from the latter by the flower clusters, bracts, and occasionally bronze-green leaves of the former.
", was applied to this genus by Linnaeus because of the nettle-like appearance of the leaves. The species name "rhomboidea" means diamond-shaped.
Canada
and the Northeastern
, Southeastern
, and Central
United States
.
This plant often grows in fertile loam
, but it will tolerate gravelly or clay soil as well. It prefers disturbed areas
. Three-seeded mercury can be found growing in moist to mesic
black soil prairie
, openings or lightly shaded areas of upland and floodplain forest, thickets, seeps
, riverbanks
and lake shores, limestone glades
and bluffs
, fields, fence rows, roadside and railroad right-of-ways, vacant lots, and waste areas.
The seeds are an attractive food source for birds such as the Mourning Dove
and Greater Prairie Chicken
. Deer are known to browse Acalypha
spp.
In crop fields where group 2 herbicides have been repeatedly used this plant can become a serious and damaging weed
.
Plant
Plants are living organisms belonging to the kingdom Plantae. Precise definitions of the kingdom vary, but as the term is used here, plants include familiar organisms such as trees, flowers, herbs, bushes, grasses, vines, ferns, mosses, and green algae. The group is also called green plants or...
in the spurge family, Euphorbiaceae
Euphorbiaceae
Euphorbiaceae, the Spurge family are a large family of flowering plants with 300 genera and around 7,500 species. Most are herbs, but some, especially in the tropics, are also shrubs or trees. Some are succulent and resemble cacti....
.
Description
Common three-seeded mercury is an annualAnnual plant
An annual plant is a plant that usually germinates, flowers, and dies in a year or season. True annuals will only live longer than a year if they are prevented from setting seed...
herbaceous
Herbaceous
A herbaceous plant is a plant that has leaves and stems that die down at the end of the growing season to the soil level. They have no persistent woody stem above ground...
plant. It grows from a taproot, reaching 1/2–2 feet (15–61 cm) tall, and is usually without branches. The central stem can be either covered with fine white hairs or hairless. The lanceolate to lanceolate-rhombic
Rhombus
In Euclidean geometry, a rhombus or rhomb is a convex quadrilateral whose four sides all have the same length. The rhombus is often called a diamond, after the diamonds suit in playing cards, or a lozenge, though the latter sometimes refers specifically to a rhombus with a 45° angle.Every...
acute leaves are alternate with slightly hairy petioles
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...
about 1.5 inches (4 cm) long, bluntly serrated margins, and pinnate venation. Leaves are deep green and somewhat shiny above, light green and mostly hairless below and can be up to 2.75 inches (7 cm) long and 1.5 inches (4 cm) wide. There is a tendency for the leaves to cluster near the top of the stem or stems. A conspicuous, slightly ciliate bract
Bract
In botany, a bract is a modified or specialized leaf, especially one associated with a reproductive structure such as a flower, inflorescence axis, or cone scale. Bracts are often different from foliage leaves. They may be smaller, larger, or of a different color, shape, or texture...
with 5-9 lobes is located where the leaf petiole meets the stem. This bract wraps around 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...
, which consists of a green cyathium
Cyathium
A cyathium is one of the specialised pseudanthia forming the inflorescence of plants in the genus Euphorbia . A cyathium consists of:...
. The cyathium contains minute staminate and pistillate flowers lacking petals. Male flowers terminate the peduncle
Peduncle (botany)
In botany, a peduncle is a stem supporting an inflorescence, or after fecundation, an infructescence.The peduncle is a stem, usually green and without leaves, though sometimes colored or supporting small leaves...
with capitate clusters. The flowers consists of 4 tiny golden green upwardly bent sepals, acute to blunt in shape, and many stamens. Female flowers consist of minute green sepals, a hairy tri-locular
Locule
A locule is a small cavity or compartment within an organ or part of an organism ....
ovary, and three fringed styles. One seed per locule is produced. The mature pods are tan colored, 1/15" (1.6-1.8mm) long, and deeply lobed. There is no floral scent associated with the flowers.
This plant is somewhat unusual in that it has clear sap as opposed to the typically milky sap of other members of Euphorbiaceae.
Acalypha rhomboidea is quite similar to Acalypha virginica. The two may be distinguished by the number of lobes on the bracts; the latter has 9-15 lobes whereas the former has only 5-9. Acalypha rhomboidea also resembles young Redroot pigweed (Amaranthus retroflexus
Amaranthus retroflexus
Amaranthus retroflexus is a species of flowering plant in the Amaranthaceae family with several common names, including Red-root Amaranth, Redroot Pigweed, Red Rooted Pigweed, Common Amaranth, and common tumble weed....
L.), but may be distinguished from the latter by the flower clusters, bracts, and occasionally bronze-green leaves of the former.
Taxonomy
The genus name Acalypha, which comes from the ancient Greek "acklephes" for "nettleNettle
Nettles constitute between 24 and 39 species of flowering plants of the genus Urtica in the family Urticaceae, with a cosmopolitan though mainly temperate distribution. They are mostly herbaceous perennial plants, but some are annual and a few are shrubby...
", was applied to this genus by Linnaeus because of the nettle-like appearance of the leaves. The species name "rhomboidea" means diamond-shaped.
Distribution and habitat
Acalypha rhomboidea is native to EasternEastern Canada
Eastern Canada is generally considered to be the region of Canada east of Manitoba, consisting of the following provinces:* New Brunswick* Newfoundland and Labrador* Nova Scotia* Ontario* Prince Edward Island* Quebec...
Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
and the Northeastern
Northeastern United States
The Northeastern United States is a region of the United States as defined by the United States Census Bureau.-Composition:The region comprises nine states: the New England states of Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island and Vermont; and the Mid-Atlantic states of New...
, Southeastern
Southeastern United States
The Southeastern United States, colloquially referred to as the Southeast, is the eastern portion of the Southern United States. It is one of the most populous regions in the United States of America....
, and Central
Central United States
The Central United States is sometimes conceived as between the Eastern United States and Western United States as part of a three-region model, roughly coincident with the Midwestern United States plus the western and central portions of the Southern United States; the term is also sometimes used...
United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
.
This plant often grows in fertile loam
Loam
Loam is soil composed of sand, silt, and clay in relatively even concentration . Loam soils generally contain more nutrients and humus than sandy soils, have better infiltration and drainage than silty soils, and are easier to till than clay soils...
, but it will tolerate gravelly or clay soil as well. It prefers disturbed areas
Ruderal species
A ruderal species is a plant species that is first to colonize disturbed lands. The disturbance may be natural , or due to human influence – constructional , or agricultural .Ruderal species typically dominate the disturbed area...
. Three-seeded mercury can be found growing in moist to mesic
Mesic habitat
In ecology, a mesic habitat is a type of habitat with a moderate or well-balanced supply of moisture, e.g., a mesic forest, a temperate hardwood forest, or dry-mesic prairie. Compared to a dry habitat, a mesic habitat is moister....
black soil prairie
Prairie
Prairies are considered part of the temperate grasslands, savannas, and shrublands biome by ecologists, based on similar temperate climates, moderate rainfall, and grasses, herbs, and shrubs, rather than trees, as the dominant vegetation type...
, openings or lightly shaded areas of upland and floodplain forest, thickets, seeps
Seep (hydrology)
A Seep is a moist or wet place where water, usually groundwater, reaches the earth's surface from an underground aquifer.-Description:Seeps are usually not of sufficient volume to be flowing beyond their above-ground location. They are part of the limnology-geomorphology system...
, riverbanks
Riparian zone
A riparian zone or riparian area is the interface between land and a river or stream. Riparian is also the proper nomenclature for one of the fifteen terrestrial biomes of the earth. Plant habitats and communities along the river margins and banks are called riparian vegetation, characterized by...
and lake shores, limestone glades
Glade (geography)
A glade or clearing is an open area within a woodland. Glades are often grassy meadows under the canopy of deciduous trees such as red alder or quaking aspen in western North America. They also represent openings in forests where local conditions such as avalanches, poor soils, or fire damage have...
and bluffs
Cliff
In geography and geology, a cliff is a significant vertical, or near vertical, rock exposure. Cliffs are formed as erosion landforms due to the processes of erosion and weathering that produce them. Cliffs are common on coasts, in mountainous areas, escarpments and along rivers. Cliffs are usually...
, fields, fence rows, roadside and railroad right-of-ways, vacant lots, and waste areas.
Ecology
The blooming period for this plant is roughly mid-summer until fall frost, and last for one or more months.The seeds are an attractive food source for birds such as the Mourning Dove
Mourning Dove
The Mourning Dove is a member of the dove family . The bird is also called the Turtle Dove or the American Mourning Dove or Rain Dove, and formerly was known as the Carolina Pigeon or Carolina Turtledove. It is one of the most abundant and widespread of all North American birds...
and Greater Prairie Chicken
Greater Prairie Chicken
The Greater Prairie Chicken or Pinnated Grouse, Tympanuchus cupido, is a large bird in the grouse family. This North American species was once abundant, but has become extremely rare or extinct over much of its range due to habitat loss. There are current efforts to help this species gain the...
. Deer are known to browse Acalypha
Acalypha
Acalypha is a plant genus of the family Euphorbiaceae. It is the sole genus of the subtribe Acalyphinae. With 450 to 500 species of herbs and shrubs, the genus is only behind Euphorbia, Croton and Phyllanthus in term of Malpighiales diversity...
spp.
In crop fields where group 2 herbicides have been repeatedly used this plant can become a serious and damaging weed
Weed
A weed in a general sense is a plant that is considered by the user of the term to be a nuisance, and normally applied to unwanted plants in human-controlled settings, especially farm fields and gardens, but also lawns, parks, woods, and other areas. More specifically, the term is often used to...
.