Seasonal anomalies are blooming strange

IT’S been a funny old year.

A long and cold winter transformed into a warm, calm and sunny April. Now, in May, we seem to be getting April weather — showery, blustery and rather cool.

That long period of warm weather in April seems to have speeded up many seasonal changes associated with spring. Trees, shrubs and wild flowers in the countryside around me have bloomed a week to ten days earlier than usual this year.

I think that one of our most spectacular wild flowers is the yellow-flag iris that blooms in wet places along river and canal banks and the shores of ponds and lakes. I expect the first flowers to open in late May and early June. But they have been in flower for at least a fortnight along the banks of the canal.

A few weeks ago, along the same canal banks, I noticed something rather strange. The primroses and the cowslips were in bloom at the same time. Usually, primroses are well gone before the first cowslip breaks bud. But, this year, cold weather in February and March seems to have delayed the primroses and very warm weather in April seems to have encouraged the cowslips to blossom early.

They are closely related — in fact, this year I found a couple of hybrids between the two. But the primrose is originally a plant of deciduous woodland and the cowslip a meadow flower. So the primrose has evolved to flower early in the year, before the tree canopy closes over.

The taller cowslip doesn’t face the same sort of competition, and gets the benefit of even more life-giving light by hanging on until the days are longer.

Blackthorn is also an early-flowering tree or shrub but it was late this year. Hawthorn was early. For once, it looks as though the May blossom will coincide with the calendar month.

Consistent, day-time temperatures of up to 20 degrees in April seem to have affected the insect world, as well. Red admiral butterflies are one of our most spectacular species, but I associate them mainly with late summer and early autumn. But, at the beginning of the month, in two quite separate places, I spotted one on the wing.

But the most reliable observers when it comes to the timing of seasonal events are fly fishermen. I’ve had several reports from fishing friends, from different parts of the country, saying that hatches of mayfly and of sedges are both heavy and early this year.

Unfortunately, I haven’t had the time to dust off my fly rod and check out these reports for myself. But I have done some canal travelling in my boat and I’ve been amazed at the amount of large flies I’ve seen, including examples of the great red sedge, commonly known to Irish anglers as the murragh. This is a fly that fishermen associate with warm evenings in June, not with early May.

Sedge flies are known to American anglers as caddis flies and to scientists as Trichoptera. The American name is a good one, because these insects spend most of their lives under water as caddis larvae. Many species build houses to live in during their larval existence. Typically, they are tube-shaped and glued together out of grit or pieces of plant material.

When they hatch out as winged adults, they look very like moths and fold their wings over their bodies in a similar manner. There is one difference that makes it easy to tell a sedge from a moth — though you may need a hand lens. All moths have scales on their wings and all sedges have hairy wings.

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