With many trees showing full green coats, its becoming more difficult to remember the intense cold of last winter. Yet the scars can still be seen, be it gaping potholes in the tarmac of roads or the desolation of the Cordyline trees in many gardens (1). Worries of a lack of salt for the roads seem a little quaint now, as the warm days bring forth multitudes of insects. However as flowers seem to pop up overnight, the prospect of future cold winters may indirectly influence their future populations. Over 100,000 tonnes of salt were used on Irish roads during the 2010-'11 winter (2), making verges more suitable for plants usually associated with coastal habitats, plants better able to cope with high saline conditions. This is common throughout America and Europe and was first noted in 1982 in England (3), with the coastal plant common scurvy grass (Cochlearia offininalis) being added to a list of roadside plants for the first time.
|Common Scurvy Grass, Cochlearia officinalis|
C. officinalis should actually be seen as a species complex rather than a distinct, single species, with a number of different cytotypes present, each with a number of ecological distributions (4, 5). Interestingly, C. officinalis originated as a derivative of C. pyrenaica, and the origins of many Cochlearia spp. are as a result of changes in ploidy levels (6), demonstrating the role that polyploidisation plays in the evolution of new species.
- Scott and Davison, 1982. Watsonia 14 pp. 41-52
- Erikson and Nordal, 1989. Ecography 12 pp. 31-38
- Pegtel, 1999. Plant Species Biology 14 pp. 201-215
- Koch et al., 1998. Botanica Acta 111 pp. 411-425