Country diary: The grass is up –and so is the pollen count

Purple and silver: the solstice grass flowers. This is the first year that the whole five acres of Brogyntyn park has been left uncut, and Oswestry has designated it a wildflower meadow. The transformation is enchanting. The many buttercups, ox-eye daisies and few orchids have privilege, but the grasses are the liberated proletariat that have never realised its full potential before.

Common grass names have an earthy poetry: fescue, false oat, foxtail, fog, bent, brome, couch, cocks foot, timothy, rye, sweet vernal, squitch. For a couple of days it stops raining and warms up a bit. When the sun comes out, so does the pollen. VH, a red sign on the weather map, announces a very high pollen count (more than 150 grains per cubic metre of air). About half of the people in the UK report hayfever symptoms – allergic rhinitis. It can mean itchy eyes, runny noses, sore throats and sneezes for millions, but for some the reaction can be deadly serious. Dogs, cats and horses are also affected, as if sacrificing an immune system is a trade-off for domestication.

Climate change has altered flowering times and extended the pollination period, increasing human exposure to allergen loads in pollen; this is predicted to intensify. Pollen is an important link between the biosphere and the atmosphere. This wind-drift of ghostly dust contains granules that look like microscopic sci-fi sculptures, each holding two male gametes to fertilise an ovule. Only a fraction will do this and many will end up food for palynivores (pollen eaters) – some spiderlings and hoverflies eat pollen. When herbivores such as cattle, horses or rabbits consume it, their dung feeds beetles and springtails in the soil; ants stash pollen underground to become nutrients for networks of fungal mycelium.

Because of a decline in herbivores – here at Brogyntyn, for example, dog poo in the grass prevents grazing – the massive global surplus enters the atmosphere, leading to an epidemic of hay fever. Pollen in peat deposits is a historical climate archive and at crime scenes it is forensic evidence. Following a meadow brown butterfly, whose caterpillar feeds on these grasses, how much pollen is deposited in me? All this pastoral summer solstice beauty, it’s not to be sneezed at.

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