![]() As part of the Global Urban Evolution Project (GLUE) scientists from 26 countries examined the production of cyanide by over 110,000 clover plants from 160 cities. White clover has been used as a model organism for global research into ecology and urban evolution. It is native in Europe and Central Asia, ubiquitous throughout the British Isles, introduced in North America, South Africa, Australia, New Zealand, Japan and elsewhere, and globally cultivated as a forage crop. However, one can, but only sometimes, possess four or more leaflets. Almost always, a white clover will be trifoliolate. The leaves form the symbol known as shamrock. The stems function as stolons, so white clover often forms mats, with the stems creeping as much as 18 cm (7 in) a year, and rooting at the nodes. The leaves are trifoliolate, smooth, elliptic to egg-shaped and long-petioled and usually with light or dark markings. The flowers are mostly visited by bumblebees and often by honey bees. The heads are generally 1.5–2 centimetres ( 1⁄ 2– 3⁄ 4 in) wide, and are at the end of 7 centimetres ( 2 + 3⁄ 4 in) peduncles or inflorescence stalks. It is low growing, with flowering heads of whitish florets, often with a tinge of pink or cream that may come on with the aging of the plant. The species name, repens, is Latin for "creeping". The genus name, Trifolium, derives from the Latin tres, "three", and folium, "leaf", so called from the characteristic form of the leaf, which almost always has three leaflets ( trifoliolate) hence the popular name " trefoil". The term 'white clover' is applied to the species in general, 'Dutch clover' is often applied to intermediate varieties (but sometimes to smaller varieties), and 'ladino clover' is applied to large varieties. The species includes varieties often classed as small, intermediate and large, according to height, which reflects petiole length. ![]() It has been widely introduced worldwide as a forage crop, and is now also common in most grassy areas ( lawns and gardens) of North America, Australia and New Zealand. It is native to Europe, including the British Isles, and central Asia and is one of the most widely cultivated types of clover. Trifolium repens (from Latin repens, meaning crawling), the white clover, is a herbaceous perennial plant in the bean family Fabaceae (otherwise known as Leguminosae). ![]() Trifolium occidentale Coombe, syn of subsp.Trifolium orphanideum Boiss., syn of var.Trifolium orbelicum Velen., syn of var.Trifolium nevadense Boiss., syn of var.Trifolium macrorrhizum Boiss., syn of subsp.Please refer to the most recent Alfalfa Insect Management Guide for specific control options. Chemical control measures are justified when infestations average 5 or more healthy larvae per crown. They are often kept under control by a naturally occurring fungus and a parasitoid wasp. Management Options: Clover leaf weevils are generally not considered a problem, unless they are numerous enough to retard growth in the spring. Adults then emerge a few days later, usually feed for a few days, and then become inactive for most of the summer. Pupation takes place within an oval cocoon just beneath the surface of the soil or in debris near the base of the plants. When full grown they are just under a 1/2 inch in length, noticeably larger than larvae of the alfalfa weevil. The later instars also often have a pinkish color associated with the line down their back. During the day the larvae often hide in leaf litter around the crown of alfalfa plants. However, the clover leaf weevil larvae have a brown head capsule and feed on the lower parts of alfalfa plants, rather than having a black head capsule and feed on the upper tips of the alfalfa. Clover leaf weevil larvae look a lot like alfalfa weevil larvae in that both are green with a white line down the back. The young larvae from the fall-hatched eggs feed throughout the winter during mild periods and become full grown in late March to early May. Most eggs hatch in the fall, but some remain through the winter. A few weevils may overwinter and deposit eggs during mild days of winter or early spring. They lay yellow oval eggs around their host plants, usually in the fall. Adults resemble alfalfa weevils, but are three or more times as large. Life History: The adult is a brown weevil about 1/4 inch long with indistinct stripes on its back. Introduction: The clover leaf weevil, Hypera punctata (Fabr.), is a native of Europe, but has long been present in North America and is now established in most areas where clover and alfalfa are grown.
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