Category: Invasive Species

Invasive Species

Why Is Japanese Knotweed Listed As An Invasive Species?

Every homeowner and gardener in the UK agree that Japanese knotweed is undoubtedly one of the most invasive and menacing plants these days. It is no surprise that so many people are worried about this species due to its capability of growing almost anywhere at an incredibly quick rate. More importantly, it can be challenging and costly to eradicate it without the use of chemicals and expert’ support.

In its native country – Japan, the growth of Japanese knotweed can be kept under control by applying different types of insects, thus reducing its devastating impacts. However, the resistance force in the UK is simply not good enough to prevent it from proliferating. Over time, the plant might become extremely destructive and damaging to the ecosystem in your garden and property, not to mention surrounding houses. To understand more why the Japanese knotweed is so bad, keep reading to learn about its spread and growth.

Spread and growth of Japanese knotweed UK presence
One of the main things that make Japanese knotweed a nightmare for every homeowner and gardener in the UK is the speed with which it spreads and grows. More seriously, its roots might penetrate through brickwork or tarmac and compromise the foundations of your house. While the plant will die back to the ground level during the winter, it might shoot up nearly 20 cm, but between April and September it can shoot up by as much as 8 inches per day and reach over 80 inches in height.

The Japanese knotweed does not generate viable seeds, but it would spread through a system of the underground root, which would penetrate up to 160 inches deep and extend for approximately 275 inches. Cut plants and fragments would also result in new growth. So it is highly unlikely that you can eliminate it entirely by chopping or yanking the roots. Instead, you might need the help of professional service and toxic chemicals.

Why is Japanese knotweed listed as an invasive species?
The World Conversation Union lists the Japanese knotweed as one of the worst invasive plants in the world. Its invasive system of root and strong growth might damage architectural sites, retaining walls, paving, roads, flood defences, buildings, and concrete foundations. Also, it might lower the capacity of river channels in carrying water during a flood.

The Japanese knotweed is also a frequent coloniser of the temperate riparian ecosystems, waste places, and roadsides. It can form dense, thick colonies which entirely dominate any other species, making it one of the worst destructive exotics in many countries. The invasion of the species can be partially attributed to the tolerance of a wide range of soil salinity, pH, and types. Its rhizomes might survive a temperature of up to −35C or −31 F.…