Our Flora and the Weather, 1962-63

OUR FLORA AND THE WEATHER, F. W .

1962-63

SIMPSON

THE naturalist who keeps a diary records the abundance or scarcity of animals and plants and other changes in their distribution. The factors which bring about these changes are not always understood. Wild life is quite sensitive to climatic and other variations which we do not notice ourselves and are not even recorded by the instruments of the meteorologist.

Local conditions may be ideal one season for one species and yet poor for another. The summer of 1962 was described as average when the records were sifted, yet we know that it was extremely poor for butterflies and some flowers and fruits. In fact, it was the worst " blackberry year " I have ever known.

The fruits were of very poor quality, deformed, and nearly every berry infested with grubs. However, the spring and early summer of 1962 produced the finest display of the local Herb Paris (Paris quadrifolia) I have seen for twenty-five years.

T h e winter of 1962-63 was so severe that it was certain that it would have a marked effect on a number of species. T h e air and ground temperatures for a long period were unusually low. The air temperature dropped to 7° F. in my Ipswich garden on the 23rd of January. This is the lowest reading recorded in 30 years.

On several other nights the mercury feil to 10° F., and even at 9 a.m. this air temperature persisted. The bitter gale of Saturday, 19th January, did much damage to hardy and many semi-hardy trees and shrubs. Gorse (Ulex europaeus) never recovered and nowhere in Suffolk did I observe the usual brilliant spring display.

Broom (Sarothamnus scoparius) did not suffer so badly and withstood the intense cold. The older branches of Ling (Calluna vulgaris) were badly frosted and there was but a poor display this summer at Blythburgh and Walberswick.

The cold spell came to an end in Suffolk on the 6th of March, within two days of the date I forecast in December. Snowdrops and Winter Aconites commenced to flower, and it was most unusual to see them at their best at the end of March and first week of April. The flowering of most spring and early summer plants, shrubs and trees was delayed by roughly a month, but by autumn, flowering of species was about normal. The Sea Asters (Aster tripolium) were at their best during the first fortnight of September, their usual date.

The damp spring and cold soil produced ideal conditions for a few species. Lady's Smock (Cardamine pratensis) did exceptionally well everywhere. Although a common species in Southern

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Britain, it grows andflowersto perfection in more northern areas.

The Bird Cherry (Prunus padus), so rare in Suffolk, also found the conditions ideal and the few I observed presented a beautiful sight with a profusion of spikes of fragrantflowers.Those who know this attractive species as a frequent wayside and woodland shrub or small tree in the northern counties of England and Scotland, will appreciate the conditions it requires toflowerto perfection.

Raspberries and Red Currants did very well indeed this year.

Both shrubs favour cool northern countries up to the Arctic Circle.

Düring the past twenty years the Wild Raspberry (Rubus idaeus) has been steadily increasing its distribution in Suffolk and other eastern and southern counties. This spread indicates a general change in our climate with cooler summers and colder winters.

Düring a visit to Norway in 1962 I observed that the Raspberry was abundant everywhere in the Valleys, and the Bramble (Rubus fruticosus) entirely absent. Brambles have not fruited so well in several recent years.

Bluebells (Endymion nonscriptus) were good this year and the Fritillaries (Fritillaria meleagris) at Framsden have hardly ever been better. In spite of the terrible oil pollution of the entire Suffolk coast early in the year, the Sea Pea (Lathyrus japonicus) did remarkably well this summer at Bawdsey, Hollesley, and Dunwich. However, the Yellow Vetch (Vicia lutea) made a poor display where usually fairly abundant.

We can expect to lose a number of species with a southern ränge if very cold winters continue. The frost killed many of the older tubers of the Black Bryony (Tamus communis). The small and young tubers survived fairly well. I have not observed any decrease in the number of White Bryony (Bryonia dioica).

This plant also has an underground perennial tuber, but it is in another family.

It would be of great value if others would report on losses or gains of interesting and rare plants due to the weather during the winter of 1962-1963.