MILLIONS OF PARASITES

Nelson Evening Mail, Volume LXX, 7 October 1936, Page 9

MILLIONS OF PARASITES

” THE BATTLE WITH PESTS SAVING THE EMPIRE’S CROPS . WORK AT FARNHAM HOUSE From a tall, white country house in the Buckinghamshire village of Farm ham Royal, millions of insects are .being sent to all parts of the British Empire, there to do battle with pests .which ravage crops and destroy livestock. says (he "Evening Standard.” Farnham House Laboratory, in association with the Imperial Institute of Entomology, was opened in 1926 under a scheme drawn up by the Empire Marketing Board. Its funds are derived from grants made by various Dominion Governments. It is now under the control of the Imperial Agricultural Bureau. ? The research staff of the laboratory are engaged in discovering and developing parasites which prey upon pests injurious tq Empire crops. The trite rhyme about "big fleas with fleas'.'noon their, backs to bite ’em” is one the staff are tired of hear- , mg. but it does pithily summarise the j scope of the work.

TWO RECENT CONSIGNMENTS Recently 4.000.000 parasitised co- j coons of the spruce sawfly set out in containers to Canada. On ar- I rival t’-my will set, about, the task of i exterminating pests which are decimating whole forests of white spruce, I the basis of paper pulp.

Another quarter of a million cocoons of the ragwort seedfly have set sail for New Zealand to devour the ragwort weed. These two most recent consignments bring the total of insects despatched from Farnham House Laboratory during the ten years of its existence to 32,332,536, of which 21,267,133 have been sent out within the last six months.

These figures give some indication of the rapid growth of the work. The insects have been despatched to Canada. South Africa, Australia, New Zealand. India, Kenya, the West Indies. Cyprus, the Falkland Islands and Ceylon, as well as parts of Great Britain and Ireland. The cold storage equipment of modern steamships makes it possible for insect pests to travel many thousands

of miles from one country to another unaccompanied by the parasites which batten upon them in their old haunts, and so preserve the "bug balance.” Set free in pastures new they increase and multiply with amazing rapidity. NATURE ALONE EFFECTIVE Of the 183 worst insect pests in North America almost half have been introduced from foreign countries, and a large proportion from Europe. The Hessian fly each year destroys about £BOO,OOO worth of wheat. The gipsy moth, accidentally introduced into America about 60 years ago, costs the United States £50,000 a year. The sum of £2,000,000 was spent in one year in fighting the European corn-borer.

Once firmly established, it is almost impossible to stamp out a pest by such methods as spraying and fumigation. The only way is to introduce the parasite control, and it is for this purpose that the Farnham House Laboratory exists. Here are a few examples:— Cabbage butterflies accidentally shipped to New Zealand with a cargo spread so rapidly that cabbage growing became uneconomic in the North Island. The stricken farmers sent an S.O.S. to Farnham House. The staff responded promptly with swarms of chalcid wasps and in twelve months 90 out of every 100 cabbage butterflies on the island had been destroyed. Cattle and horses in New Zealand suffer much from the ravages of the ragwort weed, which is poisonous, and the laboratory has just sent out 250,000, cocoons of the ragwort seed fly to combat this evil.

A hundred men and women were set at work in Norfolk, where ragwort flourishes, cutting off the tops of the weeds, with the parasites adhering !o them.

Each evening they were sent by express train to Liverpool street Station, London, where they were collected by lorry and taken to Farnham Royal. There the cocoons were shaken out, and placed in the refrigerator, which retards development by its approxim-. ation to wintry conditions. While still in the hibernation phase, the cocoons were packed and transferred to the cold storage chamber of a ship for New Zealand. On arrival the insects will emerge from their cocoons under favourable conditions, and be launched on their crusade against the ragwort.