Denbighshire The underlying geology and soils of Denbighshire creates a great variety of land uses with arable land historically being concentrated in the lowlands along the boundary with Caernarvonshire, along the coastal strip and surrounding the major towns and cities. 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 th fertilisers in the mid 20 Century has led to an increase in crop production in some areas as weed control has improved. However, there is an estimated 68% contraction of cultivated land and land under short-term rotation between the 1930s and 1990s. Arable cultivation is still continued around Abergele, Denbigh, Ruthin, between Chirk and Wrexham and north-east of Wrexham. The decline in arable cultivation could be due to a number of reasons including the general change in farming businesses towards more livestock farming and pastoral land; the increase in herbicides and fertiliser costs which may lie beyond the means of small-scale farms; and the volatility of cereal prices may also have led to a decline in arable cropping with high yields only breaking even in some years. There is a substantial concentration of arable land in the 1990s survey with larger blocks of cultivation being undertaken. This may be the result of agricultural intensification and a greater use of herbicides and fertilisers. Denbighshire is a rich vice-county with records of 19 out of 30 threatened plants. Some of the records of the threatened arable plants are historical with species such as red hemp-nettle Galeopsis angustifolia, Henbane Hyoscyamus niger, corn buttercup Ranunculus arvensis and shepherd’s-needle Scandix th pecten-veneris not being found since the early 20 Century. There are more recent records of other threatened plants such as annual knawel Scleranthus annuus, small-flowered catchfly Silene gallica and narrow-fruited cornsalad Valerianella dentata, but they are still relatively historical recorded in the 1987-1999 date period. Prickly poppy Papaver argemone has been recorded in Denbighshire but has only been found on sand dune habitat. Other plants such as corn chamomile Anthemis arvensis have been introduced through sown seed. Some populations of cornflower Centaurea cyanus and corn marigold Glebionis segetum are also introduced whilst others are considered natural. There are also populations of large-flowered hemp-nettle Galeopsis speciosa recorded recently from farmland in Denbighshire. The only population of mousetail Myosurus minimus recorded in any of the vice-counties examined for arable plants is located on the Denbighshire boundary with Cheshire. The distribution of corn mint Mentha arvensis is an oddity as it has generally been recorded at too small a scale to provide an accurate fix on location. This means that it appears to be relatively sparsely distributed across Denbighshire whereas it may actually be more widespread. However, the small scale of the records, generally hectads (10x10km squares), may hide a population decline and further investigation of the population dynamics of this species is required across Wales. Two arable plants corn spurrey Spergula arvensis and field woundwort Stachys arvensis are also noted as widespread in the hectad records, but there are few records at a refined scale making the populations in Denbighshire look sparse. Six tetrads (2x2km squares) have three or more threatened arable plants and should be targeted for suitable management practices. Denbighshire has a number of locations that would qualify for Important Arable Plant Area status as they have good assemblages of arable plants. These are found along the boundary with Caernarvonshire. There are two tetrads considered to be of National Importance and two considered to be of County Importance for arable plants. These locations should be targeted for arable plant conservation along with threatened plant populations to maintain the diversity of these flowering species across the vice-county. Very few areas of Denbighshire have been rigorously surveyed for arable plants and in general there is under-surveying of this type of habitat. Further surveys of the remaining arable land along the coastal strip and the blocks of arable land elsewhere in Denbighshire may identify new populations of arable plants. Specific surveys targeted at the locations with historical records, particularly large-flowered hemp-nettle and mousetail, should be undertaken as these plants are very scarce elsewhere in Wales. Denbighshire 1933-1949 Arable Land Use Arable land in the 1933-49 period was extensive across Denbighshire covering 19872 ha. In total, 477 tetrads out of 577 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 foothills of Snowdonia National Park and moorland or the Cambrian Mountains around Moel Seisiog and Moel Llyn, Mynydd Hiraethog and Clocaenog Forest, and moorland at Berwyn, Cyrn-y-Brain. There is one further gap in arable land to the east of Bangor-on-Dee. Concentrations of arable land are present around Llanrwst, Ruthin, Llanelidan, between Llangollen and Chirk and north-east of Wrexham. Contains Ordnance © Cyfoeth Naturiol Survey data © Crown Cymru, 2014. © Natural copyright and database Resources Wales, 2014. right 2013. ± 5 km Denbighshire 1979-1991 Arable Land Use Between the 1933-49 land use survey and 1979-1991 Phase 1 habitat survey of Wales there was a 68% contraction in arable land use across Denbighshire. 6311 ha of arable land was identified in the Phase 1 habitat survey with cultivated parcels of land falling in 347 out of 577 tetrads. Arable land has particularly contracted in the Cambrian Mountains, principally around Llandwst and the coastal corridor. Concentrations of arable land are still present in Denbighshire including east of Abergele, Denbigh, Ruthin, between Chirk and Wrexham and north-east of Wrexham. There has been a local increase in arable land use around Bettisfield, Bronington, Horseman's Green and Egwlys Cross at the eastern end of Denbighshire since the 1930s. © Cyfoeth Naturiol Cymru, Contains Ordnance 2014. © Natural Resources Survey data © Crown Wales, 2014. copyright and database right 2013 ± 5 km Denbighshire Soil Map The most common soils in Denbighshire fall within the clay category and is the dominate substrate for 463 tetrads out of 577 tetrads. Clays vary between neutral to calcareous, with more alkaline soils on the ridge. Lime-rich soils are present on a ridge where the soil is thin and the alkaline nature of the bedrock dominates the substrate material. Lime soils are considered dominant across 20 tetrads. Sandy soils are the dominant soil type for 34 tetrads, particularly around Wrexham and north of Ruthin. The other soil category is the dominant substrate for 60 tetrads. This includes deep peat-rich that are present in upland areas and disturbed soils from old mining activity. Contains Ordnance © Cyfoeth Naturiol Survey data © Crown Cymru, 2014. © Natural copyright and database Resources Wales, 2014. right 2014. ± 5 km Corn Chamomile Anthemis arvensis There are two records of corn chamomile in Denbighshire. The first population near Llansannan was recorded once in 1995 and is believed to come from sown seed as part of a wildflower mix. The other record near Pentredwr falls in the recent post-2000 date class and is believed to originate from introduced seed as it is alongside a road. Contains Ordnance Vice-county Rare Plant Survey data © Crown Register provided by the copyright and database BSBI VC50 Denbighshire right 2013. Recorder February 2014. ± Data maintained by the 5 Vice-County Recorder and km provided by the Botanical Society of the British Isles and Ireland and accessed from the BSBI Distribution Database 2014. Cornflower Centaurea cyanus There are five records for cornflower in Denbighshire, four of which are considered to originate from sown seed mixtures and one is naturally occurring from the soil seed bank. Three of the introduced populations of cornflower are alongside roads and result from re-seeding along these transport routes or floral displays. The fourth is close to the Llangollen Canal and the presence of other plants often sown in annual flower mixtures, such as corn marigold, make the origin of this plant suspicious and more likely to be from an introduced source. The naturally occurring record near Llangollen dates from 1861 and has not been found since. There are records of arable land use located within this area from 1930 but none in the 1990 land use map. Contains Ordnance Vice-county Rare Plant Survey data © Crown Register provided by the copyright and database BSBI VC50 Denbighshire right 2013. Recorder February 2014. ± Data maintained by the 5 km Vice-County Recorder and provided by the Botanical Society of the British Isles and Ireland and accessed from the BSBI Distribution Database 2014. Red Hemp-nettle Galeopsis angustifolia There are two records of red hemp-nettle in Denbighshire. Both fall into the historical pre- 1986 date category and were recorded before 1800. The record near Llangollen is located on limestone along a canal bank whilst the record near Llansilin is close to a record of arable land use from the 1930s. Both records are thought to be of natural origin from the soil seed bank. Contains Ordnance Vice-county Rare Plant Survey data © Crown Register provided by the copyright and database BSBI VC50 Denbighshire right 2013. Recorder February 2014. ± Data maintained by the 5 Vice-County Recorder and km provided by the Botanical Society of the British Isles and Ireland and accessed from the BSBI Distribution Database 2014.