Monmouthshire
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Monmouthshire Monmouthshire soils vary considerably across the vice-county. The main arable areas are focussed along the M4 corridor and east of the River Usk up to the foothills of the Brecon Beacons. Large areas of the land are clay and impermeable soils with a band of free-draining soil between Abergavenny, Monmouth and Newport. Along the east boundary with Gloucestershire there are patches of limestone derived soil, around Chepstow and east of Monmouth. Historically, small-scale arable cultivation was a feature of the mixed farming in the area as shown by the 1930s land use survey which is considered a low point in arable cultivation. Growing crops will probably have increased during the World Wars in the 20th Century as there was a greater need to be more self-reliant, and the advent of herbicides and inorganic fertilisers in the mid 20th Century has led to an increase in crop production in some areas as weed control has improved. The good transport links and soils along the M4 corridor, the A40 and A449 through the vice-county has supported a concentration in cultivation with an estimated 26% increase in arable land between the 1930s and 1990s land use surveys. Monmouthshire is a rich vice-county with records of 20 out of 30 threatened plants. It is the only vice-county with populations of lesser quaking-grass Briza minor and it is a hotspot for stinking chamomile Anthemis cotula. Some of the records of the threatened arable plants are considerably old such as red hemp-nettle Galeopsis angustifolia, darnel Lolium temulentum, prickly poppy Papaver argemone and corn buttercup Ranunculus arvensis. There is one recent record of grass-poly Lythrum hyssopifolia from a market garden but it has not been found since. Both naturally occurring and sown populations of cornflower Centaurea cyanus and corn marigold Glebionis segetum are present in Monmouthshire. Other populations of threatened plants are known to occur on other habitats as well as arable land including henbane Hyoscyamus niger which has been found in a rubbish dump in Newport, weasel’s-snout Misopates orontium which is present along the road verges near Penpergwm and annual knawel Scleranthus annuus which has been found growing in a stone wall on a farm. A large amount of recording has been undertaken at the tetrad (2x2km squares) level in Monmouthshire, and as a consequence corn mint Mentha arvensis is well recorded compared to other vice-counties where only hectad (10x10km squares) have been recorded for this threatened species. Corn spurrey Spergula arvensis and field woundwort Stachys arvensis are also widespread across Monmouthshire and Wales is probably the hotspot for these plants across the UK which can be sparsely distributed elsewhere. Sixty-four tetrads have three or more threatened arable plants and should be targeted for suitable management practices. Monmouthshire has a large number of areas that qualify as Important Arable Plant Areas as they have good assemblages of arable plants. There are ten tetrads considered to be of National Importance and 29 considered to be of County Importance for arable plants. Many of these areas aren’t targeted for arable plant conservation measures and refinement of the targeting should be undertaken to encourage management measures for arable plants where land is under cultivation. This would help maintain the floral diversity of the farmland and support pollinating insects, farmland birds and small mammals. Monmouthshire was included in a study of arable land between 2009 and 2012, but it was not comprehensive and there have been no other rigorous surveys of arable land in the vice-county. New populations of threatened arable plants are still being found in the Monmouthshire with both cornflower and lesser quaking-grass records being added in recent years. Monmouthshire is such a rich vice-county for threatened arable plants with good assemblages that further surveys are recommended across the county as it is likely that new populations of threatened arable plants may be found and that good assemblages of arable plants will be identified. In turn these support much of our farmland wildlife including pollinating insects, farmland birds and small mammals. Monmouthshire 1933-1949 Arable Land Use The extent of arable land in the 1933-49 period across Monmouthshire was restricted to the lower lying land covering 6965 ha. In total, 340 tetrads out of 426 tetrads had arable land use present. The 1930s are considered a low point in arable land use and the coverage of cultivated land may have been historically much greater. Locations with little arable land include the uplands and valleys in the foothills of the Brecon Beacons and the Newport Levels and coast. Concentrations of arable land are present along the M4 corridor between Cardiff and Newport, the Usk valley between Newport and Chepstow and between Abergavenny, Monmouth and the vice-county boundary. Contains Ordnance © Cyfoeth Naturiol Cymru, Survey data © Crown 2014. © Natural Resources copyright and database Wales, 2014. right 2014. ± 5 km Monmouthshire 1979-1991 Arable Land Use Between the 1933-49 land use survey and 1979-1991 Phase 1 habitat survey of Wales there was a 26% increase in arable land use across Monmouthshire. This goes against the trend of a declining arable industry across Wales with the arable land decreasing in the majority of vice-counties. 9414 ha of arable land was identified in the Phase 1 habitat survey with cultivated parcels of land falling in 302 out of 426 tetrads. Thus, although arable land has increased it is more concentrated compared with arable land use in the 1930-40s. An increase in arable land in Monmouthshire may be due to the good transport links that the county has as well as favourable loamy soils for growing crops. However, the increase in arable land may also be coupled with an increase in agro-chemical use, herbicides and fertiliser applications, all of which affect the growth of threatened arable plants. There is less cultivated land in the foothills of the Brecon Beacons west of the A4042. However, concentrations of arable land use are present between Newport and Cardiff, the Usk and Monmouth valley, between the vice-county boundary, Abergavenny and Monmouth, around Devauden and along the M4 corridor between Newport and Chepstow including on the Newport Levels. Some of this land may be grass leys which were mapped as bare ground in the Phase 1 habitat survey. Contains Ordnance © Cyfoeth Naturiol Cymru, Survey data © Crown 2014. © Natural Resources copyright and database Wales, 2014. right 2014. ± 5 km Monmouthshire Soil Map The most common soils in Monmouthshire fall within the clay category and is the dominate substrate for 290 out of 426 tetrads. Sandy soils are the dominant soil type for 100 tetrads. In the south east of the vice-county along the border with Gloucestershire there is a seam of limestone bedrock. This has created some calcareous-based soils and lime is considered the dominant soil type for 20 tetrads. The other category is the dominant substrate for 16 tetrads. This includes deep peat soils that are present on commons and in upland areas as well as disturbed soils following any industrial activity. Contains Ordnance © Cyfoeth Naturiol Survey data © Crown Cymru, 2014. © Natural copyright and database Resources Wales, 2014. right 2014. ± 5 km Stinking Chamomile Anthemis cotula Monmouthshire is a hotspot for stinking chamomile in Wales with many records located on the arable fields between Abergavenny and Usk. The majority of these records have been found recently, post 2010 and suggests that there may be further populations in this area. There are historical records pre-1986 on the border of Monmouthshire and Herefordshire indicating that stinking chamomile has been known from the vice-county for a long period of time and that the species is not a new addition through sown seed mixtures. There are records of stinking chamomile that fall into the 1987-1999 date class between Cwmbran, Pontypool and the A449 which may be another area to search for this threatened plant. Contains Ordnance Survey Vice-county Rare Plant data © Crown copyright Register provided by the and database right 2014. BSBI VC35 Monmouthshire Recorders February 2014. Contains data from the Tir ± Gofal Monitoring 2009- 5 Data maintained by the 2012. © Welsh km Vice-County Recorder and Government 2014. provided by the Botanical Society of the British Isles Contains Plantlife and Ireland and accessed Important Arable Plant from the BSBI Distribution Area database data 2014. Database 2014. Lesser Quaking-grass Briza minor Monmouthshire is the only location in Wales for lesser quaking-grass. Both populations lie along the A40 corridor between Abergavenny and Monmouth and were found in the most recent date class post-2000. Contains Ordnance Survey Data maintained by the data © Crown copyright and Vice-County Recorder database right 2014. and provided by the Botanical Society of the Contains data from the Tir British Isles and Ireland ± Gofal Monitoring 2009-2012. 5 and accessed from the © Welsh Government 2014. km BSBI Distribution Database 2014. Contains Plantlife Important Arable Plant Area database data 2014. Cornflower Centaurea cyanus The majority of cornflower populations in Monmouthshire are introduced from sown seed mixtures. There are three historical pre-1986 populations recorded, one population is on the coast between Newport and Cardiff, another is present on a rubbish dump in Newport but has been recorded twice in 1986 and 2006 and the other is on the Monmouthshire and Gloucestershire border along Offa's Dyke. It is unlikely that any of these records are on arable land. However, there is a very recent record of a cornflower population from a farm near Bettws Newydd that was present growing in two cereal fields. The plant was spread throughout two fields and was thought to be of natural origin germinating from the soil seed bank.