The Woodland Trust, the UK’s leading woodland conservation charity has highlighted evidence that spring flowering is lagging behind by several weeks this year, as seen in parks gardens and woodland across the UK.

It is normally hard to predict until the season is well underway whether spring is late or early for that year, but the lack of sightings so far for many spring species is striking.

Dr Kate Lewthwaite of the Woodland Trust said: “The Trust holds records going back to the 1600s which show us year on year timings of spring events. From this we can see how the changing climate is affecting our plants and wildlife, showing us this year that spring is about a month behind.”

Some examples of this late spring activity for spring 2010 are:

Flowering dates in blackthorn: normally our average UK flowering date is mid-March, and the Trust would expect around 1,000 sightings by now but it has received just one single record so far this season.

Flowering in celandine: again strikingly few for the time of year. In most years The Trust would have flowering records right across the UK by this point. This year there is sparse coverage in the south and midlands and almost none reported in Northern England and Scotland to date.

Coltsfoot: the Trust would have expected several 100 observations by now, the average UK date being mid-March; so far it has received just 10 records.

Hawthorn budburst: the Trust would have expected over 1,000 sightings by now, as mid-March is a typical average date for UK sightings; only 14 records have been received.

This has been an exceptional season; December 2009 was the coldest for 15 years, January 2010 the coldest for 13 years and February the coldest for 19 years.

However, despite this year’s late spring, the season is actually arriving in the UK on average earlier than it did 30 years ago. But how are our species responding? This is where the Woodland Trust is looking for the public’s help.

“Simply by letting us know when and where you spotted your first snowdrop or frogspawn of the year, we can begin to understand the impact of climate change on our native species,” confirmed Dr Kate Lewthwaite, the Trust’s Nature’s Calendar manager.

The Trust is keen for more volunteers to get involved so staff can understand what’s happening this year.

The data provided by Nature’s Calendar recorders is used in real science, and recently was included in a high profile report led by Dr Stephen Thackeray and Professor Sarah Wanless of the Centre for Ecology & Hydrology.

The study considers a diverse array of organisms including plankton, plants, insects, amphibians, fish, birds and mammals. On average, the seasonal timing of reproduction and population growth has become earlier by more than 11 days over the whole period, but change has accelerated in recent decades.

To learn more, or to take part please visit www.naturescalendar.org.uk