Agrostis

Agrostis is a genus of plants in the Poaceae family that consists of more than 100 species of herbs, most of them perennial. Some of them are used for grass meadows. The flowers appear in loose panicles; each of the small spikelets contains a single flower. As a species of forage interest, it has little nutritional value and is not very productive. Among the most common species are Agrostis castellana and Agrostis stolonifera, the latter widely used on golf courses as it is highly invasive and creates a perfect mat for practicing this sport..

Identification

The genus Agrostis is characterized by having more or less open panicles, with small pedicelate spikelets on whorled peduncles on the axis of the inflorescence. Glumes more or less equal, acute, pointed or awned and keeled, longer than the glumes, and enclosing a single fertile flower, often with another rudimentary. Pointy bluish-green leaves, short ligule, and no auricles. It has well-developed rhizomes, the stems are creeping and root in the nodes. They are small size and consistency plants, most of them are annuals, with flat leaves.

The grain, in a caryopsis, is wrapped in glumes and can be oblong or ellipsoid in shape and dark-amber or reddish in color.

The seeds are very small, one gram contains around 15,000 seeds, so their collection is complicated and the price is high.

Distribution and habitat

They are abundant species in Spanish grasslands. They are also found in Northern Europe, Argentina, Brazil and North America. They are adapted to the winter period and resist cold and excess humidity well, which is why they tend to develop in flooded depressions, banks and banks of ditches.

Among the most interesting species in the Iberian Peninsula are:

• Agrostis stolonifera lives in almost all Spain, at medium altitudes, although it climbs to the mountain floor.
• Agrostis castellana lives at lower altitudes, across the west half of the Peninsula, mainly in Extremadura, along with species of the genus Lollium.
• Agrostis nevadensis is located in Sierra Nevada.
• Agrostis alpinea in the Cantabrian mountain range and Pyrenees.
• Agrostis rupestris, it is also found in alpine pastures and subalpines of the north and center of the Peninsula.

Crop and environmental needs

Seeds Agrostis stolonifera

They are rustic plants capable of growing in poor and acidic environments. In addition, they resist well to excess winter humidity and are quite appetizing for cattle. They provide an appreciable amount of plant material that would not be possible with more demanding species.

Each species has its specific requirements, but in general, they do not develop at altitudes higher than 1000 meters of altitude. The land must be well prepared, with plenty of fine soil, due to the small size of its seeds.

The most suitable time for planting is at the end of summer or beginning of autumn. The optimal germination temperature ranges between 20-30 °C. It takes between 10 and 15 days to germinate from sowing if the conditions are right. It is a kind of long photoperiod, requiring more than 16 hours of light per day. It has water needs, in terms of approximate annual ETc, of 1200 mm.

For seed production, its fruiting period can be quite long, taking place between April and September, although the largest quantity of seeds can be collected during the month of July.

Crop Adversities

It is relatively sensitive to attack by pathogenic fungi, mainly Pythium and Fusarium roseum. Preventive fungicide treatments must be applied systematically at times of greatest risk.

They are species that are not very aggressive when implanted and have a low rate of occurrence, that is, they are not easy to implant.

Its production is surpassed in quantity and quality by other species, so its objective is not productive pastures but ornamental or sports lawns, and to a lesser degree, revegetation.

Uses and exploitation

Spontaneous species in the grasslands of the Iberian Peninsula are abundant, although they have little nutritional value.

The forage of A. stolonifera is unappetizing for sheep and a little more for cattle, its average composition being: water, 15 %; dry matter, 80%; crude protein, 7%; fats, 2%; fibers, 25%; ash, 6.5%. This species is typical of golf course greens, as it has a uniform plant surface and low susceptibility to degradation.

The genus Agrostis includes species that, even though they are not very productive, with proper fertilization, can produce 2 to 3 cuts per year of a forage that supports good tedding.

Taxonomy

The genus was described by Carlos Linnaeus and published in Species Plantarum 1: 61. 1753. The type species is: Agrostis canina L.

Etymology

Agrostis: generic name derived from the Greek agrostis = (a fodder plant, a kind of grass), cf. agros = (field).

Intergenic hybrid

• Agrostis + Polypogon (×'Agropogon' P.Fourn.)