From the Woodland Trust website

Even the cold snaps can't put a stop to Mother Nature's early schedule. April is the new May, as this year's bizarre weather continues to bring sightings of species normally flowering in May like hawthorn and the oxeye daisy – both ahead of their traditional flowering dates – and swallows and swifts returning ahead of schedule.

To humans it seems like a cold start to the year, but the monthly temperatures have actually been slightly above the average.

The maytree, mayblossom and mayflower are all common vernacular names for the hawthorn, one of the best loved native British plants, but do those names need a re–think?

Research by the Woodland Trust going back decades points to changes in the plant's timings over the past 30 years, suggesting these days it could be more appropriate to call it an 'april tree', april blossom or april flower.

Folklore says Hawthorn, common in hedges, scrub and woodland, is always late, rarely ever in flower by the first week of May, and such was the wait that villagers would linger on stories of early flowering bushes in order to rush for the first blossom of the year. Workers would also pick the leaves on their way to work to supplement their sandwiches, referring to it as bread and cheese.

Research from Nature's Calendar, the world's leading study into the timings of nature, also known as phenology, shows, however, that averages for the last 10 years have been in the middle of April, and this year confirms that trend with early sightings being recorded.

Climate change is affecting the timing of plants and wildlife, and over the past 30 years there has been a marked advancement of spring flowering species in line with annual temperatures.

An excellent example of this is hawthorn, which holds the clue to its historic flowering time in its many vernacular names. Commonly not seen until early May, over the past 30 years it has been edging its way into April.

Culturally and historically it is seen as signifying the start of summer, but thanks to the exceptionally mild start to the year we are experiencing, this summer signal is arriving weeks earlier than the 11 May average.

Hawthorn is surrounded by folklore and research is being carried out on its possible health benefits, including lowering blood pressure for heart related diseases and as a sedative. The blossom of hawthorn is also made into tea which is claimed to help the heart, circulation and cholesterol.

If you'd like to get involved with Nature's Calendar and provide data for real science, you can register at www.naturescalendar.org.uk and record your sightings.