Species Spotlight Challenge - Day 3 - Yorkshire Fog

On a sunny day in Yorkshire I was able to get some nice pictures of one of our commonest grasses - 

Yorkshire-fog (Holcus lanatus).

I suspect that a lot of people think that there is one thing called 'grass' but actually in the British Isles alone there are over 200 species of grasses, in 67 genera, that have been found growing in a wild state (i.e. not just in a garden or a botanical collection). In the whole world it is about 12,000 species in 771 genera, including nearly all of the grains we eat and some things you might not expect to be grasses such as giant bamboos which can grow to 30 metres tall (98 feet) in height and 30cm (12 inches) in diameter.

This one, however, is probably the grass that most people in the UK and Ireland are familiar with. Its soft downy grey-green leaves and purple tinged flower heads can be seen almost everywhere in these islands (except possibly in some very mountainous parts of Scotland), and is common in gardens, waste-ground, meadows and woodland clearings. It doesn't always look the same though, as these photos, all taken today in North Yorkshire, show. The purple tinge is most likely to be seen when the flower heads have just appeared (as in the first photo). When they have opened out more they could be mistaken for a different species, looking much more grey-green - this is shown best in the second picture. When the flowers have dried up and gone to seed they look different again - a pale straw colour.

The greyness comes from the short downy hairs that the plant is covered with. This distinguishes it from its close relative, Creeping Soft-grass (Holcus mollis), which is mostly hairless except for the long hairs on the 'nodes' (the knee-like joints in the stems), giving rise to the amusing (slightly) saying among botanists - 'Molly has hairy knees' (honestly we hardly stop laughing on botanical field trips 😂). It also gives rise to the second part of the scientific name - lanatus means 'woolly' in Latin.

Another distinguishing feature of Yorkshire-fog is the pink veins at the base of the stems, sometimes called 'stripy pyjamas'.

Although it is sometimes considered a weed by farmers and gardeners, a field full of Holcus lanatus can be a beautiful sight on a windy day. It is also an important foodplant for the caterpillars of the Small Skipper butterfly (Thymelicus sylvestris).