Bromus hordeaceus

Soft brome ( Bromus hordeaceus )

The soft brome or downy brome ( Bromus hordeaceus ) is a species of grass from the family of grasses ( Poaceae ).

Features

The Soft Trepse grows as a one-year, mostly winterannuelles grass - so they usually germinates in the fall and bloom and bear fruit the following year. The plant grows in tufts or individual blades and is on the whole gray-green. The stalks are 10 to 90 cm high, below the inflorescence and at the nodes they are hairy. The leaf sheaths are serrated, the lower are usually densely hairy soft, the hairs are 1 to 1.5 mm long. The upper leaf sheaths are often hairy only at the edges or completely bald. The ligule is a densely hairy, membranous hem of 2 to 2.5 mm in length. The leaf blades are 5-25 cm long and 2-5 (rarely 7) mm wide. They are flat - spread and hairy soft and short on both sides.

The inflorescence is a panicle 2-15 cm long, which is upright and contracted. The lower side branches are usually upright, are pubescent and up to 5 cm long. The stems of the spikelets are rough and usually shorter than the spikelets. These consist of 6 to 12 petals and are without awns 14-22 mm long. The glumes are membranous, covered with short thick and rough on the nerves. The lower glume is three to five annoying (rarely seven annoying ), 5-8 mm long, elongated, pointed shape. The upper glume is five to seven annoying, 6-10 mm long, ovate and pointed. The lemma is seven to nine annoying, 8-11 mm long, oblong to ovate, sinuate above and thin-skinned with margins narrow, white - transparent. In the upper two -thirds of it is covered with dense hair. She wears a 5 to 10 mm long, straight awn. The palea are two annoying and 1.5 to 2 mm shorter than the lemmas. On the quills they have about 0.5 mm long, stiff protruding eyelashes. The dust bags are from 0.3 to 2 mm long. Flowering season is from May to July in sommerannuellen plants into October.

The caryopses are 6-7 mm long and slightly shorter than the palea. At its upper end, she wears a membranous, hairy appendages. In cross-section, it is thin and flat U-shape.

The chromosome number is 2n = 28

Ecology

Because of the striking dependence of plant height on the nutrient content of the soil, the Soft brome is a vivid example of modifications; so Kümmerformen can in extreme cases, have only one spikelet. The spread of the points brome occurs mainly by humans. Therefore, the species is now abducted and in many places around the world, eg in Australia a nuisance.

Dissemination and locations

The Soft brome is native to Europe and West Asia and North Africa, North and South America and Australia it was introduced.

In Central Europe the Soft brome is common and frequent. It rises from the plains up to middle mountain areas. About 500 m it is rare, but in the Alps it occurs up to 1000 m, adventiv to 1680 m.

It grows in weed societies, especially in the vicinity of towns, in dry meadows, cornfields, on sand fields, grass courts, on dunes, embankments, roads and fences, yards and dumps. It prefers moderately dry, nutrient-rich sand and clay soils. The Soft brome is a nutrient indicator. On dry sites it tends to greatly reduced growth, the plants often form then only a single spikelet.

The Soft brome is a Ordnungskennart the fertilized fresh meadows and pastures ( Arrhenatheretalia ), particularly in oat grass meadows ( Arrhenatherion ), as well as in mice barley Society ( Hordeetum Murini ) and other Raukengesellschaften ( Sisymbrion ).

System

The soft brome was first published in 1753 by Carl Linnaeus in Species Plantarum. The scope of the type Bromus hordeaceus will vary broadly by different authors. Some clans are either as subspecies of Bromus hordeaceus or as a separate species within the group of species Bromus hordeaceus agg. construed.

Are largely performed as subspecies:

• Actual Soft brome ( Bromus hordeaceus subsp. Hordeaceus ), the nominate form. It is a tetraploid family, widespread in Central Europe and very common.
• Incorrect Dune brome ( Bromus hordeaceus subsp pseudothominei. ): Also a tetraploid clan, with main distribution in north-west Europe.
• Upright beach - brome ( Bromus hordeaceus subsp divaricatus. ): Native to the Mediterranean region, isolated in Central Europe only.

• The also sometimes subsp as a subspecies Bromus hordeaceus. thominei guided dune brome is classified today thominei rather as a separate species Bromus.

A long in use synonym for Bromus Bromus mollis L. hordeaceus is that in 1762 has lower priority due to its later first publication.

Importance

The soft brome can occur in premolars fat meadows and cultivated fields as a weed. Since they aussamt before the first mowing, it is difficult to combat. Because the yellowing leaves early, the grass is ertragsarm and agriculturally inferior. As control measures good fertilization and maintenance of a closed sward apply. In the past, soft brome was sometimes recommended as a " German rye-grass " for fodder crops, in North Germany there was even seed growing.

Documents

In addition to the sources listed in the detailed records of the products based on the following documents:

• Hans Joachim Conert: Pareys grasses book. Identify and determine the grasses Germany. Blackwell, Berlin / Vienna 2000, ISBN 3-8263-3327-6, p 138
• Ruprecht Duell, Herfried Kutzelnigg: Pocket Dictionary of Plants in Germany and neighboring countries. The most common central European species in the portrait. 7, revised and expanded edition. Quelle & Meyer, Wiebelsheim 2011, ISBN 978-3-494-01424-1.