Caterpillars Attack Crops In Northland

Northern Advocate, 9 April 1947, Page 2

Caterpillars Attack Crops In Northland

DROVES of caterpillars have made their appearance in several Northland districts where they have inflicted severe damage on pastures and crops.

At Ruakaka the pests have completely stripped a fine maize crop and similar reports have been received from other areas.

Early in May of last year the caterpillars were particularly numerous. They caused considerable damage in die Whangarei and Waimate North areas and were prevalent in millions. Other districts*-were not affected to die same extent. So far this season they have not been present in such great numbers, out there is a distinct danger of their depredations becoming more serious as the season advances towards winter.

The caterpillars are of the army worm, or cut worm, variety. In colour they are a dirty green and they grow to about an inch in length. Last year some of them were identified by Mr W. A.. Given, of Whangarei. as being the larva of the kowhai moth.

They generally make their appearance in springtime, later broods attacking the foliage cf crops and newly planted pasture. Their numbers seem to increase after heavy rain, when they become most noticeable. HARROWING BEST

Being general feeders, they attack anything green and succulent. Maize crops usually suffer.

Poisoned baits and sprays of arsenical compound can be used against them with some measure of success, but such measures cannot be applied to pastures, owing to the danger to cattle.

Crops can be treated in this manner, during spring time or early summer.

No practical steps can be taken against the pest during autumn months, when the ground is usually jloo heavy to use rollers. In any case, rollers are not entirely efficacious, even under good conditions. The only course at this time of the year seems to be the use of harrows, which would expose large numbers of caterpillars to their natural enemies, the birds.

Large flocks of starlings can be attracted in this manner, and in rough weather, when seagulls come inland, they also can assist in reducing the numbers cf the caterpillars.