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retarded maturity. The highest yields of deseeded straw were from plots receiving potash. Detailed examination of results awaits completion of scutching. Pot Trials.—Pot trials were carried out in the Wheat Research Institute glasshouse to test the effect of varying proportions of L, P, K, N, and B. This material has not yet been examined. Weed Control. —Extensive trials were carried out with Sinox, Sinox plus sulphate of ammonia, and Amnox. The two latter are more rapid in action than Sinox, and are consequently less liable to be washed off by rain falling soon after application. Also, about half the quantity per acre is required to give the same control of weeds as for Sinox, and as the cost of the material is approximately the same, the cost per acre is halved by their use. Unfortunately, the margin between the minimum amount required for a satisfactory kill of weeds and the maximum amount tolerated by flax is very narrow, and the optimum quantity varies considerably with weather conditions, so that at present none of these weed-killers can be recommended for general use. Attempts will be made to devise some method of ascertaining rapidly the correct application under any given conditions. Plant Establishment. —Preliminary trials are under way to find some way of estimating the probable field establishment of any sample of seed. It is known that this may vary widely from the percentage germination in the laboratory. Many factors arc involved, but it may be possible to devise some test that will give a better indication of potential field establishment than the present standard laboratory germination test. Lucerne The nucleus area of Strain B was again harvested and the seed distributed for further trials both in New Zealand and in Great Britain. The increase area grown at the college provided approximately 6001b. of seed, which was distributed by the Department of Agriculture for sowing further seedmultiplication areas. The mass-selected strain of the spreading species, Medicago glutinosa, was harvested and the seed obtained passed over to Lincoln College for trial and further increase if warranted. Potatoes _ Sixty hydrid lines were propagated in a yield trial at Lincoln and in small increase plots at Kaituna. Most of these are crosses between Katahdin and other imported commercial varieties, local commercial varieties, or S. andigenum, a South American species. A large proportion of the lines have become infected to a more or less degree with one or other of the virus diseases, but, nevertheless, many outyield the control, Aucklander Short Top, which is the most popular variety grown commercially. Mangels, Carrots, Chicory, and Beans Small areas of Yellow Globe mangel, of Holmes Improved carrot, of chicory, and of the Hawkesbury Wonder bean were grown for seed-production from reselected stocks. Sunflowers The growing of oil-seed crops in this country would provide additional cash crops for a section of the farming community, and now that an extraction plant lias been established in Dunedin it is possible that the acreage sown with linseed will be extended. It is possible, also, that the growing of other oil-seed crops may be warranted, and one which seems worth while investigating is the sunflower. Extensive acreages are grown in Russia and Canada, and an effort is being made to popularize the crop in Great Britain. Sunflower-seed oil is expressed from the seed of the cultivated plant, Helianthus annuus, the cold pressed oil being used for edible purposes and the hot pressed oil or solvent extracted oil being suitable for soap-manufacture ; the oil-seed cake remaining after pressing is suitable as a cattle food, especially if the seeds have been decorticated before pressing. To determine whether the crop might be grown successfully under Canterbury conditions two black-seed varieties introduced from Great Britain and a stripe-seed variety purchased locallv were sown in small plots. All varieties developed satisfactorily, and, although flattened during a south-west storm, set seed prolifically ; the plots have not yet been threshed, but the yield prospects are good. It is considered that the black-seeded types are preferable to the stripe-seed form for seed-production purposes. Recently further seed samples were received from overseas, and future work will be concerned with isolating the most suitable variety and in determining whether the crop can be grown economically on a commercial scale. Vegetables It is generally recognized that the quality of the seed of many vegetable varieties offered for sale is far from satisfactory, and it has been considered that an effort should be made to correct this position. As a preliminary step, therefore, a series of varieties of a number of crops is being studied with a view to possible selection and seed-production. This could become a major project. Rye-grass and Clover On behalf of the Grasslands Division, Palmerston North, 5 acres of short-rotation rye-grass (HI), 4 acres of Italian rye-grass, 2J acres of perennial rye-grass, 1 acre of timothy, and 1 acre each of Montgomery red clover, broad red clover, and white clover were grown for seed-production purposes. BOTANY DIVISION Director : Dr. H. H. Allan Identification and Advice Nearly two thousand specimens were reported on. Scentless wild onion (Nothoscordum fragrans) was found to occur in several localities. This species has given much trouble in certain arable areas in Australia. Two Australian species of Dantlionia were found to be established on hill country near Blenheim, one of which gives promise of being definitely useful.

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