Lolium arundinaceum

Tall fescue is a long-lived tuft-forming perennial with erect to spreading hollow flowering stems up to about tall (exceptionally up to 200 cm) which are hairless (glabrous), including the leaf sheaths, but with a short (1.5 mm) ligule and slightly hairy (ciliate) pointed auricles that can wrap slightly around the stem. The leaf blade is flat, up to about 10 mm wide, and also glabrous, but rough on both sides and the margins. The tillers (non-flowering stems) are typically shorter but otherwise similar to the culms. The leaves have prominent veins running parallel the entire length of the blade. Emerging leaves are rolled in the bud (convolute vernation). Note that most grasses are folded not rolled, which make this a key identification feature on tall fescue. Flowering typically occurs from early June until late August, with an erect to slightly nodding open panicle up to about long. The branches are normally in pairs, each of which has 3-18 spikelets, which are 9–15 mm long and comprise 4-8 bisexual florets and two short, unequal glumes. The lower glume has only 1 nerve whereas the upper one has 3. The lemmas typically have a short (3 mm) awn arising just below the tip. Each floret has 3 stamens with anthers about 3–4 mm long. The fruit is a nut or caryopsis with the seed tightly enclosed by the hardened lemma and palea. ==Taxonomy==

Tall fescue was first described (as Festuca arundinacea) by the German naturalist Johann Christian Daniel von Schreber in 1771. Its inclusion within the genus Festuca was due to the similarity of the flowers and inflorescences. However, there has been much debate since 1898 about its relationship to the genus Lolium, largely because of hybridization with Lolium perenne (species in separate genera are far less likely to form hybrids than those within the same genus). Recent DNA studies have shown that it should indeed be considered a ryegrass (Lolium) rather than a fescue (Festuca) because these species are more closely related to each other, despite the fact that ryegrasses have inflorescences of spikes rather than panicles. Its chromosome number is 2n = 42. ==Distribution and status==

The cultivated species has become a common sight in California grasslands and habitats, such as the California coastal prairie plant community, since its introduction this species has been a topic of debate. ==Habitat and ecology==

In its native European environment, tall fescue is found in damp grasslands, river banks, and coastal areas. The British National Vegetation Classification lists it as a minor component in a range of grassland types, but it is particularly characteristic of its own MG12 Festuca arundinacea community, which is a tussocky type of pasture that occurs in brackish grazing marshes around the south and west coasts. This vegetation type is also home to some uncommon plants such as parsley water-dropwort and slender spike-rush. Tall fescue is also found in a number of salt marsh and maritime cliff communities. In New Zealand, where it is introduced, the species is particularly prolific in salt marshes, where it is often dominant. Native to Europe, tall fescue has established itself in introduced regions like North America, where it thrives in habitats such as grasslands, wetlands, riparian corridors, and marshy landscapes. Endophyte association Tall fescue can be found growing in most soils of the southeast including marginal, acidic, and poorly drained soils and in areas of low fertility, and where stresses occur due to drought and overgrazing. These beneficial attributes are now known to be due in part to a symbiotic association with the fungus Epichloë coenophiala,(formerly Neotyphodium coenophialum). This association between tall fescue and the fungal endophyte is a mutualistic symbiotic relationship (both symbionts derive benefits from it). The fungus remains completely intercellular, growing between the cells of the aboveground parts of its grass host. The fungus is asexual, and is transmitted to new generations of tall fescue only through seed, a mode known as vertical transmission. The tall fescue–endophyte symbiosis confers a competitive advantage to the plant. Endophyte-infected tall fescue compared to endophyte-free tall fescue deters herbivory by insects and mammals, bestows drought resistance, and disease resistance. In return for shelter, seed transmission, and nutrients the endophyte produces secondary metabolites. These metabolites, namely alkaloids, are responsible for increased plant fitness. Alkaloids in endophytic tall fescue include 1-aminopyrrolizidines (lolines), ergot alkaloids (clavines, lysergic acids, and derivative alkaloids), and the pyrrolopyrazine, peramine. s that can include methyl, formyl, and acetyl groups giving rise to different loline species. The lolines are the most abundant alkaloids, with concentrations 1000 higher than those of ergot alkaloids. Endophyte-free grasses do not produce lolines, and, as shown for the closely related endophyte commonly occurring in meadow fescue, Neotyphodium uncinatum, the endophyte can produce lolines in axenic laboratory culture. However, although N. coenophialum possesses all the genes for loline biosynthesis, it does not produce lolines in culture. ==Uses==

Tall fescue was introduced into the United States in the late 19th century, but it did not establish itself as a widely used perennial forage until the 1940s. As in Europe, tall fescue has become an important, well-adapted cool season forage grass for agriculture in the US with many cultivars. In addition to forage, it has become an important grass for turf and soil conservation. Tall fescue is the most heat tolerant of the major cool season grasses. Tall fescue has a deep root system compared to other cool season grasses. This non-native grass is well adapted to the "transition zone" Mid-Atlantic and Southeastern United States and now occupies over . In addition to serving as forage and turf grass, tall fescue is sometimes planted to stabilize soil, benefiting from its robust root network and adaptability to different environments. The predominant cultivar found in British pastures is S170. ==Endophyte infected tall fescue effects on animals==

Broodmares and foals Horses are especially prone to reproductive problems associated with tall fescue, often resulting in death of the foal, mare, or both. Horses which are pregnant may be strongly affected by alkaloids produced by the tall fescue symbiont. Broodmares that forage on infected fescue may have prolonged gestation, foaling difficulty, thickened placenta, or impaired lactation. In addition, the foals may be born weakened or dead. To moderate toxicosis, it is recommended that pregnant mares should be taken off infected tall fescue pasture for 60–90 days before foaling as late gestation problems are most common. Cattle Fescue toxicity in cattle appears as roughening of the coat in the summer and intolerance to heat. Cattle that graze on tall fescue are more likely to stay in the shade or wade in the water in hot weather. In the winter, a condition known as "fescue foot" might afflict cattle. This results from vasoconstriction of the blood vessels especially in the extremities, and causes a gangrenous condition. Untreated, the hoof might slough off. Additionally, cattle may experience decreased weight gains and poor milk production when heavily grazing infected tall fescue pasture. To deter toxicosis cattle should be given alternative feed to dilute their infected tall fescue intake. ==Nutrient pools under tall fescue pasture==

Carbon cycling in terrestrial ecosystems is a major focus of research. Terrestrial carbon sequestration is the process of removing carbon dioxide from the atmosphere via photosynthesis and storing this carbon in either plant or soil carbon pools. Increases in soil organic carbon help aggregate the soil, increase infiltration, reduce erosion, increase soil fertility, and act as long lived pools of soil carbon. Many studies have suggested that long term endophyte-infected tall fescue plots increase soil carbon storage in the soil by limiting the microbial and macrofaunal activity to break down endophyte infected organic matter input and by increasing inputs of carbon via plant production. While the long-term studies tend to show an increase in carbon storage, the short-term studies do not. However, short-term studies have shown that the endophyte association results in higher above- and belowground plant biomass production compared to uninfected plants, Site-specific characteristics, such as management and climate, need to be further understood to realize the ecological role and potential benefits of tall fescue and the endophyte association as it relates to carbon sequestration. ==Novel endophytes==

New cultivars are being bred and tested every year. A major focus of research is producing endophyte-infected tall fescue cultivars that have no detrimental effects to livestock while keeping the endophytic effects of reduced insect herbivory, disease resistance, drought tolerance, and extended growing season. Novel endophytes, also referred to as "friendly" endophytes, are symbiotic fungi that are associated with tall fescue, but do not produce target alkaloids in toxic concentrations. A widely used and tested novel endophyte is called MaxQ and is grown in the tall fescue grass host Georgia-Jesup. This cultivar of tall fescue-novel endophyte combination produces ergot alkaloids at near zero levels while maintaining the concentration of other alkaloids. ==See also==