Perennial cereal grasses, or Poaceae, herbs are perennial grasses of the Poaceae family.
Classification
According to the nature of shoot formation, perennial grasses are classified into:
- rhizomatous, in which the rhizome, that is, the underground part of the stem, is located underground at a depth of 5-20 cm, new shoots are formed from buds located on the rhizome and at the base of old shoots, for example, awnless rump, creeping couch grass, meadow bluegrass;
- loose shrubs, in which the tillering node is at a depth of 1-5 cm, new shoots depart at an acute angle from the mother, forming a loose bush, for example, meadow timothy , meadow fescue , hedgehog team;
- dense bush, in which the tillering node is above the soil surface or at a depth of 1-2 cm, new shoots develop straight up, closely adjacent to the mother, forming a dense bush;
- rhizome-loose bush, which have features characteristic of rhizomatous and loose bush grasses, that is, part of the shoots has rhizomes, the other part forms a loose bush, for example, meadow foxtail, red fescue.
According to the height of the stems and the nature of the foliage, bluegrass herbs are divided into:
- riding, that is, tall with good foliage;
- grassroots, that is, slightly leafy with shortened shoots in the surface layer;
- semi-mounted, occupying an intermediate position between the first two.
Biological features
For all types of perennial cereal grasses, with the exception of awnless brome , the following biological features are characteristic.
Each developed stem of the plant lives for one year, therefore, when mowing bluegrass grasses for hay, the second cut is formed due to vegetative shoots.
Loose-bush grasses grow continuously. The most intensive tillering occurs in early spring and autumn. Young shoots formed in the soil during vegetative renewal consume moisture and nutrients through the root system of the mother shoot. So, in young shoots, for example, timothy , the synthesizing effect of the sucrose enzyme is observed only on the 15th day of life, which means that the shoot formed from the spare bud feeds on the mother plant for 2 weeks and only then does the productive work of the leaves of the new shoot begin.
Each new shoot has its own root system. For all loose-bush bluegrass grasses, there is a so-called critical mowing zone, that is, a height, mowing below which leads to the death of a vegetative shoot. The critical mowing zone coincides with the location of the growing point of the vegetative shoot. If the mower knife cuts off the growth point completely or partially, then the shoot stops further growth and dies. For most perennial grasses, the critical zone is located at a height of 5-6 cm from the soil surface. This biological feature is taken into account when mowing grasses to ensure a good harvest of the second mowing.
The maximum increase in the above-ground part for all bluegrass herbs falls on the period from the beginning of the emergence into the tube until the completion of the heading phase or panicle sprouting. This period corresponds to the maximum consumption of nutrients and water from the soil.
Grasses are particularly responsive to nitrogen fertilization.
Under optimal conditions, the yield can be maintained for 5-10 years of cultivation in one place. In upland conditions, life expectancy, for example, for timothy grass is 4-5 years, in the lower third of the slope or in lowland meadows – 8-10 years. For this reason, crop rotations are introduced in seed farms specializing in the cultivation of grass seeds, in which perennial grasses account for up to 80% of the crop rotation area. So, for the Non-Chernozem zone, crop rotation schemes are recommended:
- 1 – Poaceae grasses (uncovered sowing); 2-4 – bluegrass grasses for seeds; 5-6 – tilled fodder crops and potatoes ; 7 – bluegrass with clover overseeding; 9 – clover for seeds;
- 1 – Poaceae grasses (uncovered sowing); 2-4 – herbs for seeds; 5-6 – row crops (potatoes, fodder root crops, corn).
Perennial bluegrass grasses form a powerful root system. The ratio of the mass of underground organs to the mass of above-ground organs in the flowering phase of meadow fescue is 0.81, the cocksfoot is 0.82, and the awnless rump is 1.08 (All-Russian Research Institute of Fodder). This biological feature contributes to the accumulation of organic matter in the soil during the cultivation of perennial bluegrass grasses.
Major crops
Perennial grasses include:
- Bromus inermis;
- wheatgrass (Agropyron);
- meadow fescue (Festuca pratensis);
- meadow timothy (Phleum pratense);
- hedgehog team (Dactylis glomerata);
- ryegrass high (Arrhenatherum elatius);
- ryegrass multicut (Festuca perennis);
- rootless wheatgrass (?);
- Siberian wheatgrass (Elymus sibiricus);
- meadow foxtail (Alopecurus pratensis).
Meaning
Perennial grasses are grown in mixed crops with legumes. Joint sowing of bluegrass and legume grasses makes it possible to equalize the harvest over the years, increase the duration of use of grass stands, and balance the nutritional qualities of grass mixtures.
100 kg of dry matter of perennial grasses harvested in the heading phase (panicle heading) contain 70 feed units and 8 kg of protein, in the flowering phase – 45 feed units (V.R. Williams All-Russian Research Institute of Feed).
Protection of seed crops from diseases of pests and weeds
In crops of perennial cereal grasses intended for seeds, to combat helminthosporiasis, crops are sprayed with Tilt, Atlant, Titan, Title 250, Title 390 preparations.
To combat the ear fly, spraying is carried out in the phase of the latent formation of the sultan with Diazolin.
To combat annual dicotyledonous weeds, crops are sprayed with preparations 2,4-D, Dezormon, Aminopelik, Octapon Extra, Agritoks.
Sources
Crop production / P.P. Vavilov, V.V. Gritsenko, V.S. Kuznetsov and others; Ed. P.P. Vavilov. – 5th ed., revised. and additional – M.: Agropromizdat, 1986. – 512 p.: ill. – (Textbook and textbooks for higher educational institutions).
V.V. Kolomeichenko. Crop production / Textbook. — M.: Agrobusinesscenter, 2007. — 600 p. ISBN 978-5-902792-11-6.
Fundamentals of agricultural production technology. Agriculture and crop production. Ed. V.S. Niklyaev. – M .: “Epic”, 2000. – 555 p.