Llanelli Naturalists Newsletter - September 1999 - No 64
Ian Morgan
Personally I like urban botanising. Apart from the ease of access and general convenience, a surprising range of escapes enliven the constantly changing and often ad hoc assemblages of native plants or long-established alien weed species. The purpose of the summary is to discuss some of these escapes, possibly pending a more comprehensive account of the weed flora at a later date.
Some plants of garden origin have managed to colonize urban or other habitats by seed - the Wallflower Cheiranthes cheiri is a familiar and long established example, and almost aboriginal populations can be seen in some of Llanelli's back-lanes such as behind College Hill, 22/513003. Red Valerian Centranthus ruber and the two species of Campanula (portenschlagiana and posharskyana: see Llanelli Nats. Newsl. 62: 8-9, 1997) have, likewise, invaded old walls. A rarer colonist was Winter Savory Satureja montana, 35 plants of which were found on an old wall (since repointed) at Bryn Avenue, Burry Port 22/453009 in March 1993. Sulphur Cinquefoil Potentilla recta occupies an old wall at Robinson Street. 22/507002, together with the hybrid ragwort Senecio x albescens, which is a cross between the garden Silver Ragwort S. cineraria and the ubiquitous Common Ragwort S. Jacobea. Some colonists 'leap' off these old Pennant Sandstone and mortar walls and are found as weeds in the back lanes themselves. Many of these plants (as with others in this account) can be expected, in time, to increase exponentially in the urban landscape and beyond. Examples would be the lady's mantle Alchemilla mollis in lanes at Coronation Road, College Hill and Glenalla Road; and Feverfew Tanacetum parthenium (in its various forms) at many localities. Other plants are seemingly still in the initial stage of escape, but can be again expected to increase further, for example Seaside Daisy Erigeron glaucus (notably at Pwll 22/484010 etc) and Mexican Fleabane Erigeron karvinskianus on a brick wall at Spowart Avenue 22/503010.
Planted trees and shrubs also self-seed in an urban setting. Cotoneasters such as C. horizontalis and C. sternianus are frequent, whilst the whitebeams Sorbus intermedia on colliery shale at Furnace SN 500013 and S. aria agg. on the part-demolished wall of Lloyd Street Chapel 22/504002 are other examples. A cultivar of Norway Maple Acer plantanoides is self-sown at Bigyn 21/514998. Flowering Nutmeg Leycesteria formosa is a native of India and China. It is a shrub which grows to about 5 feet and has white flowers with very noticeable pendent purple bracts, and its berries are eaten by birds and thus distributed from gardens into the wider countryside. It occurs, for example, in Stradey Woods but I have also noted it in woodlands away from built-up areas; this species can be expected to increase in our county.
Spores of the popular pot plant, Maidenhair Fern Adiantum capillus-veneris have managed to colonize damp wall mortar at Stepney Road, Pwll 22/486011 (C Lewis) and also a tomb wall at Carmel Chapel, Burry Port 22/458023. Presumably at the latter site, the spores of this fern must have come from a flower arrangement, but at Pwll they perhaps escaped out of a window?
The next category of escapes are not really escapes at all. They are exiles, banished and thrown-out of the garden, usually because of invasive growth. In this category would fall the superficially-similar Chicory Cichorium intybus (at, for example, Penallt 22/518004) and Common Blue-sow-thistle Cicerbita macrophylla, the latter growing in a mostly vegetative state at the base of a hedge at Peoples' Park 22/503003. Other plants in this assemblage of thugs include the rampageous 'garden yellow archangel' Lamiastrum galeobdolon ssp. argentatum (very attractive though with silvermarked leaves), Shasta Daisy Leucanthemum maximum (this giant daisy growing at Stradey 22/499008 and other places) and 'Aunt Eliza' Curtonus paniculata (at Furnace Pond 22/504022 and Bigyn Hill 21/514998). The last-named is a larger, more stately relative of the regularly thrown out and familiar Montbretia Crocosmia x crocosmiifolia. In contrast, the spurge Euphorbia characias, found in April 1997 on waste ground behind Robinson Street 21/508999, is rarely encountered as a discarded plant. Because they are so invasive, various Michaelmas daisies and Early Goldenrod Solidago gigantea are also commonly chanced upon.
Michaelmas daisies are frequently naturalised in the Llanelli area, most presumably having originated from garden throw-outs. Records include Aster versicolor from Erw-las, Llwynhendy 21/537994, Machynys 21/512979 and Pembrey 22/429010; Aster x salignus at Pembrey Harbour 22/437003 and Llangennech 22/561012 and Aster lanceolatus from near Graig College 22/488011 and Stradey 22/495013.
In spring, the robust flowers of hybrid bluebells Hyacinthoides non-scripta x H. hispanica are surprisingly frequent (eg Furnace, 22/503013), whilst the also blue flowers of another garden escape the forget-me-not Myosotis sylvatica are regularly seen. Grasses originating from bird-seed are occasionally encountered - such as Yellow Bristle-grass Setaria pumila growing on shingle at the edge of Sandy Water Park 22/495004 and no less than three species in a raised bed outside 'Burtons' in Stepney Street 22/506003 - Common Millet Paniceum mileaceum, Canary-grass Phalaris canariensis and Cockspur Echinochloa crus-galli.
A bird-sown plant was the attractive bramble Rubus lacinatus (with markedly cut leaves) found at the rear of Cedric Street 22/513002 in 1994. It was herbicided out of existence in 1998 when many of Llanelli's back lanes were thus treated. (A robust plant of the UK endemic and Nationally Scarce White Ramping Fumitory Fumaria capreolata subsp. babingtonii was similarly treated in July 1999 in a hedge in Station Road, Llangennech, this having been one of only 16 records for this species of conservation concern in Carmarthenshire. - RDP).
An example of a back lane flora - at the rear of Gower View, Llanelli 22/512015, Aug. 1993 is given below:
- Snow-in-summer Cerastium tomentosum*
- Butterfly Bush Buddleja davidii*
- Wall Cotoneaster Cotoneaster horizontalis
- Snapdragon Antirrhinum majus*
- Wallflower Cheiranthus cheiri*
- White Stonecrop Sedum album
- Ivy-leaved Toadflax Cymbalaria muralis*
- Annual Pearlwort Sagina apetala*
- Sweet Alison Lobularia maritima
* these are also frequent elsewhere in Llanelli.
A damp wall nearby had Mind-your-own-business Soleirolia soleirolii. This mat-forming, small-leaved plant is also reasonably frequently encountered around Llanelli.
The above account is only an indication of the interesting garden escapes or weed flora of Llanelli. Due to land reclamation - principally grassing over - Llanelli's 'urban commons' (a better phrase than wasteground) are being progressively reduced. Locally characteristic plants such as Wormwood Artemesia absinthium, Hoary Mustard Hirschfeldia incana, Black Horehound Ballota nigra, Wild Mignonette Reseda lutea and Perennial Wall-rocket DiplotaxIs tenuifolia are, alas, declining in a fashion commensurate to the loss of their habitat.
