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ARMYWORM The native armyworm was present in increased numbers in oat and wheat crops. This insect also does serious damage to seed crops of rye-grass, and the development of a satisfactory control is highly desirable. Reasonably good control was obtained this year with a gammexane-bran bait, but further work is required. PHORMIUM FLAX INSECTS An officer is stationed at Foxton as one of a team investigating the causes of " yellow-leaf " disease in flax. A survey of the insects associated with flax has been followed by experiments with field-collected material of three insects that could be vectors of a virus, though it is not yet proved that the disease is caused by a virus. A survey has also been made of flax insects in North Auckland. GREEN-VEGETABLE BUG This insect is spreading and becoming increasingly destructive. A survey made this year showed that the parasite introduced from Australia last year is established in at least one locality in North Auckland. It is highly desirable that at least one other parasite of this pest should be introduced. TOBACCO-LEAF MINER This insect, also known as potato tuber moth, caused severe damage to tobacco in the rosette stage. This was checked by DDT dusting. The lifehistory and ecology of the insect in the field are under investigation. A parasite obtained from Australia has been liberated in the affected area. HORNTAIL BORER IN PINES The annual distribution of the parasite already established in New Zealand has been continued. An officer of the Station is to serve on the committee recently set up to consider the role of the borer in pine forests and methods for its control. STORED-PRODUCTS INSECTS The accumulation of material and information relative to existing storedproducts insects in New Zealand has been continued. A paper dealing with the identification and economic importance of the Australian carpet beetle, not previously reported from New Zealand, has been submitted for publication. WEED CONTROL A recent survey shows that the ragwort-seed fly is established in the Putaruru area. The distribution of the St. John's Wort beetle has been continued. This year material was sent to several localities in the North Island. MISCELLANEOUS A study of the tick fauna of the New Zealand region has been made and is being prepared for publication. A preliminary investigation has been made of soil treatments for the control of Collembola, which caused severe damage to germinating vegetables in Nelson. Efforts to discover the breeding-place of

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