Acalypha ostryaefolia
Encyclopedia
Acalypha ostryifolia is a plant in the Euphorbiaceae
family and is commonly known as hophornbeam copperleaf or pineland three-seed mercury. It is a native of North and Central America and is generally considered a weed
.
are upright, branching, purplish-green with vertical striations, short recurved hairs and stalked glands. The leaves are alternate, petiolate
, simple and ovate with dentate margins, a cordate base and slight pubescence. Male and female flowers are in separate spikes, the males axillary and the females terminal. The male flowers have four ovate greenish sepal
s often tinged red and no petal
s. The female flowers are also petal-less but have three styles which subdivide into white hairs which give the inflorescence
a furry appearance. The fruit are green capsule
s with three chambers, sparsely haired, with fleshy green glandular outgrowths. The seed
s are brown with low bumpy ridges. Flowering time is from June to November.
rate and the seedlings are resistant to cold and grow as fast as soybean
plants in the Midwest. It is resistant to most of the herbicide
s used in soybean crops with the exception of lactofen
, acifluorfen
and fomesafen, which controlled over 80%. Lactofen was the most successful of these with a kill rate of 95%.
The spotted lady beetle
commonly lays eggs on this plant when it grows near sweet corn crops in Kentucky. Research has shown that the insect favoured the weed over the corn, even though it was not infested by aphids on which the larvae could feed. The larvae were found to fall from the weeds and crawl across the soil before climbing sweet corn plants. The presence of the weed in close proximity to the crop was beneficial and resulted in more beetle larvae on the crop and fewer aphids than was the case when the weed was absent.
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....
family and is commonly known as hophornbeam copperleaf or pineland three-seed mercury. It is a native of North and Central America and is generally considered a 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...
.
Distribution
A. ostryifolia is found in the southern and eastern United States, Cuba, Dominican Republic, Haiti, Jamaica, Puerto Rico, Mexico, Guatemala, Belize, Costa Rica, El Salvador, Honduras and Nicaragua.Description
The hophornbeam copperleaf is an annual herb reaching a height of one to three feet. The stemsPlant stem
A stem is one of two main structural axes of a vascular plant. The stem is normally divided into nodes and internodes, the nodes hold buds which grow into one or more leaves, inflorescence , conifer cones, roots, other stems etc. The internodes distance one node from another...
are upright, branching, purplish-green with vertical striations, short recurved hairs and stalked glands. The leaves are alternate, petiolate
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...
, simple and ovate with dentate margins, a cordate base and slight pubescence. Male and female flowers are in separate spikes, the males axillary and the females terminal. The male flowers have four ovate greenish sepal
Sepal
A sepal is a part of the flower of angiosperms . Collectively the sepals form the calyx, which is the outermost whorl of parts that form a flower. Usually green, sepals have the typical function of protecting the petals when the flower is in bud...
s often tinged red and no petal
Petal
Petals are modified leaves that surround the reproductive parts of flowers. They often are brightly colored or unusually shaped to attract pollinators. Together, all of the petals of a flower are called a corolla. Petals are usually accompanied by another set of special leaves called sepals lying...
s. The female flowers are also petal-less but have three styles which subdivide into white hairs which give 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...
a furry appearance. The fruit are green capsule
Capsule (fruit)
In botany a capsule is a type of simple, dry fruit produced by many species of flowering plants. A capsule is a structure composed of two or more carpels that in most cases is dehiscent, i.e. at maturity, it splits apart to release the seeds within. A few capsules are indehiscent, for example...
s with three chambers, sparsely haired, with fleshy green glandular outgrowths. The seed
Seed
A seed is a small embryonic plant enclosed in a covering called the seed coat, usually with some stored food. It is the product of the ripened ovule of gymnosperm and angiosperm plants which occurs after fertilization and some growth within the mother plant...
s are brown with low bumpy ridges. Flowering time is from June to November.
Ecology
The hophornbeam copperleaf is a summer weed growing in cultivated fields and waste places. It has a high germinationGermination
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...
rate and the seedlings are resistant to cold and grow as fast as soybean
Soybean
The soybean or soya bean is a species of legume native to East Asia, widely grown for its edible bean which has numerous uses...
plants in the Midwest. It is resistant to most of the herbicide
Herbicide
Herbicides, also commonly known as weedkillers, are pesticides used to kill unwanted plants. Selective herbicides kill specific targets while leaving the desired crop relatively unharmed. Some of these act by interfering with the growth of the weed and are often synthetic "imitations" of plant...
s used in soybean crops with the exception of lactofen
Lactofen
Lactofen is a complex ester of acifluorfen and is a nitrophenyl ether selective herbicide. It is used in postemergence applications to certain crops which are resistant to its action. The name "Lactofen" is approved by the American National Standards Institute and the Weed Science Society of...
, acifluorfen
Acifluorfen
Acifluorfen is an herbicide. It is effective against broadleaf weeds and grasses and is used agriculturally on fields growing soybeans, peanuts, peas, and rice.-See also:* Lactofen, an ester derivative also used as an herbicide....
and fomesafen, which controlled over 80%. Lactofen was the most successful of these with a kill rate of 95%.
The spotted lady beetle
Spotted lady beetle
Coleomegilla maculata, commonly known as the spotted lady beetle, pink spotted lady beetle or twelve-spotted lady beetle, is a large coccinellid beetle native to North America...
commonly lays eggs on this plant when it grows near sweet corn crops in Kentucky. Research has shown that the insect favoured the weed over the corn, even though it was not infested by aphids on which the larvae could feed. The larvae were found to fall from the weeds and crawl across the soil before climbing sweet corn plants. The presence of the weed in close proximity to the crop was beneficial and resulted in more beetle larvae on the crop and fewer aphids than was the case when the weed was absent.