Exotic species used to seed Yorkshire motorway
Reported in BSBI News September 2000 by John Taylor
A new stretch of motorway was constructed lining the M1 at Lofthouse with the A1 at Aberford in West Yorkshire. The seed mixture used in landscaping roadside verges proved most interesting during 1999.
Large numbers of Sanguisorba minor ssp murictata (Fodder Burnet),Trifolium hybridum (Alsike Clover), Onobrychis viciifolia (Sainfoin) and Cichorium intybus (Chicory) were evident throughout the year. These cultivated fodder plants would have grown vigourously unchecked.
The colourful annuals Centurea cyanus (Cornflower), Tropaeolum majus (Nasturtium) and Calendula officinalis (Pot Marigold) were also present in numbers. The cornflower is an inappropriate annual as it requires regular managment, as found in traditional hay meadows. Nasturtium and Pot marigolds are obviously garden flowers and are certainly not suitable for countryside planting.
Daucus carota (Wild Carrot) and Erodium cicutarium (Common Stork's-bill) also occurred and possibly came in with aggregates and other construction materials.
Perhaps the most interesting element in the mix was representatives of the knapweed genus. Both Centurea nigra (Common Knapweed) and C. scabiosa (Greater Knapweed) were often seen, and as such represented some of the few species that were suitable to be planted here. However, Centurea rhenana (Panicled Knapweed) was identified against herbarium material and proved to be the first British record since c.1930.
On 17th October 1999, 162 specimens were counted on the verges of a new stretch of service road. Details of various seed mixes were supplied by the landscaping contractors, stating that as much seed as possible would have been obtained in the UK, with the balance of the requirement obtained from European sources.