Plague Of Army Worms Invading Farms In North

Press, Volume XCV, Issue 28268, 4 May 1957, Page 10

Plague Of Army Worms Invading Farms In North

(New Zealand Press Association) WELLINGTON, May 3. Millions of army worms are on the march in many parts of the North Island, devastating pastures on hill country and on first-class fattening farms in rich flats. Infestations are reported from the Wairarapa, Northland, South Auckland, Hawke’s Bay and Wairoa and the Department of Agriculture is investigating reports that the invading caterpillars are immunt to many of the better-known and more widely-used insecticides.

In the Wairarapa, each day has brought fresh reports of infestations in new areas which extend along the east coast from Martinborough to Castlepoint, in hill country. The latest reports show that hill country within five miles of Masterton also is heavily infested.

Aerial attacks on the invaders in the Wairarapa began this morning on Pahaoa Station, Hinakura. when an aircraft fitted with special tanks flew many sorties to spray the heavily infested hill country on the station. In Northland, there is heavy infestation in the Mangonui county and on its southern borders and pastures are being devastated from Umawera in the south to Waiharara on the far northern peninsula. The instructor in agriculture at Whangarei (Mr H. G. Halliwell) said today that hundreds of acres are affected and that pastures are often a complete “write-off.” Caterpillars in some places were so numerous that even rushes had been stripped. Immunity to Insecticides A Department of Agriculture entomologist has been studying the problem of the army worm on the east coast of the island, and he will soon go to the Manukau district in South Auckland to investigate the apparent non-effect of insecticides such as D.D.T. and dieldrin on the worms. A spokesman for the Extension Division of the Department of Agriculture said today that the results of the entomologist’s work would be used in trying to find an effective defence against the worms.

No estimate of the area affected by the worms is available, as reports of some outbreaks in the east coast of the North Island have only just reached the department. but messages received from the Waiuku district (South Auckland), Wairoa, Hawke’s Bay, and Manukau indicate that the area may be substantial and the problem serious.

In an outbreak in Wairoa last year, dieldrin was effective, but in some instances D.D.T. was better- . X A mixture of superphosphate and D.D.T., successful in destroying outbreaks in Wairoa and Canterbury last year, was tried at Pukekohe recently, but although many caterpillars were killed, many thousands survived. An alternative to spraying the worms is to lay a bait made up of oatmeal and sugar, and an insecticide. The worms act in a similar way to a swarm of locusts, travelling across country on a narrow front and eating everything in their path. They used to be more prevalent m flooded areas after the flood had dropped, but in the last two or three years they have appeared m the hill country of the North Island. They are associated with warm, wet conditions after a dry spell.