Many of us enjoy the River Chelt as it winds its way through Cheltenham. For some residents, however, the river is even closer to home, flowing directly past the bottom of their garden.
To help us better understand how riverside gardens can support wildlife, we spoke to Ed Noyes, a river restoration specialist and Conservation Officer with the Wild Trout Trust. Ed has spent many years working on rivers across the Severn catchment and has a particular interest in river ecology, fish populations and restoring healthy river habitats. He has also worked on the River Chelt itself and is passionate about helping people understand the important role rivers play for wildlife and communities alike.
In this guest article, Ed explains why the vegetation growing in and alongside the Chelt is so important, and shares some practical tips for anyone lucky enough to have the river running through or alongside their garden.
The Chelt encounters all manner of situations as it travels downstream, some of the most diverse as it passes through Cheltenham itself. There is a lot of human interaction with the river here, whether through the built environment, parkland or many gardens that are adjacent to the watercourse.
A key habitat feature that makes the wildlife and ecosystem of the Chelt tick is the vegetation growing in and along the river. And of course, if this is made up of native plants, this represents a whole range of wonderful plant species in their own right! However, vegetation tends to get managed and cut back along the river for a variety of reasons. Through Cheltenham, this may be for flood management purposes (vegetation is seen to hold water back), in parks so people can get near the river (obviously!), and along gardens because sometimes we see it as something we need to do – or for personal taste. Unfortunately, all this cutting removes essential river habitat or can happen at the wrong time, which then impacts wildlife. This can be especially true as garden maintenance increases in the summer. Lawns get cut and vegetation is trimmed as everything grows and gardens get
prepared for enjoyment over the summer months.
In this piece, we want to share some tips on how to manage vegetation along the river bank if you are lucky enough to have the Chelt at the bottom of the garden. Hopefully bringing some pointers in about plants growing in the channel will enhance your enjoyment of the river and wildlife watching over the coming months, too.
Here are the main reasons Chelt vegetation is so important, along with pictures to explain why…
Overhead!
On the bank top, low growing trees and shrubs along the river provide additional over head cover to the river, such as in the picture below. This is becoming an increasingly important habitat feature as hot periods during the summer become more intense and for longer. The branches create very important shade to the river, helping to keep the river cool, as much of our stream wildlife can’t survive in water that is too warm.
Even one low bush over the river can provide a local refuge to many creatures when the sun is beating down. If you have shrubs growing over the river, try and limit pruning to essentials, to maintain some of the beneficial shade. And encourage more shrubs or trees where suitable.
Along the bank
Mature vegetation such as grasses, rushes, flowering plants and shrubs growing along the face of the bank, or the bank top, will benefit the watercourse in more than a couple of ways.
One of the key features is it develops is lovely low-overhanging and trailing vegetation along the edge of the water. This is really important cover for fish, habitat for insects (aquatic invertebrates) and provides excellent additional shade along the river edge.
Also a fantastic habitat corridor and food source for insect pollinators, too.
If you have some of this vegetation developing on your river bank, you could let it grow, or if access to the waters edge is important, retain some areas rather than cutting it all back – you might be surprised what you see darting in and out from underneath it.
Hopefully a Chelt trout!
Along the channel edge
Emergent plant growth in the channel is especially important in the summer when river levels drop, as it naturally narrows the channel to maintain water depths and flow speeds required by aquatic life. The picture here shows an excellent example of this on the Chelt (coupled with the fully aquatic plants doing the same job).
Emergent vegetation along the edge of the watercourse is excellent habitat for dragonflies, damselflies, demoiselles and alder flies which climb the stems to hatch out. If there are water voles in the area, this is the type of habitat they will choose to be in. This type of vegetation will also protect banks from erosion as the vegetation takes the power out of flows as river levels rise.
Try and leave some space for these marginal plants (literally a ‘margin’ between lawn and river), which isn’t cut mown or strimmed. This is a diverse zone, where marginal plant species form a transition from those fully rooted in the water’s edge, those in the damp soils adjacent and those in slightly drier conditions slightly further back up the bank.
Who doesn’t love a yellow flag iris, brooklime, water forget-me-not or purple loosestrife?
In the channel
In channel vegetation is a super important habitat feature for a full range of aquatic invertebrates and fish. It provides essential ‘cover’ for all fish species, and as mentioned above, helps narrow the channel and maintain water depths in conjunction with marginal vegetation during the summer. River water-crowfoot, such as the patches in the picture below, is especially beneficial for invertebrates as the complex structure of fine leaves provides a huge range of habitat types and feeding opportunities.
If you do have a garden and see some of this growing, avoid the temptation to chop it! You may see a greater presence of ‘up-winged’ mayfly species due to the aquatic plants, such as the blue-winged olive dancing over the water of a summers evening as they mate and lay eggs, or moth-like caddis flies fluttering around. Both happily eaten by local resident bats!
And contrast with a heavily managed section….
The River Chelt is one of Cheltenham’s most important wildlife corridors. For those who live alongside it, even small changes in how vegetation is managed can make a real difference. By leaving a little more space for nature at the river’s edge, we can help create a healthier river for fish, insects, birds and all the other wildlife that depends on it.
Read more about the work The Wild Trout Trust have been doing on the River Chelt.
Find out about the work the Guardians of the River do year round to look after our river.
