Posts Tagged ‘Species’

About Parthenium Parthenium is an invasive weed which has multiple negative impacts – on human and animal health as well as crop yields and biodiversity. Parthenium grows during the spring and summer months, between April and November. It grows rapidly to a height of around 1.5 metres and spreads its seeds far and wide. Each…

Why use biocontrol? It is in all our interests that damaging invasive non-native species are not released into the wild. The priority of the government’s non-native species secretariat is to ensure the public understands the risks of introducing these species. However, where an invasive non-native species is concerned, we need to consider control and the…

The problem Native to the Americas and introduced in the 1980s through the ornamental aquatic trade, floating pennywort (Hydrocotyle ranunculoides) is a strong contender for the title of worst aquatic weed in the UK, having spread rapidly from garden ponds into our waterways. Since 2014, it has been banned from sale. It is also illegal…

The problem Native to the Americas, Azolla filiculoides was introduced to the UK in the 19th century and became naturalized, going on to become widespread on slow moving and stationary water bodies, frequently infesting valuable or threatened habitats. Azolla can have a variety of impacts: it can reduce light and oxygen reaching submerged flora and…

The problem Australian swamp stonecrop (Crassula helmsii) is an invasive aquatic plant that dominates still and slow-flowing waterbodies. It was initially introduced from Australia in the early 1900s as a garden pond plant but is now spreading across waterbodies in the UK and parts of Western Europe. It is particularly problematic in sensitive aquatic habitats…

The problem Japanese knotweed (Fallopia (= Reynoutria) japonica) is a highly invasive species in the UK, mainland Europe, North America and parts of Oceania. Since it was introduced as a prized ornamental from Japan in the mid-19th century, the species has become problematic in its entire exotic range where it has established, with detrimental impacts…

The problem Himalayan balsam (Impatiens glandulifera) has rapidly become one of the UK’s most invasive weed species, colonising river banks, waste ground and damp woodlands. It successfully competes with native plant species for space, light, nutrients and pollinators, and excludes other plant species, thereby reducing native biodiversity. As an annual plant, Himalayan balsam dies back…