I’ve always thought that learning to recognise plants during winter is useful. It’s only really possible when herbaceous plants (green-stemmed, not woody), have got a head start in autumn. It’s a great way to recognise leaf shapes and plant structure – plus, you’ll be able to watch as it grows and flowers.
In this article, I’ll be exploring a few common species along the base of hedgerows. You’ll find out how to identify them, as well as what these species indicate in terms of the delicate balance of the natural world (or more specifically, how we’re affecting it).
A Lincolnshire hedgerow
Here’s a shot of a fairly typical hedgerow base in the Lincolnshire Wolds. It was taken at the beginning of January. As you can see, there’s a lot of green here. There are some years where in January you’re looking at largely bare earth and dead vegetation, but in 2022, due to a warm autumn, the perennial plants got a head start, before being stopped in their tracks by a cold spell in November.
It might just look like a mass of green, but there are five noteworthy plants visible in the shot here. All five of these plants are common along agricultural hedgerows.
Cleavers
The first is a cleaver (Gallium aparine). A member of the bedstraw family, this is a vigorous perennial plant with sticky stems and seeds. The plant is covered in tiny hooks – which makes it ‘stick’ to just about everything. It’s a very robust plant that can colonise all kinds of areas because it spreads so wildly, clings to other plants (out-competing them), and produces so many seeds. Cleaver isn’t particularly noted for its wildlife-friendliness, though it is a food plant for some caterpillars.
Cleaver
You can identify cleavers by the thin leaves, and square, creeping stems that soon bend as they grow and attach to just about anything. They’ll feel sticky to the touch. Mammals, birds, and dogs will unwillingly disperse this plant as the seeds attach to them easily.
Stinging and dead-nettles
The second two are nettles, but there’s a distinction. The first is the stinging nettle (Urtica diosica) and the second is the white dead-nettle (Lamium album). Despite both being ‘nettles’, they’re actually from different families. Stinging nettles are, predictably, from the nettle family (Urticaceae) whereas dead nettles are from the mint family (Lamiaceae).
Dead nettle and stinging nettle
Both of these plants are great for wildlife. The white dead-nettle in particular is very popular among long-tongued bees – it’s little wonder that some queen bumblebees nest in the base of hedgerows. It means her workers will emerge with a quick and easy source of food.
Dead-nettles are so-called because they don’t sting, and while it looks very similar to stinging nettle, there are a couple of differences. Without looking at the flowers, the most definitive difference is the stems: dead-nettles have square stems and stinging nettles have round ones. You could also try looking at the leaves. Sometimes (not always), you will find that the edges of dead-nettle leaves are slightly more rounded, whereas in stinging nettles they’re pointed.
Observing the flowers is another way. White dead-nettles have clusters of white ‘lipped’ flowers around the stem. The flowers on a stinging nettle are more subtle. They’re much, much smaller, and grow in denser clusters. They’re usually a green or off-white colour.
Stinging nettle is equally a beautiful plant. It’s a bit more vigorous than dead-nettle along these hedgerows, and of course, will sting you, but it’s the food plant for dozens of caterpillars.
Couch grass
The fourth plant is a grass widely considered to be a ‘problem’ grass because of its vigour. It’s called couch grass (Elytrigia repens). Couch grass is recognisable over other grasses due to its slightly fatter leaves, and its growth habit is distinctly clumpy. It can quickly form thick thatches and crowd out delicate plants. While it does need controlling, as with all plants it does support some wildlife, including some caterpillar species. If left to grow long enough, it may also protect insects and small mammals.
Couch grass
Cow parsley
The final plant in this picture is cow parsley (Anthriscus sylvestris). This is a common plant at the base of hedges and roadsides. It’s actually a member of the carrot family, and as such, you’ll notice the fern-like leaves are very similar to those of carrots
Cow parsley has delicate, but quickly growing leaves which kick off during late winter and early spring. It sends up spikes, at the top of which sit umbrella-like flower heads and creamy white flowers. It’s attractive to a huge number of wildlife species, from butterflies to hoverflies, and even some small mammals.
Cow parsley
Cow parsley can however be confused with some other members of the carrot family, including hemlock, which is very poisonous. So always take care when trying to identify it!
A common thread
So why are these five plants so common on hedgerows near farmland? Well, they LOVE nitrogen-rich soil. They thrive in it. Plants are sessile species (they stay in one place) but when seeds find their way into the ideal soil for the plant, they can quickly colonise the area, which is exactly what has happened in this nitrogen-heavy soil.
The soil at the base of hedgerows, particularly near farmland, is usually extremely rich in nitrogen, which helps with leaf development. The two main reasons for this are:
Management
Although there are small signs this is changing, hedgerows and their herbaceous ‘understoreys’ are managed in a way that creates constant nitrogen enrichment. When hedges and their plants are cut, the cuttings are often left behind. When this nitrogen-rich mulch decomposes nitrogen re-enters the soil, creating an endless cycle of nitrogen-rich soil. The same group of plants then grow happily, and even more vigorously as the cycle continues.
Farming practices
Intensive agriculture practices can generate large quantities of nitrogen that leach into neighbouring soils. Nitrogen-rich fertiliser is washed into the ground and finds its way to the margins of the farmland. The excretions razing cattle like cows also enrich soils with nitrogen.
The problem
In short, human interference has caused a soil imbalance which has resulted in a loss of biodiversity.
White dead-nettle is a bit of an exception on this list. It’ll do well in nitrogen-rich soil, but may be out-competed by the stinging nettle. If things were to remain as they are, it’d be ‘survival of the fittest’ and it’s likely that of the two, stinging nettle would win out. The concept of survival of the fittest is of course a cornerstone of evolution, but interfering with that process changes things.
Countless delicate plants have lost out to this cycle of vigorous nitrogen-fuelled growth, which has severely reduced species-richness in hedgerows. It’s one of the reasons Plantlife did a report called We need to talk about Nitrogen.
Plants like garlic mustard, birds-foot trefoil, and other wildflowers don’t really stand a chance in this environment and are quickly crowded out. It’s not that any of these plants can’t thrive in nitrogen-rich soil, but some plants just thrive more. This creates an abundance of only a few species of plant, with limited wildlife value, and is one of the many reasons we’re seeing biodiversity loss.
Plants like garlic mustard can be out-competed by more vigorous, nitrogen-loving plants. Photo by Kadir Celep on Unsplash
What we need to do
Like most of our most pressing environmental issues, the reality is we should have addressed this decades ago. We need to change the way we manage our land.
Hedgerow management
We need to cut hedgerows and verges less to prevent eutrophication (over-enriching with nutrients). If plants are left to ‘exhaust’ soil nutrients, other plants might stand a chance in what would be a more level playing field. Given the chance, more delicate plants will return to our hedgerows – though planting a few wildflowers as part of a community project isn’t a bad idea either.
Fertilisers
We also need to look at the use of nitrogen fertilisers, which are commonly used in intensive agriculture as a way to add nutrients to the soil. But it’s often because the land is so intensively farmed that fertilisers are needed in the first place. With two monoculture (single variety) crops a year, regular ploughing, and chemical use, soil health is depleted, meaning potentially higher applications of fertilisers are needed. With a third of the world’s soil now ‘highly degraded’, it’s not just wildlife at serious threat here, it’s food security for humans.
Monocultures like rapeseed regularly depletes the soil of the same nutrients / Photo by Etienne Girardet on Unsplash
The ‘organic’ solution
Organic farming is one of the best ways we can restore biodiversity to our farmlands. But, it’s not straightforward. Organic farming isn’t easy – and as inferred in my previous paragraph, some farmers are working with extremely nutrient-poor soil. As a result, they rely on fertilisers to get a decent crop for their efforts. It’s easy to try and blame farmers, but the situation requires empathy, and needs to be approached holistically. But, the fact remains that intensive, non-organic agriculture is destroying habitats, accelerating climate change, and depleting soil health and biodiversity. To address the problem, we not only need to look at farming but also global consumption, and where we buy our food from.
Step the heck up, government
The government can’t have it both ways. It cannot encourage the continuation of a capitalist system based on excessive consumption and not expect to see a degradation of the land. So a clearly laid out support package for farmers to less intensively manage their land is needed. There are schemes available, such as subsidies to grow nitrogen-fixing legumes (to restore soils). But with nitrogen fertiliser use remaining relatively unchanged, the offers aren’t being taken up. Just recently, the government announced that they will pay more to farmers who protect the environment, and time will tell what the uptake will be – and even if it all makes logical sense.
Final thoughts…
This is a nebulous topic that pretty much cuts across many of the major issues we’re facing as a global society. But, I hope I’ve gone some way to demonstrate what plants can tell us about the state of the environment. We need to enrich and enhance our landscapes to create beautiful habitats for wildlife otherwise we face our land being dominated by a few vigorous species. As a result, we face a future with diminished wildlife, which has far-reaching implications for humanity.
If you’d like to help, I’d always recommend getting in touch with your local council and understanding their environmental strategies, joining an environmental group, and – if you can – volunteering for community planting projects (or starting your own!)
All good wishes,
Lewis