An update on ongoing survey carried out to map and record the diverse and fascinating Urban Flora of Newcastle.
Since October last year, I’ve been busy recording for what I am loosely calling an Urban Flora of Newcastle – an in-depth account of the wild and naturalised plants growing within the city limits. With some 52 tetrads visited so far, some more than once, I think it is going rather well. Indeed, to date, a total of 598 species have been found growing in a seemingly wild state. A startling number of plants, and a lot to get your head around!
While I am far from done – I’ll need to visit 103 tetrads in multiple seasons – the process of surveying is already yielding some interesting results, and a few difficulties too. An update on some of these can be found below.
What exactly is urban?
What exactly constitutes an urban habitat? Is it is the presence of concrete, tarmac, or perhaps buildings? Is it the proportion of a tetrad or square occupied by man-made habitats vs natural ones? Who knows, but this is a question I have wrestled with quite a bit so far. It is for this reason that I have removed 43 tetrads from the present survey, particularly on the peripheries of the city but also including areas such as Gosforth Nature Reserve where the flora is altogether more natural. Some outliers remain, but only where greenspace is choked by urbanisation.
Trees pose a fairly unique problem with the origins of many mature specimens being questionable at best. For this reason, I have chosen to only include trees where there is clear evidence of natural spread. Saplings and suckers are far easier to assess. That said, mature trees in relic habitats have been included. Especially within the city’s wooded denes.
Shrubs pose a similar problem to trees and it is becoming clear that within the city, we have a tendency to plant a whole range of weird and wonderful bushes. For this reason, I taking an even more radical approach by ignoring any which look remotely suspicious. Still, despite this, there has been an awful lot to see as many species readily spread from planting schemes.
Plants in gardens are always going to be contentious but with plenty of disturbed ground and pavement cracks, gardens are a good habitat for a whole host of species. Few people plant Hairy Bittercress (Cardamine hirtsuta) for example. Occasionally, garden plants can also be seen spreading into lawns, walls, and nearby gardens. These are fair game.
A few discoveries so far
I wrote a little about urban cotoneasters in Newcastle here. What is quickly becoming clear with this difficult group is that there are plenty more out there to be discovered beside the usual Wall Cotoneaster (Cotoneaster horozontalis). After the first record for VC67 a few weeks back, Swedish Cotoneaster (Cotoneaster x suecicus) has turned up at more sites still. What else is out there to be discovered?
An odd find in Jesmond Dene recently was an expansive patch of Redwood-Sorrel (Oxalis oregana) on a wooded bank. This species hasn’t been recorded before in North East and likely stems from a historic introduction or perhaps a garden throw-out. It is native, as you might expect, to North America.
English Ivy (Hedera helix) is a common sight just about everywhere in the city. It wasn’t until recently, however, that I realised that many of these plants were not English Ivy at all. With its wider terminal lobe, green veining, and distinctive smell, Atlantic Ivy (Hedera hibernica) is no doubt hideously under-recorded. It is certainly common in several of the tetrads visited so far.
Newcastle’s changing flora
Canadian Fleabane (Erigeron canadensis) is a common sight in the city – in gardens, pavements, and ruderal patches. Its cousin, Guernsey Fleabane (Erigeron sumatrensis) is historically much rarer but surprisingly, is cropping up at more sites than expected often in great numbers.
Narrow-leaved Ragwort (Senecio inaequidens) is another species on the increase. Only a few years back, it was only really present at a few spots along the Tyne but is now appearing by roadsides (and within gardens) elsewhere in the city. Recently, I also encountered what could be a hybrid between this and the commoner Oxford Ragwort (Senecio squalidus) but alas, I will need to watch it throughout the summer. I live in hope!
Shrubs taking hold
Many of the shrubs beloved in urban planting schemes have an uncanny knack for escaping into the wild. Wilson’s Honeysuckle (Lonicera nitida) is a prime example, but similar trends are being seen albeit rarely in Leatherleaf Viburnum (Viburnum rhytidophyllum), Hybrid Coralberry (Symphoricarpos × chenaultii) and Laurustinus (Viburnum tinus). The latter of which seems to like brownfield land here in Heaton.
Following its lightning spread across Southern parts of the UK, Water Bent (Polypogon viridis) reached Newcastle only recently. This year alone, I have found in within gutters, roadsides, and even gardens in several squares around Heaton and Byker. I suspect it is far more widespread than the maps would have you believe…