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AERODROME ADVISORY SERVICE Advice has been given to enable aerodrome surfaces throughout New Zealand to be kept in satisfactory condition. Better results may be anticipated now that sulphate of ammonia is more readily available. LINCOLN SUBSTATION The new pasture, hay, and dual-purpose cocksfoots, bred at Palmerston North, have proved over four years to yield about 15 per cent, more feed than the Government stock strain. In cocksfoot, high yield of seed usually means low yield of feed, as in Danish cocksfoot, and this is true of the new strains, which give a rather lower seedyield than Akaroa though they produce more feed. Fortunately, this slight reduction in seed-yield can be more than made up by the application of sulphate of ammonia, which, in a recently concluded trial, more than doubled the seedyield. A new trial has been started to test the effects on seed-production of different rates and times of application of manure. Intensity of grazing greatly influences the proportions of grasses and clovers in the pasture. Studies are in progress to determine more precisely the effect on the composition of the sward of (a) continuous grazing, (b) grazing when the grass reaches a height of 4 in., and (c) grazing at a height of 10 in. In addition to the effect of grazing on the pasture, information, is required on the effect of animal manure compared with artificial fertilizers. For this, various forms of lime, phosphate, potash, and nitrogen are being applied at rates equal to those found in the dung and urine from sheep grazing the trial area. Total yields and dry-matter yields will be measured, and botanical analyses made. A single-plant area has been established of breeding material of perennial, Italian, and short-rotation rye-grass, cocksfoot, white clover, Montgomery red clover, and broad red clover. Numerous other manurial and management trials are in progress, and the turf advisory service to sports bodies and aerodromes is being continued. OTHER SUBSTATIONS Pasture-management trials are now operating fully on plots laid down in autumn, 1949. Herbage-production from strains of grasses and clovers show that no strains tested are superior to those selected at Palmerston North. Progeny testing of breeding-material has not proceeded far enough to show whether the behaviour of the various progenies at Gore is similar to their behaviour at Palmerston North. The effect of clovers on the grass of the sward is being studied, and indications are that red clover is not as efficient a nitrogen provider as white clover. Areas have been sown in pasture to determine the influence on both pasture and stock of various systems of pasture managements. Persistency of both perennial and short-rotation rye-grasses is being studied in these trials. POLLEN FOR MEDICAL INSTITUTIONS A total of 1,009 grams of grass pollens has been supplied this season to medical institutions for further work on hay-fever.

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