Love Thy Non-Human Neighbour


At the start of 2020, just before the year had begun to reveal what was in store, I made an appointment with a local tree surgeon. I needed advice. The plot of land I’d started to live on was in a very overgrown state and, after living in London for over 20 years, I was no horticulturalist. The sight that greeted me every morning was getting overwhelming: thickets of scrubby trees, overrun borders, masses of brambles and a wild orchard covered everything. Recent high winds had uprooted two big old trees, narrowly missing my windmill. I met the tree surgeon on a wet and windy Saturday in January to see if I could avoid any further losses. He poked around the site, tut-tutting a lot, before announcing that I needed to eliminate, rip out, and potentially burn, all invasive and non-native plant and tree species. I was taken aback and alarmed by the violent turn our conversation had taken. 

“So, what is an invasive species?” 

I asked.

“Anything non-native,” 

came his reply. 

“What makes a tree or plant invasive?”

“They just are.”

He left soon after, annoyed by my questioning and obvious puzzlement at his proposal. Long after he’d gone “They just are” and ‘“What is an invasive species?” continued to float around my head. 

So I decided to find out for myself. 

The UK government’s Department for Environment, Food & Rural Affairs (DEFRA) classifies 36 species of “Invasive alien plants” and 30 species of “Invasive non-native (alien) animal” within the UK. These are of special concern due to their “Invasiveness [and] Ability to establish in several nations across Europe, including the UK”. DEFRA also states that “they cause severe problems for native UK plants and the environment.”


This terminology seems threatening yet vague – conjuring images more common in science fiction: HG Wells or ‘The Day of the Triffids’ style invasions; giant plants looming over our own, innocent, well behaved, here-since-the-ice-age wildlife.

It seems that economic costs are also part of the official concern. An environmental audit paper published by the UK Parliament in October 2019 states that “On average INNS [Invasive non-native species] cost the UK economy £1.8 billion per year, mainly affecting agriculture, forestry, horticulture, utilities, construction and transport infrastructure.”

The hostility and unquestioned vilification of certain species, as I had witnessed through the angry tree surgeon, is common in the UK. The grey squirrel and Muntjac deer are two frequent victims:


These are a selection of the more lurid offerings that I found splashed across tabloid front pages describing the very publicly maligned Muntjac deer and grey squirrels. Their crimes? Muntjac deer are blamed for traffic accidents, and grey squirrels stand accused of using up resources and spreading diseases among native red squirrels – contributing to the continued drop in numbers of this ‘cuter’ species.

By a strange twist of fate, both these non-natives were introduced into the UK by the same person – the 11th Duke of Bedford Herbrand Russell. In the 1890s, Russell amassed a vast collection of rare and foreign animals at his family seat, Woburn Abbey. DNA analysis undertaken by Imperial College London has shown that the UK’s grey squirrel population can, at least in part, be traced back to a group released by Russell in Regents Park, London. Similarly Woburn, which is today a stately home and safari park, was the site of Russell’s deliberate release of Muntjac deer into the neighbouring countryside. The deer’s ability to adapt rapidly to life in the UK has helped their population expand to today’s levels.

I decided to find out if my garden was harbouring any more of the ‘invasive aliens’ listed by DEFRA. I set up a waterproof motion-sensor camera (it was lockdown – and I had a lot of time on my hands!) and quickly spotted both grey squirrels and Muntjac deer hiding in the tangled overgrowth. The squirrels were trying to get into the peanut bird feeders and I discovered the Muntjac deer were responsible for the lack of runner beans in my vegetable plot. I also spotted pheasants, one which was so friendly that I ended up calling him Geoffrey and began feeding him grain.

The pheasant is a familiar sight in the UK countryside and has become a feature of traditional Christmas cards. However, this large and colourful bird is actually native to Asia and is bred in captivity in the UK for hunting. Up to 50 million pheasants are released into the wild each year but the pheasant is not on the invasive species list and no official data is available regarding the damage its presence may cause to local and rare bird populations. Without specific lobbying from landowners or other stakeholders to claim damage the pheasant won’t be placed into the ‘invasive’ category; however the government has recently had to introduce a game licensing scheme over the unlawful release of birds without due consideration to local biodiversity. This lack of consistency and reluctance to disrupt activities like hunting and shooting shows that the real priority seems to be preventing economic loss, rather than maintaining biodiversity.

The other invasive species I found growing in my garden was the Himalayan balsam, a bold and beautiful plant which can grow up to 3 meters tall. The plant has pink hooded bell flowers and is popular with bees and other pollinating insects. The Himalayan balsam is capable of spreading rapidly and has taken up residence along UK rivers, leading to concerns that the plant is crowding out native species and eroding riverbank soil. These concerns have seen the Royal Marines being brought in as volunteers to clear it from the River Otter in Devon, and a ‘rust fungus’ has been introduced from India and Pakistan as a biological control to prevent the plant’s spread. Local environment agencies have even held ‘balsam bashing’ parties, where people are encouraged to walk along riverbanks ripping out and destroying the plant.

Although the Himalayan balsam is now widely reviled, it was once a very popular greenhouse flower. Brought to the UK in 1839 from its native home between Kashmir and Uttarakhand in India, the plant was intended to appeal to a growing middle class – those who wanted the aristocracy’s hot house and orchid collections at a more affordable price. They were promoted as plants with ‘“herculean proportions” and praised for their rapid growth – the very same features that bring derision and demonisation in the UK 100 years later.

It’s time for a rethink of our attitudes towards these species. They aren’t ‘alien’ or ‘invasive’ – they were trafficked, deliberately brought to the UK through greed, ignorance and a lack of respect for non-human life: flora and fauna as traded commodities rather than co-partners in life and joint survival. 

There is urgent need to understand what can be learnt from these rapid adapters and to welcome them as species which are able to thrive in a shifting climate and landscape, to admire their ability to survive against the odds and to disrupt our human-centric planetary takeover. Our attempts to declare what is allowed and what is not, what is invasive and what is native, based on arbitrary points in a linear human timescale that bares no relationship to the ebb and flow of human and non-human migration is bizarre. Considering that attempts to manipulate and control the environment have led to near destruction, a cognitive reframing is needed. 

As this year slowly moves forward and I continue to learn to live on this wild plot of land, getting to understand and know it from observing and delighting in its ability to surprise, I won’t be uprooting and burning any so-called invasive species – I will be tending to and seeing the flora and fauna as welcome co-dwellers. As the sixth mass extinction is currently underway, very careful thought is needed before destroying anything. 

                                                                        Louize Harries