Coltsfoot - a little ray of sunshine in the spring
Judith Garforth, 24/02/2020
Coltsfoot flowers are a little ray of sunshine in the spring! But they are appearing later than we’d expect. If you spot a coltsfoot plant flowering this year, please add a record to the Nature’s Calendar database to help scientists investigate how weather and climate are affecting their flowering time.
What does coltsfoot look like?
Coltsfoot (Tussilago farfara) are dandelion-like plants with bright yellow flower heads which appear, one per scaly stem, before the leaves emerge. They are a member of the daisy family and the flower head is actually a collection of florets (tiny flowers). They usually flower from February to April and are often found on arable, bare and waste ground (especially on clay soils) and along roadsides. Don’t confuse them with dandelions which can flower at the same time but have smooth stems and toothed leaves.
How to add a record to Nature’s Calendar
First find a coltsfoot plant that you can keep an eye on this spring. When the first flower head starts to open up (when you can see inside it) make a note of the date and add a record of coltsfoot ‘first flowering’ on our website. You can upload a photo too. Your record will go instantly into the Nature’s Calendar database to be used by scientists for research. You can view your record on the map and see where and when coltsfoot flowers have been spotted across the UK so far this spring.
Is coltsfoot flowering getting earlier or later?
First flowering of coltsfoot was chosen as a recording event for Nature’s Calendar because it was also included in the phenology recording scheme run by the Royal Meteorological Society (RMS) between 1875-1947. By comparing data from Nature’s Calendar (which started in 1999) to the historic RMS data, scientists can investigate how coltsfoot flowering times have changed over time and whether climate and weather trends are having an effect.
Coltsfoot is thought to flower earlier during warmer springs and so we would also expect flowering times to have got earlier over time as the UK climate has got warmer. However, some studies have shown that coltsfoot flowering time has actually got later. It’s a bit of a conundrum!
One explanation is that the abundance of the flower could have decreased. When coltsfoot was chosen for the RMS scheme, it was selected because it was an obvious and widespread early spring flower. It still has a good UK spread and is recorded all over the UK, but if it’s less common now it’s possible recorders simply don’t have as many opportunities to spot the flowers, leading to later records. A second explanation is that autumn temperatures may also have an affect on coltsfoot spring flowering time (warmer autumns resulting in later spring flowering). More investigation is needed…
We’d really like the help of #wildflowerhour participants to add coltsfoot first flowering records to the Nature’s Calendar database this year! If you notice coltsfoot plants growing during your weekly flower hunts keep an eye on them and let us know when they first start to flower. Add your flowering dates to the Nature’s Calendar database and share your photos during #wildflowerhour (8pm-9pm every Sunday on twitter). Don’t forget to include the hashtags #wildflowerhour and #coltsfootchallenge·