Tuesday, February 28, 2012

Taking Advantage of Us

Rue-leaved Saxifrage, Saxifraga tridactylites
One of the smallest saxifrages present in Ireland, the Rue-leaved Saxifrage (Saxifraga tridactylites), is commonly found on dry grasslands or hedgebanks. It is noticeable at this time of the year as it is coming into flower, producing small, white blossoms forming on stems arising from the finger like leaves (hence the name tridactylites name, literally "three fingered"). There are more than one flowering stem per plant, in contrast to some of the other saxifrages which have just one stem per plant (1). In the past c. 50 years, it has shown a marked increase in its range across Europe, an increase associated with its colonisation of man-made habitats such as limestone walls, spaces in footpaths and in particular railway constructions (2). Such expansion is in marked contrast to many other plant species that are declining in numbers due to habitat destruction and fragmentation and the intensification of land use practices. S. tridactylites will continue to flower from now till May-June, when the annual plants will set seed and die off.

Rue-leaved Saxifrage, Saxifraga tridactylites

  1. Phillips, 1977. Wildflowers of Britain p. 30
  2. Reisch, 2007. Conservation Genetics 8 pp. 893-902

Monday, February 20, 2012

Return of the Frog

Frog Spawn
Last March, this blog reported a batch of developing Common Frog tadpoles (Rana temporaria) that had succumbed to the intense cold of winter 2010-11. A combination of low rain fall and harsh frosts had left a large mass of c. 7 day old tadpoles stranded and frozen some distance from a marshy pool in which they were no doubt laid but which had since retreated. This year, re-examination of the site showed a new batch of eggs. This time they are well within the confines of the marsh pool - hopefully some of them will develop into adults.
Frog Spawn

Wednesday, February 1, 2012

Early Flowering Plants

Usually flowering in June, the mild weather has lead the Common Knapweed, Centaurea nigra, to flowering at the start of February
A recent comment on my "Guillemots and the Climate Change Mistake" post by Tony Powell led me to his wonderful naturestimeline blog. It is concerned with documenting phenological (the timing of life-history) events in the UK among other things, and inspired me to examine any such events happening in Cork, Ireland.

Meadow Buttercup, Rannunculus acris
Due to the mildness of the winter, I examined a public walkway along the estuary of the river Lee for signs plants in flower. It revealed eight plants in flower on this, the first of February (listed below).

Plant Name Common Name Flowering Date
2012 Average*
Anthriscus sylvestris Cow Parsley 1st Feb April
Centaurea nigra Common Knapweed 1st Feb June
Medicago lupulina Black Medick 1st Feb April
Rannunculus acris Meadow Buttercup 1st Feb April
Senecio jacobaea Ragwort 1st Feb June
Trifolium pratense Red Clover 1st Feb May
Ulex europaeus Common Gorse 1st Feb February
Vicia sepium Bush Vetch 1st Feb April

Of these, only Common Gorse (Ulex europaeus) has an average flowering date usually near this time. The expected flowering dates for the others ranges from April to June. In addition, four more plants were seen to be in bud and on the verge of flowering: Ribwort Plantain (Plantago lanceolata), Common St. John's Wort (Hypericum perforatum), Cowslip (Primula veris) and Spear Thistle (Cirsium vulgare).

Bush Vetch, Vicia sepium

*Average flowering dates from Sterry, 2004, Collins Complete Guide to Irish Wildlife