When we were out on the walk when I noticed the first bluebells of 2012, I also noticed that the hawthorn blossom, or “may” as it’s also known, was out. This seemed remarkably early this year too, but on reflection I realised I was wrong. Here’s why…
After our walk, it occurred to me that the hedge where I spotted the flowers had no leaves and normally hawthorn leaves arrive before the blossom, so it was probably something else I’d seen. A short burst of Googling later and I’d identified Blackthorn (Prunus spinosa) as a likely contender. Last weekend I went back to the place where I saw this blossom (the public footpath at NZ306414) to confirm it and to capture photos of the details of the two plants.
As you can see from the photo above, the Blackthorn flowers are past their peak already, with the petals starting to discolour around the edges or already fallen in a lot of cases. This particular hedge is exposed and south-facing, so it’s likely that a more sheltered plant could still have more blooms. At the point I saw this two weeks previously, the leaves didn’t even register with me so must have been at the bud stage.
Compare the Blackthorn to the progress of the Hawthorn (Crataegus monogyna) above. The leaves are mostly well developed but the flowers are still tightly packed in clusters of spherical bud casings.
The blossom of the two shrubs looks very similar, so it’s very easy to understand the confusion; each belongs to a different genus but are part of same family (Rosacae). There are other differences but in my opinion, the leaves are the easiest route to identification.
- Timing: Blackthorn blossoms in early spring, shortly before the leaves (normally March in Durham). Hawthorn flowers after the leaves emerge, normally in May.
- Shape: the leaf shape is very different. Blackthorn is oval with a slight serration to the edge, while Hawthorn is broader and deeply lobed. Examples of both are visible in the photos above.
The photos here were taken using a 100mm macro lens to pick out the details. Light drizzle and heavy cloud gave less than ideal lighting conditions; there were no harsh shadows, but this gave long shutter speeds when stopped down at lower ISOs. I used a tripod but there was a slight breeze which was enough to result in motion blur, so I chose to compromise on the depth of field with a wider aperture.
So if you see a hedge covered in white blossom but no leaves in March or early April, there’s a good chance it’s Blackthorn, not Hawthorn. Spring may be early this year, but it isn’t quite that early!