''Bromus secalinus'' is a species of

bromegrass ''Bromus'' is a large genus of grasses, classified in its own tribe Bromeae. They are commonly known as bromes, brome grasses, cheat grasses or chess grasses. Estimates in the scientific literature of the number of species have ranged from 10 ...

known as rye brome. The

specific epithet In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...

''secalinus'' is

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power ...

, meaning "rye-like". The fruits are hard, rounded

glume In botany, a glume is a bract (leaf-like structure) below a spikelet in the inflorescence (flower cluster) of grasses (Poaceae) or the flowers of sedges (Cyperaceae). There are two other types of bracts in the spikelets of grasses: the lemma ...

s that appear superficially similar to the

rye Rye (''Secale cereale'') is a grass grown extensively as a grain, a cover crop and a forage crop. It is a member of the wheat tribe (Triticeae) and is closely related to both wheat (''Triticum'') and barley (genus ''Hordeum''). Rye grain is u ...

grain, which gives the brome its common and scientific name. The grass has a

diploid number Ploidy () is the number of complete sets of chromosomes in a cell, and hence the number of possible alleles for autosomal and pseudoautosomal genes. Sets of chromosomes refer to the number of maternal and paternal chromosome copies, respecti ...

of 28. The grass is native to Eurasia but is well known in many other parts of the world where it has been introduced. It is a

noxious weed A noxious weed, harmful weed or injurious weed is a weed that has been designated by an agricultural or other governing authority as a plant that is injurious to agricultural or horticultural crops, natural habitats or ecosystems, or humans or liv ...

throughout much of North America.

Description

''Bromus secalinus'' is an annual grass that grows high. The upper sheaths are smooth and strongly nerved, and the lower sheaths are glabrous or slightly pubescent. The leaf blades are long and wide, and are covered with short hairs. The

panicles A panicle is a much-branched inflorescence. (softcover ). Some authors distinguish it from a compound spike inflorescence, by requiring that the flowers (and fruit) be pedicellate (having a single stem per flower). The branches of a panicle are ...

are long and wide with spreading or ascending branches. The spreading

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. Morphologically, it is the modified part of the shoot of seed plants where flowers are formed ...

nods when it becomes heavy with grain though prior to maturity the panicle is erect. The spikelets are on elongated pedicels, with each spikelet bearing five to fifteen flowers. The spikelets are glabrous or scabrous and become lax when mature. The ovoid spikelets measure long. The

rachilla Rachilla may refer to the following topics in botany: * Rachilla (floral axis) A spikelet, in botany, describes the typical arrangement of the flowers of grasses, sedges and some other Monocots. Each spikelet has one or more florets. The spikele ...

is obvious in youth and becomes obscured by the expanding

floret This glossary of botanical terms is a list of definitions of terms and concepts relevant to botany and plants in general. Terms of plant morphology are included here as well as at the more specific Glossary of plant morphology and Glossary ...

s with age. The lower

s are three to five-veined and long, and the upper glumes are seven-veined and long. The lemmas become spreading when mature and are strongly inrolled. The lemmas have seven inconspicuous nerves and are long and wide. The awns are straight or curved and are long. The palea is as long or longer than the lemma and its tip slightly projects at maturity. The anthers are long. The

caryopses In botany, a caryopsis (plural caryopses) is a type of simple fruit—one that is monocarpellate (formed from a single carpel) and indehiscent (not opening at maturity) and resembles an achene, except that in a caryopsis the pericarp is fused ...

are thick and strongly inrolled when mature. The grass flowers from June to September. In youth the two

brome grass ''Bromus'' is a large genus of grasses, classified in its own tribe Bromeae. They are commonly known as bromes, brome grasses, cheat grasses or chess grasses. Estimates in the scientific literature of the number of species have ranged from 100 ...

es ''Bromus secalinus'' and '' Bromus arvensis'' are very similar, but are easily distinguishable in maturity. ''Bromus arvensis'' has fully pubescent leaves but ''Bromus secalinus'' lacks

trichome Trichomes (); ) are fine outgrowths or appendages on plants, algae, lichens, and certain protists. They are of diverse structure and function. Examples are hairs, glandular hairs, scales, and papillae. A covering of any kind of hair on a pl ...

s on the undersides of leaves.

Habitat and distribution

''Bromus secalinus'' occurs in fields areas, road verges, and occasionally cornfields, in lightly stony soils. The grass is native to

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a subcontinent of Eurasia and it is located enti ...

but is widespread throughout the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., federal district, five ma ...

and in

Quebec Quebec ( ; )According to the Government of Canada, Canadian government, ''Québec'' (with the acute accent) is the official name in Canadian French and ''Quebec'' (without the accent) is the province's official name in Canadian English is ...

and

British Columbia British Columbia (commonly abbreviated as BC) is the westernmost Provinces and territories of Canada, province of Canada, situated between the Pacific Ocean and the Rocky Mountains. It has a diverse geography, with rugged landscapes that include ...

References

External links

Jepson Manual TreatmentUSDA Plants ProfilePhoto gallery
{{Taxonbar, from=Q161800 secalinus Flora of Asia Flora of Europe Plants described in 1753 Taxa named by Carl Linnaeus