Elymus repens
(quackgrass)

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Identity

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Preferred Scientific Name

• Elymus repens (L.) Gould 1947

Preferred Common Name

• quackgrass

Other Scientific Names

• Agropyron repens (L.) Beauv. (1812)
• Elytrigia repens (L.) Nevski 1933
• Triticum repens L. (1753)

International Common Names

• English: couch grass; quack grass
• Spanish: grama de Europa
• French: chiendent rampant
• Portuguese: grama-francesa

Local Common Names

• Germany: (gemeine) Quecke
• Italy: agropiro comune; caprinella; gramigna; granaccio
• Japan: himekamojigusa; shibamugi
• Netherlands: kweek
• Sweden: kvickrot

EPPO code

• AGRRE (Elytrigia repens)

Taxonomic Tree

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• Domain: Eukaryota
•     Kingdom: Plantae
•         Phylum: Spermatophyta
•             Subphylum: Angiospermae
•                 Class: Monocotyledonae
•                     Order: Cyperales
•                         Family: Poaceae
•                             Genus: Elymus
•                                 Species: Elymus repens

Notes on Taxonomy and Nomenclature

Top of page The name most commonly used in agricultural literature up to recent years has been Agropyron repens. Linnaeus called the species Triticum repens because its inflorescence arrangement is similar to that of wheat and related plants. The common names couch or couch grass are frequently used, but are also often used for other rhizomatous grass species. Holm et al. (1977) therefore prefer the name quackgrass, and this, or quack grass, is the name most frequently used in North America.

Variability

E. repens is a very variable perennial species. In Flora Europaea (1964-80), five subspecies are recognized. The most widespread, ssp. repens, is strongly rhizomatous and is the subspecies important as a weed on cultivated land. It is also a frequent plant on other disturbed ground and in waste places within its distribution areas. Chromosome number is 2n=28 or 42 (Bor, 1960).

The subdivision of E. repens may be questioned and needs more thorough investigation, for example by comparison of plants from different geographical areas. Attempts to subdivide ssp. repens on the basis of morphological differences are doubtful (cf. Håkansson, 1967). As cross-pollination is predominant, sexual reproduction results in genotypically different clones which sometimes show morphological differences, e.g. in the inflorescence, within narrow areas. These differences, however, may have only a slight ecological or agronomic significance.

Description

Top of page After Flora Europaea (1964-80); Håkansson (1967); Holm et al. (1977).

E. repens ssp. repens is a rhizomatous perennial grass developing erect culms, which are more or less curved at the base. Their length is between 30 and 120 cm.

Leaf blades are soft and relatively flat, 3-10 mm wide, dull and mostly dark green, sometimes glaucous. On the lower leaves, sheaths are often strongly hairy, on upper leaves smooth or slightly soft-hairy. Growth-chamber experiments in Sweden show that the sheaths become hairier at low than at high temperatures (S. Håkansson, Swedish University of Agricultural Sciences, Uppsala, unpublished data, 1995). Auricles occur at the junction of the sheath and blade.

The inflorescence is a dense to rather lax spike, like a wheat spike but more slender, mostly 5-10 cm long. Spikelets are compressed, 5-15 mm long, usually with four to six flowers. Glumes are 5-15 mm long, lanceolate and mostly awn-pointed, lemma 6-11 mm with an awn from less than 1 mm up to about 10 mm. Seeds are enclosed in the glumes, forming a spool-shaped unit, broadest below the middle. The caryopsis is usually 4-5 mm long.

Rhizomes are pale yellow or straw-coloured with internodes from 2-8 cm in length and about 3 (1.5-4) mm in diameter. Their nodes, with more or less differentiated buds, are originally covered with scaly sheaths, which decay rather rapidly. Their apices are enclosed by sheaths which form a scaly cover ending in a sharp tip. The rhizomes are mostly creeping between the soil surface and a depth of 5-10 cm, or up to 20 cm in loose soil. Rhizomes may reach lengths of more than 1 m under favourable growth conditions. Fibrous roots develop from their nodes.

Distribution

Top of page E. repens is a serious agricultural and horticultural weed mainly in temperate climates in the northern hemisphere, and to some extent in cool climates at higher altitudes within warmer regions. It is particularly important in the northernmost, cooler, agricultural areas, where it seems to be more competitive in perennial crops than further south (Håkansson, 1969b, 1982; Holm et al., 1977). It is reported as an important weed of coffee in higher, cooler areas of New Guinea and is found in scattered sites in the cooler mountain valleys of Central and South America (Holm et al., 1977). The occurrence of this species, a C3 plant, in temperate climates and its absence in the warm tropics may be due to difficulties in producing rhizomes at higher temperatures, which has been demonstrated experimentally (Håkansson, 1969b).

Distribution Table

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The distribution in this summary table is based on all the information available. When several references are cited, they may give conflicting information on the status. Further details may be available for individual references in the Distribution Table Details section which can be selected by going to Generate Report.

Last updated: 23 Apr 2020

Habitat

Top of page The species grows on many types of soil, both mineral and organic. It seems to be most competitive on fertile soils, rich in nitrogen and with a good water supply, and is less successful on very acid or very dry, shallow soils (Ellenberg, 1974; Holm et al., 1977; Wedin and Tilman, 1996).

Host Plants and Other Plants Affected

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Biology and Ecology

Top of page E. repens ssp. repens is a rhizomatous perennial grass with both vegetative and sexual reproduction. It propagates easily by the rhizomes, even short fragments of which are regenerative if they include a node. The plant can therefore be rapidly spread and multiplied by soil cultivation, and where competition from other plants is not too strong, undisturbed plants can develop rapidly extending clones. In a short-term perspective, vegetative propagation dominates quantitatively and contributes to the special character of the species as a weed. However, following very thorough control of this weed in the field, surviving seeds will be important (together with surviving rhizome fragments) for initiating a new weed population. Furthermore, the seeds enable the formation of new genotypes, which is promoted by the prevalent cross-pollination. Because of a high degree of self-sterility (see Beddows, 1931), seed production is variable but on the whole high. Although the seeds have no, or no lengthy, innate dormancy (cf. Williams, 1968), a soil seed bank of considerable importance usually builds up (Korsmo, 1925; Palmer and Sagar, 1963; Håkansson, 1967, 1969a, 1970; Williams, 1970; Williams and Attwood, 1971).

Seedlings normally begin to develop rhizomes when they have four to six foliar leaves. Until then, they are as sensitive to mechanical disturbance as seedlings of annual plants. After rhizomes have developed, the plants are comparable to those developed from rhizome buds (Håkansson, 1970; Williams, 1970).

According to experiments by Håkansson (1967, 1969b, 1974, 1995) studying E. repens, its undisturbed growth and susceptibility to mechanical and chemical disturbance can be described as follows. In undisturbed clones, new plants or plant units (i.e. aerial shoots and attached adventitious roots) mainly develop from the apices of rhizome branches, whereas apical dominance prevents axillary buds from being activated. On the other hand, axillary rhizome buds are activated to a greater extent by soil cultivation or other disturbances breaking or wounding the rhizome system. Such buds then greatly contribute to the development of new plants. In studying 'late-spring dormancy' as described by Johnson and Buchholz (1962), Håkansson (1967) interpreted this dormancy to be merely due to shortage of food reserves in the rhizomes, a shortage which at the same time results in minimum capacity for regeneration in late spring to early summer. This minimum appears when primary shoots have developed 3-4 leaves and results in minimum tolerance to mechanical disturbance. According to studies in the UK (e.g. Leakey et al., 1978), rhizome buds can show two types of dormancy, a cyclical innate dormancy associated with the early summer season, as well as that due to apical dominance.

When the primary shoots of the plants or plant units have developed a foliage large enough for photosynthesis to compensate and increasingly exceed the consumption in the below-ground system, secondary tillers and new rhizome branches begin to develop from buds near or below the soil surface. In unshaded plants, this usually happens when the primary shoots have three to four foliage leaves. At this stage, or during a slightly extended period, the plants have a minimum regenerative capacity and are therefore more susceptible to mechanical disturbance by soil cultivation than earlier or later. The systemic effect of foliar herbicides is greater after application somewhat later, when the downward stream of assimilate is stronger and the foliage catching applied herbicides is larger in relation to the below-ground plant parts (Håkansson, 1967, 1969b, 1974, 1995).

Many of the aerial shoots established during the earlier part of the growing season, particularly the primary shoots, develop a culm by stem elongation. In many cases, a great proportion of the culms are sterile, but are otherwise similar to the spike-bearing ones.

Natural enemies

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Impact

Top of page E. repens is a competitive weed, being able to reduce growth and production in any crop, including competitive crops such as cereals. In the northernmost agricultural areas, e.g. in northern Scandinavia, it is frequently regarded as the economically most important weed. Many shoots of this grass are often still green when the crop is ripe. At mechanical harvest of cereals and other crops, these shoots can cause technical problems and result in yield losses. Hoeing in row crops is made difficult by rhizomes of E. repens in the soil.

In grassland and other crops grown for grazing, green forage, hay, etc., small amounts of E. repens may be harmless, if harvested in the younger stages when its shoots provide a qualitatively good feed (Teräsvouri, 1929). High proportions of E. repens are, however, always unfavourable in fodder crops stands because of a quantitatively low production.

Uses List

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Animal feed, fodder, forage

• Fodder/animal feed
• Forage

Environmental

• Erosion control or dune stabilization

Human food and beverage

• Spices and culinary herbs

Medicinal, pharmaceutical

• Traditional/folklore

Prevention and Control

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Due to the variable regulations around (de)registration of pesticides, your national list of registered pesticides or relevant authority should be consulted to determine which products are legally allowed for use in your country when considering chemical control. Pesticides should always be used in a lawful manner, consistent with the product's label.

Cultural Control

Cultural measures in the cropping system should always be considered. Measures improving the effect of competition in competitive crops such as small-grain cereals, oil-seed Brassica crops and many fodder crops are important. Using as small row spacings as is technically possible, and making all efforts to achieve an even distribution of the crop plants in the row, can reduce the plant growth of E. repens considerably, particularly in combination with a rapid and even emergence and establishment of the crop plants. To achieve rapid crop establishment, seedbed preparation and sowing depth adapted to soil type and climate are of the utmost importance (Håkansson, 1974, 1979, 1995). Systematic combination of techniques aimed at optimizing the competition from a potentially competitive crops, such as small grain cereals, may reduce the growth of E. repens by 50%.

Mechanical Control

Although considerable effects can be obtained by enhancing competition in certain crops, additional control is usually needed. When crops are harvested long before the end of the growing season, E. repens has its best period of rhizome production after harvest, in a period free of competition from the crop. Changing this period of production into reduction by mechanical or chemical control is a most effective measure in a control system for E. repens. When soil cultivation is carried out, the first operation (stubble cultivation) is preferably done immediately after harvest, with implements breaking the rhizomes as much as possible (Håkansson, 1968b; Boström and Fogelfors, 1999). When the growing period is long enough, operations are repeated at intervals. Ploughing is the last operation before winter or, on certain soils, it can be done in early spring if therew is enough time before the final seedbed preparation and sowing of the next crop. According to Håkansson (1974, 1982, 1995), combination of such tillage and competition in good stands of crops such as small-grain cereals will suppress E. repens and similar weeds by 90% or more.

Without effective tillage, E. repens, like other creeping perennial weeds, is hard to control sufficiently by any means except herbicides. This is illustrated in many experiments with reduced tillage in various forms (for example, Bachthaler, 1974; Cussans, 1976; Rydberg, 1992; Børresen and Njøs, 1994; Skuterud et al., 1996; Dzienia and Piskier, 1998).

Chemical Control

Where mechanical control is not desirable or not possible due to soil or climate, or for other reasons, different herbicides can be used for controlling grasses such as E. repens. Some of the more important ones are presented below.

A number of systemic foliar herbicides are effective on E. repens when the plants have sufficient actively growing aerial shoots in proportion to the attached rhizome system. The most important is glyphosate, a herbicide with low selectivity, used in a large number of countries with good effect in controlling E. repens. It is used in stubble fields after harvest, on fallow land, in orchards, on grassland in connection with ploughing (either before or following ploughing after sufficient time), in field margins and headlands, and in some countries, in ripe cereals e.g. by wiping or even spraying overall before harvest. Examples of other herbicides used for the control of E. repens are sethoxydime and cycloxydime, which are selective herbicides used in a number of dicotyledonous crops such as rape, turnip rape, beet, potatoes and peas. In recent years, other herbicides of this type, such as tepraloxydim (Kibler et al., 1999) have been used successfully in many of the crops mentioned. Foliar-applied herbicides of the sulfuro group may also be of interest for controlling E. repens, for example, sulfuron in potatoes (Kuzior et al., 1999), wheat (Rainbolt et al., 1999) and in fields of stubble (Rola et al., 2000). This and other herbicides of this group might attract an increasing interest in the control of E. repens in different cereals (e.g. Feucht et al., 1999). Various adjuvants are of interest for increasing the effect of sulfuron and other herbicides (Woznica et al., 1998). Among selective herbicides for soil application, EPTC has been used for several decades and is still used in some countries in dicotyledonous crops, e.g. in potatoes before planting. Propyzamide and terbacil are used in some countries, e.g. in orchards.

References

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Ahmed MT, 1980. Preliminary field observations on the preference of stem borers to different graminous host plants. Bulletin de la Societé Entomologique d'Egypte, 63:219-222.

Alex JF, 1982. Canada. In: Holzner W, Numata M, eds. Biology and Ecology of Weeds. The Hague, Netherlands: Dr. W. Junk Publishers, 309-331.

Australia; Tasmanian Department of Agriculture, 1977. Annual report for 1976-77. Annual report for 1976-77. Government Printer. Tasmania, No. 64:88 pp.

Bachthaler G, 1975. The development of the weed flora after several years' direct drilling in cereal rotations on different soils. Proceedings of the 12th British Weed Control Conference, Brighton, 1974, 1063-1071

Badowski M; Rola H, 1997. Occurrence and degree of hazard of grass weeds in crops in Poland. Progress in Plant Protection, 37:247-249.

Beddows AR, 1931. Seed setting and flowering in varioius grasses. Bull. Welsh Pl. Breed. Stn, Ser. H., 12:5-99.

Biniak B, 1983. Weed infestation of light soils with rhizomes of Agropyron repens (L.) P.B. during cereal rotations. Zeszyty Naukowe Akademii Rolniczej w Szczecinie, Rolnictwo, No. 31:3-11

Bor NL, 1960. The Grasses of Burma, Ceylon, India and Pakistan (Excluding Bambusae). Oxford, UK: Pergamon Press.

Borresen T; Njos A, 1994. The effect of ploughing depth and seedbed preparation on crop yields, weed infestation and soil properties from 1940 to 1990 on a loam soil in south eastern Norway. Soil & Tillage Research, 32(1):21-39

Bostr÷m U; Fogelfors H, 1999. Type and time of autumn tillage with and without herbicides at reduced rates in southern Sweden: 2. Weed flora and diversity. Soil & Tillage Research, 50(3/4):283-293; 39 ref.

Cussans GW, 1977. The influence of changing husbandry on weeds and weed control in arable crops. Proceedings, 1976 British Crop Protection Conference - Weeds. Volume 3., 1001-1008

Department of Agriculture; Western Australia, 1972. Summer weed competition in apple orchards. Annual Report 1971, 87.

Dzhyuba TP, 1992. Vegetation of dams of rice systems of the Black Sea area. Ukraïnskii Botanichnii Zhurnal, 49(3):31-35.

Dzienia S; Piskier T, 1998. Response of winter triticale to minimum soil tillage. Folia Universitatis Agriculturae Stetinensis, Agricultura, No. 69:29-32; 10 ref.

Ellenberg H, 1974. Zeigerwerte der Gefasspflanzen Mitteleuropas. Scripta Geobotanica 9. Gottingen: Goeltze.

EPPO, 2014. PQR database. Paris, France: European and Mediterranean Plant Protection Organization. http://www.eppo.int/DATABASES/pqr/pqr.htm

Feucht D; Mnller KH; Wellmann A; Santel HJ, 1999. BAY MKH 6561 - a new selective herbicide for grass control in wheat, rye and triticale. 1999 Brighton crop protection conference: weeds. Proceedings of an international conference, Brighton, UK, 15-18 November 1999., Volume 1:53-58; 1 ref.

Flora Europaea, 1964-80. Cambridge: Cambridge University Press.

Fontes FC; Fernandes JAD; Carvalho-Fontes F; Dias-Fernandes JA, 1977. Herbicides and chemical weed control. The viticultural, technological and economic interest of the use of herbicides in general and in strongly sloping vineyards. Bulletin de l'O.I.V, 50: 551, 33-42.

Gunnarsson GH, 1984. Grass species as weeds in Iceland. Nordisk Jordbrugsforskning, 66(2):165

Hakansson S, 1982. Multiplication, growth and persistence of perennial weeds. Biology and ecology of weeds [Holzner, W. and Numata, M. (Editors)] Dr. W. Junk The Hague Netherlands, 123-135

Holm LG; Pancho JV; Herberger JP; Plucknett DL, 1991. A Geographic Atlas of World Weeds. Malabar, Florida, USA: Krieger Publishing Company.

Holm LG; Plucknett DL; Pancho JV; Herberger JP, 1977. The World's Worst Weeds. Distribution and Biology. Honolulu, Hawaii, USA: University Press of Hawaii.

Hongo A, 1985. Seed productivity in Agropyron repens (L.) Beauv. collected from arable land. Weed Research, Japan, 30(2):137-142

Hskansson S, 1967. Experiments with Agropyron repens (L.) Beauv. I. Development and growth, and the response to burial at different developmental stages. Ann. agric. Coll. Sweden, 33: 823-873.

Hskansson S, 1969a. Experiments with Agropyron repens (L.) Beauv. IV. Response to burial and defoliation repeated with different intervals. Ann. agric. Coll. Sweden, 35: 61-78.

Hskansson S, 1969b. Experiments with Agropyron repens (L.) Beauv. VII. Temperature and light effects on development and growth. Ann. agric. Coll. Sweden, 35: 953-987.

Hskansson S, 1970. Experiments with Agropyron repens (L.) Beauv. IX. Seedlings and their response to burial and to TCA in the soil. Ann agric. Coll. Sweden, 36: 361-379.

Hskansson S, 1974. Kvickrot och kvickrotsbekampning pa aker. Uppsala: Lantbrukshogskolan. Konsulentavdelningen/Publikationer.

Hskansson S, 1979. Grundlaggande vaxtodlingsfragor. Uppsala: Swedish University of Agricultural Sciences, Department of Plant Husbandry, Report 72.

Hskansson S, 1995. Ogras och odling pa aker. Aktuellt fran lantbruksuniversitetet, 437/438. Uppsala.

Hunyadi K, 1979. Perennial weeds and their control on Hungarian state farms. Wissenschaftliche Beitrage der Martin-Luther-Universitat Halle-Wittenberg, No. 7 (S. 16):392-397

Johnson BG; Buchholz KP, 1962. The natural dormancy of vegetative buds on the rhizomes of quackgrass. Weeds, 10:53-57.

Ksmal S, 1989. Preliminary list of Chrysomelidae with notes on distribution and importance of species in Turkey. I. Subfamily Hispinp Gemminger & Harold. Turkiye Entomoloji Dergisi, 13(2):85-89

Kibler E; Landes M; Heyde Jvon der; Jahn D; Munger P, 1999. BAS 620 H-a new selective herbicide for post-emergence control of grass weeds in broadleaf crops. 1999 Brighton crop protection conference: weeds. Proceedings of an international conference, Brighton, UK, 15-18 November 1999., Volume 1:59-64.

Konstantinov KA; Nikolova V, 1983. Changes in the weed associations of the main vegetable crops. Gradinarska i Lozarska Nauka, 20(5):82-89

Korsmo E, 1925. Ugras I natidens jordbruk. Oslo: Cappelens.

Korsmo E, 1954. Ugras i nstidens jordbruk. Oslo, Norway: A-S Norsk Landbruks Forlag.

Kovacs J, 1983. Grass seed production in Western Hungary. A gyep vetomagtermesztese Nyugatmagyarorszagon. Agrartudomanyi Egyetem, Keszthely Hungary, 83pp.

Kuzior S; Spitalniak J; Pawinska M; Urbanowicz J, 1999. Sulfosulfuron use in potatoes. 1999 Brighton crop protection conference: weeds. Proceedings of an international conference, Brighton, UK, 15-18 November 1999., Volume 1:349-354; 6 ref.

Leakey RRB; Chancellor RJ; Vince-Prue D, 1978. Regeneration from rhizome fragments of Agropyron repens (L.) Beauv. 3. Effects of nitrogen and temperature on the development of dominance amongst shoots on multi-node fragments. Annals of Botany, 42(177):197-204

Mironenko AV; Khodortsov IR, 1978. The influence of herbicides on the productivity and quality of fodder lupin. Khimiya v Sel'skom Khozyaistve, 16(7):46-47

Neururer H, 1975. Changes in weed flora within the last 10 years in intensively used beet-growing districts of Austria because of modern agricultural practices. 3éme Reunion Internationale sur le Desherbage Selectif en Cultures de Betteraves, Paris, 1975, 375-388

Paichadze LV, 1974. Recovery, development and survival of wheat yellow rust in Georgia. Soobshcheniya Akademii Nauk Gruzinskoi SSR, 76(1):173-176

Palmer JH; Sagar GR, 1963. Biological flora of the British Isles. Agropyron repens (L.) Beauv. (Triticum repens L.; Elytrigia repens (L.) Nevski). Journal of Ecology, 51: 783-794.

Paulech P, 1992. Characteristic of the fungus Tilletia controversa Kuhn and its new locality on dog's grass (Elytrigia Desv.). Ceska Mykologie, 46(1-2):131-137

Petrova OA, 1975. The polymorphism of Elytrigia repens (L.) Desv. and its chromosome number. Tsitologiya i Genetika, 9(2):126-128

Pintilie C; Chirila C, 1985. Weeds in agricultural crops (XIV). Couchgrass (Agropyron repens (L.) P.B.). Productia Vegetala, Cereale si Plante Tehnice, 37(2):41-44

Rainbolt CR; Sanders SM; Thill DC; Christianson K, 1999. Qackgrass control in wheat with sulfosulfuron. Proc. Western Soc. Weed Sci., Colorado Springs, Colorado, 52:59.

Rola H; Rola J; Badowski M; Haas HU, ed. , Hurle K, 2000. Regrowth of rhizomes of E. repens (L.) Gould after herbicide application. Proc. 20th German Conference on Weed Biology and Weed Control. Stuttgart-Hohenheim, Germany. Pflanzenkrankheiten und Pflanzenschutz. Sonderh., 17:607-612.

Rola J, 1985. The threat of Agropyron repens to field crops and the effectiveness of control measures. Materiay Sesji Naukowej Instytutu Ochrony Roslin, No.25:115-130

Rola J; Rola H, 1994. Chemical control of Agropyron repens and dicotyledonous weeds in maize cultivation technology without ploughing. Materiay Sesji Instytutu Ochrony Roslin, 34(1):90-95

Rydberg T, 1992. Ploughless tillage in Sweden. Results and experiences from 15 years of field trials. Soil & Tillage Research, 22(3-4):253-264

Saakyan GS; Dolukhanyan SD; Esayan GL, 1981. Effectiveness of dalapon on denuded grasslands. Trudy Nauchno-issledovatel'skii Institut Pochvovedeniya i Agrokhimii Armyanskoi SSR, No.15:180-185

Sapru BL; Raina R, unda. Weed dynamics in orchards of Kashmir valley. Abstracts of papers, annual conference of Indian Society of Weed Science, 1985, 97-98

Skuterud R; Semb K; Saur J; Mygland S, 1996. Impact of reduced tillage on the weed flora in spring cereals. Norwegian Journal of Agricultural Sciences, 10(4):519-532; 20 ref.

Stach J, 1992. Soil cultivation in relationship to the development of weeds. Rostlinna Vyroba, 38(7):589-593

Sturny WG; Zanoni U; Keller ER, 1984. Long-term effects of crop rotations, fertilizers and herbicide treatments on the weed flora. Zeitschrift fur Pflanzenkrankheiten und Pflanzenschutz, Sonderheft 10:41-50

Takabayashi M, 1981. Ecology and distribution of upland weeds in Japan. Proceedings of the Eighth Asian-Pacific Weed Science Society Conference., 207-208

Terasvuroi K, 1929. Die Quecke, Triticum repens L., als Kulturpflanze und Unkraut. Acta Agralia Fennica, 18. Helsinki.

Vysniauskas J; Tindziulis A, 1987. Combating weeds in the system of autumn soil cultivation. Lietuvos Darbo Raudonosios Veliaos Ordino Zemdirbystes Mokslino Tyrimo Instituto Darbai, Agronomija, No. 35:37-49

Wedin DA; Tilman D, 1996. Influence of nitrogen loading and species composition on the carbon balance of grasslands. Science (Washington), 274:1720-1723; 37 ref.

Wein RW; Wein G; Bahret S; Cody WJ, 1992. Northward invading non-native vascular plant species in and adjacent to Wood Buffalo National Park, Canada. Canadian Field-Naturalist, 106(2):216-224

Williams ED, 1968. Preliminary studies of germination and seedling behaviour in Agropyron repens (L.) Beauv. and Agrostis gigantea Roth. In Proceedings of the 9th British Weed Control Conference, 119-124.

Williams ED, 1970. Studies on the growth of seedlings of Agropyron repens (L.) Beauv. and Agrostis gigantea Roth. Weed Research, 10: 321-330.

Williams ED; Attwood PJ, 1971. Seed production of Agropyron repens (L.) Beauv. in arable crops in England and Wales in 1969. Weed Research, 11: 22-30.

Woznica Z; Milkowski P; Kuzior S; Spitalniak J, 1998. Effect of adjuvants on the herbicide Apyros 75 WG (sulfosulfuron) efficacy. Progress in Plant Protection, 38(2):692-694; 2 ref.

Yinon Y; Pnuel Y; Shiffer O; Rosenberg U, 1985. The control of couchgrass in the Negev by application of Roundup in the fallow year preceding winter cereals. Hassadeh, 65(10):1958-1961

Zerova MD; Seregina LYa, 1991. Chalcids of the genus Eridontomerus (Hymenoptera, Torymidae) of the fauna of the USSR. Zoologischeskii Zhurnal, 70(6):141-144

Distribution References

Ahmed M T, 1980. Preliminary field observations on the preference of stem borers to different graminous host plants. Bulletin de la Societe Entomologique d'Egypte. 219-222.

Alex J F, 1982. Canada. In: Biology and ecology of weeds [Holzner, W. and Numata, M. (Editors)], The Hague, Netherlands: Dr. W. Junk. 309-331.

Badowski M, Rola H, 1997. Occurrence and degree of hazard of grass weeds in crops in Poland. (Występowanie i stopień zagrożnia jednoliściennymi gatunkami chwastów upraw polowych w Polsce.). Progress in Plant Protection. 37 (2), 247-249.

Bor NL, 1960. The Grasses of Burma, Ceylon, India and Pakistan (Excluding Bambusae)., Oxford, UK: Pergamon Press.

CABI, Undated. Compendium record. Wallingford, UK: CABI

CABI, Undated a. CABI Compendium: Status as determined by CABI editor. Wallingford, UK: CABI

Dzhyuba T P, 1992. Vegetation of dams of rice systems of the Black Sea area. Ukraïnskiĭ Botanichniĭ Zhurnal. 49 (3), 31-35.

EPPO, 2014. EPPO Global database (available online). Paris, France: EPPO. https://gd.eppo.int/

EPPO, 2020. EPPO Global database. In: EPPO Global database, Paris, France: EPPO.

Fontes F C, Fernandes J A D, 1977. Herbicides and chemical weed control. The viticultural, technological and economic interest of the use of herbicides in general and in strongly sloping vineyards. (Herbicides. Methode de desherbage chimique. Interet viticole, technologique et economique de l'emploi des herbicides en general et dans les vignobles a forte pente.). Bulletin de l'O.I.V. 50 (551), 33-42.

Gunnarsson G H, 1984. Grass species as weeds in Iceland. (Græsarter som ukrudt i Island.). In: Nordisk Jordbrugsforskning, 66 (2) 165.

Holm L G, Pancho J V, Herberger J P, Plucknett D L, 1991. A geographic atlas of world weeds. Malabar, Florida, USA: Krieger Publishing Co. 391 pp.

Holm L G, Plucknett D L, Pancho J V, Herberger J P, 1977. The world's worst weeds. Distribution and biology. Honolulu, Hawaii, USA: University Press of Hawaii. 610 pp.

Hongo A, 1985. Seed productivity in Agropyron repens (L.) Beauv. collected from arable land. Weed Research, Japan. 30 (2), 137-142.

Hunyadi K, 1979. Perennial weeds and their control on Hungarian state farms. Wissenschaftliche Beitrage der Martin-Luther-Universitat Halle-Wittenberg. 392-397.

Konstantinov K A, Nikolova V, 1983. Changes in the weed associations of the main vegetable crops. Gradinarska i Lozarska Nauka. 20 (5), 82-89.

Korsmo E, 1954. Ugras i nstidens jordbruk. Oslo, Norway: A-S Norsk Landbruks Forlag.

Mironenko A V, Khodortsov I R, 1978. The influence of herbicides on the productivity and quality of fodder lupin. Khimiya v Sel'skom Khozyaistve. 16 (7), 46-47.

Neururer H, 1975. Changes in weed flora within the last 10 years in intensively used beet-growing districts of Austria because of modern agricultural practices. In: 3e Reunion Internationale sur le Desherbage Selectif en Cultures de Betteraves, Paris, 1975. [3e Reunion Internationale sur le Desherbage Selectif en Cultures de Betteraves, Paris, 1975.], 375-388.

Paichadze L V, 1974. Recovery, development and survival of wheat yellow rust in Georgia. (Vozobnovlenie, razvitie i sokhranenie zheltoi rzhavchiny pshenitsy v Gruzii.). Soobshcheniya Akademii Nauk Gruzinskoi SSR. 76 (1), 173-176.

Paulech P, 1992. Characteristic of the fungus Tilletia controversa Kühn and its new locality on dog's grass (Elytrigia Desv.). (Charakteristika huby Tilletia controversa Kühn a jej novej lokality na pýre (Elytrigia Desv.).). Česká Mykologie. 46 (1-2), 131-137.

Petrova O A, 1975. The polymorphism of Elytrigia repens (L.) Desv. and its chromosome number. Tsitologiya i Genetika. 9 (2), 126-128.

Pintilie C, Chirilă C, 1985. Weeds in agricultural crops (XIV). Couchgrass (Agropyron repens (L.) P.B.). (Buruienile din culturile agricole (XIV). Pirul tîrîtor (Agropyron repens (L.) P.B.).). Producția Vegetală, Cereale și Plante Tehnice. 37 (2), 41-44.

Rola J, Rola H, 1994. Chemical control of Agropyron repens and dicotyledonous weeds in maize cultivation technology without ploughing. (Chemiczne zwalczanie perzu właściwego (Agropyron repens) i chwastów dwuliściennych w bezorkowej technologii uprawy kukurydzy.). Materiały Sesji Instytutu Ochrony Roślin. 34 (1), 90-95.

Saakyan G S, Dolukhanyan S D, Esayan G L, 1981. Effectiveness of dalapon on denuded grasslands. Trudy Nauchno-issledovatel'skiĭ Institut Pochvovedeniya i Agrokhimii Armyanskoĭ SSR. 180-185.

Stach J, 1992. Soil cultivation in relationship to the development of weeds. (Zpracování půdy ve vztahu k rozvoji plevelů.). Rostlinna Vyroba. 38 (7), 589-593.

Sturny W G, Zanoni U, Keller E R, 1984. Long-term effects of crop rotations, fertilizers and herbicide treatments on the weed flora. (Langjähriger Einfluss von Fruchtfolge-, Düngungs- und Unkrautbekämpfungsmassnahmen auf die Zusammensetzung der Unkrautflora.). In: Zeitschrift für Pflanzenkrankheiten und Pflanzenschutz, 41-50.

Takabayashi M, 1981. Ecology and distribution of upland weeds in Japan. In: Proceedings of the Eighth Asian-Pacific Weed Science Society Conference. [Proceedings of the Eighth Asian-Pacific Weed Science Society Conference.], 207-208.

Vyšniauskas J, Tindžiulis A, 1987. Combating weeds in the system of autumn soil cultivation. (Piktžolių naikinimas rudeninio žemės dirbimo metu.). Lietuvos Darbo Raudonosios Vėliaos Ordino Žemdirbystės Mokslino Tyrimo Instituto Darbai, Agronomija. 37-49.

Wein R W, Wein G, Bahret S, Cody W J, 1992. Northward invading non-native vascular plant species in and adjacent to Wood Buffalo National Park, Canada. Canadian Field-Naturalist. 106 (2), 216-224.

Yinon Y, Pnuel Y, Shiffer O, Rosenberg U, 1985. The control of couchgrass in the Negev by application of Roundup in the fallow year preceding winter cereals. Hassadeh. 65 (10), 1958-1961.

Zerova M D, Seregina L Ya, 1991. Chalcids of the genus Eridontomerus (Hymenoptera, Torymidae) of the fauna of the USSR. Zoologischeskiĭ Zhurnal. 70 (6), 141-144.

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