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Hemerocallis Gall Midge – Contarinia quinquentata

Hemerocallis Gall Midge: Appearance, Territory, Damage and Life Cycle Latin Name: Contarinia Quinquenotata Appearance: Adults resemble tiny flies (3mm). They might be difficult to spot with the naked eye. The larvae are translucent and 3mm in size. They are hidden within flower buds and are often coupled with a watery liquid, making them difficult to spot. Gall-forming insects may typically be identified by the sort of gall they develop as well as the plant they infest. The larval feeding of this midge will result in aberrant blooming. In compared to healthy blossoms, galled flowers will be stumper and conical-shaped. Instead of the typical long and thin form, they become bloated, shorter, and thicker. Host Plant: Hemerocallis species and cultivars are the host plants of Hemerocallis gall midge. Territory: The Hemerocallis gall midges were discovered in the United Kingdom, and they have since spread throughout the country. The capacity of daylilies to produce healthy blooms can be harmed by the Hemerocallis gall midge. The midge, which was first introduced to the United Kingdom in 1989, is now prevalent in England and Wales, as well as in portions of Scotland. It was also discovered in British Columbia, Canada, in the summer of 2001. It has since crossed the border into Washington state, and AHS members in northern Ontario and Nova Scotia have recently reported it. Maine has also been reported to have this bug in 2019. Damage Caused: The larvae’s feeding activities inside the buds induce aberrant bud growth and failure to open meaning no flowers. The flower buds that are impacted decay on the plant or dry out before opening, resulting in no blooms. By early to mid-July, the damage had been done. A serious daylily bug that causes the buds to enlarge and fall off prior to blossoming. It can result in significant floral loss. Life Cycle and habits: The Hemerocallis gall midge is a tiny fly – or midge – in adulthood. In May and June, female flies lay their eggs in the growing flower buds of daylilies. These eggs hatch into larvae that feed on the insides of the buds, resulting in aberrant flower growth. Each flower bud has hundreds of them. As they eat, a watery liquid forms inside the bud, making the larvae difficult to see. When the larvae are sufficiently nourished, they fall into the earth and spend the winter within silk cocoons. In May-June, adult midges emerge, and the lifecycle begins all over again. Each year, there is just one generation.