With all the different knotweed, hogweed and bindweed varieties out there, sometimes it isn’t easy to see the wood from the trees.
The majority of these differently named plants are individual species with their own visual and growth characteristics. However, Japanese hogweed is one plant that has an alter ego – it is actually the same plant as Japanese knotweed.
In this blog, we’ll look into how you can correctly identify Japanese hogweed. Some plants are extremely invasive, others highly toxic, so it’s vital to be able to identify the troublesome varieties accurately.
The best way to correctly identify Japanese hogweed and other invasive plants is to contact an experienced professional like The Knotweed Specialists. Don’t risk a costly and damaging invasion – send us a WhatsApp image, and we’ll get back to you straight away.
Japanese Knotweed versus Giant Knotweed versus Giant Hogweed – What’s The Difference?
Before we look at how to identify each of these plants, let’s take a look at the similarities. First of all, they are all invasive species, and their control falls within UK environmental laws; it is illegal to plant in the wild, to dispose of waste in unlicensed facilities, and the plant must be controlled within your own boundaries, meaning neighbouring properties can prosecute if their land is affected by invasive plants that have spread from your land.
Japanese knotweed (hogweed) and Giant knotweed are very similar plants, although, as the name suggests – Giant knotweed is much bigger, reaching up to 4-5 metres tall! The leaves of the Giant knotweed can grow to some 40cm long. These invasive plants are not harmful to humans or animals.
Giant hogweed is very different to Japanese knotweed and Giant knotweed. Not only is it invasive, but it can cause severe irritation, blistering and burns if sap from the plant touches the skin. Giant hogweed is characterised by its thick, strong stem and umbrella-shaped flower. It is actually a member of the carrot family, although not edible at all. Giant hogweed is dangerous to humans and animals, and it’s wise to familiarise yourself with its features so that you can avoid coming into direct contact with the sap.
Japanese Hogweed – What Does It Look Like?
Many plants, like Bindweed, are mistaken for Japanese knotweed, and often Japanese knotweed is not recognised as the unruly plant it is. Here are some distinctive features of the Japanese knotweed plant that set it apart from the rest:
- Lush, spade-shaped leaves.
- Leaves grow alternately up the stem.
- Leaves are tinted with red veins.
- Tall, hollow stems growing to 2-3 metres in height.
- Light green stems with reddish specks.
- Creamy-white elongated flowers in late summer and early autumn.
- Leaves turn yellow and drop in the Autumn.
- Dies back in winter, leaving an abundance of bare brown canes.
- Rhizome underground root system, often partially visible in the winter.
The Knotweed Specialists are experts at tackling invasive plants. Our service begins with identifying the plant. We will then conduct a comprehensive survey and produce a management plan to treat, remove and dispose of your infestation effectively.
How to Eradicate Japanese Hogweed Successfully
The problem with Japanese hogweed is it’s extremely difficult to remove permanently. It grows at an extraordinary pace – up to 30cm per day in high season! Its stems multiply to form dense thickets that inhibit local plants and wildlife by blocking out sunlight, and its strong roots and strands can damage infrastructure and property as they plough through the space at top speed.
The plant has an underground system of rhizomes that grow even during the winter, supporting its invasive habit. And the rhizomes can spawn from just a tiny speck of waste to form new growth. It’s no wonder Japanese hogweed is considered to be one of the most destructive plants in the UK!
So…what’s the answer? There are two primary methods out there to tackle an invasion: ground excavation and a program of herbicide treatment. Because Japanese hogweed can spread so quickly, depreciating land and property as it goes, it is not recommended to tackle the problem yourself. It is advisable to instruct an experienced contractor who will survey your land and create a management plan to treat, remove and dispose of Japanese hogweed.
Typically, a management treatment plan will involve a schedule of monitoring for 3-5 years to check for re-growth. It’s worth remembering that Japanese knotweed can lie dormant underground for up to 20 years!
The Knotweed Specialists are PCA certified and have considerable experience tackling Japanese knotweed, Giant knotweed, Himalayan Balsam, Bamboo and Bindweed invasions nationwide. Don’t take chances if you think you may have an invasive species within your boundaries, call the experts and avoid costly mistakes.
