H.—29.

Among the miscellaneous samples may be mentioned a soil from Waitakaruru, Hauraki Plains, which., although it had had no manurial treatment, was exceptionally rich in total and available phosphoric acid, the figures being 040 per cent, and 0-16 per cent, respectively. Samples of mud from the Havelock mud flats (Pelorus Sound) which it was proposed to dry and bag up for use as a fertilizer were found on analysis to have only about 0-2 per cent, phosphoric acid and 1 per cent, of carbonate of lime. A sample of Tarawera mud used for top-dressing the bowling greens in the Government Gardens at Rotorua was shown to be rich in lime but rather light in texture, while Tuakau soil used for a similar purpose was deficient in lime but contained a good proportion of clay. It was considered that a mixture of the two soils would be useful. Fertilizers. During the year 187 registration certificates were issued to 98 manufacturers and brokers, with 255 branches, covering 899 different brands of straight and mixed fertilizers and fertilizing materials. The number of secondary vendors, including merchants, storekeepers, dairy companies, &c, amounted to 685, with 216 branches A scale of brand-registration fees chargeable to manufacturers, importers, and brand owners was brought into operation at the beginning of July last year. As a result of this regulation there was a very considerable reduction in the number of brands on the register for the period under review, and much correspondence was involved with vendors in brand and fee questions. The charging of fees has had some effect in preventing the registration of a large number of brands which were not being sold, and the cutting-down of different brands covering the same or similar formulae can be considered, as a step in the right direction towards the standardization of the great number of fertilizer recipes for different crops. It is still believed that a reduction of brands could be further extended without disadvantage to either manufacturer or consumer. Already as a result of the reduction of brands sold by individual vendors the schedules of fertilizers given in invoice certificates issued to purchasers are now much more satisfactory in that they are easier to follow. The co-operation of analysts in private practice has been secured in connection with the framing of analytical reports on fertilizers in terms of the Act. This should assist to some degree in the standardizing of statements of quality in advertising matter. More interest than usual was noted in the sale of animal organic fertilizers derived as by-products from meat and boiling-down works, &c. It is to be hoped that before long the Dominion market will sufficiently absorb all locally produced manures of animal origin without there being any necessity to send any to far-distant foreign countries. The question of agricultural-lime products being brought under the scope of the Fertilizer Act has been under active consideration. Lists of lime vendors and reports bearing on proposed lime legislation were sent forward from this office from, time to time. A good deal of information has been gathered in regard to the sale and composition of numerous stock-licks and foods on the market, reports being forwarded when requested. Among the various other matters receiving attention were—(l) Technical advice and assistance in connection with a synthetic process of basic-slag manufacture. Limited quantities of the slag donated for experiment are being tested in comparison with other phosphatic fertilizers on small plots situated on dairy pastures adjacent to Wellington. Growth effects following the treatment with the synthetic material are now commencing to be manifested and to date the results may be regarded as satisfactory. (2) The amount of fat in organic manurial products from meat-works, fish factories, &c, is of importance to the Dominion as fairly large quantities of such products are still being used every year. The opinion of several overseas authorities has been obtained on whether or not the presence of fat or oil in appreciable amount in organic fertilizers is detrimental in the soil to the assimilation of plant-foods. While the point still appears to be somewhat obscure and opinions are divided, fat or oil must surely be regarded as make weight or unwanted matter in a fertilizer, and its elimination as far as possible would appear to be desirable. The fat content of local organic products varies considerably, but the average would be about 12 per cent, to 15 per cent. If this amount could be economically reduced to 2 per cent, or 3 per cent, substantial savings would be effected both to consumer and manufacturer alike. A report on the subject is at present being completed. (3) Weed-killer trials under difficult conditions were conducted with a large number of chemicals in an endeavour to find a cheaper, better, and less dangerous substitute for sodium chlorate. Approximately ninety tests, mostly under field conditions, were made with thirty-six different substances, including a large number of oxidizing substances with properties somewhat similar to but less dangerous than sodium chlorate. Many of these were tried on ragwort at different strengths either with diluent or fertilizer or in solution. Using sodium chlorate as a standard of comparison the following were prominent among certain groups of substances potent in their action in killing ragwort: (1) Hypochlorites of sodium and potassium ; (2) chromates of sodium and potassium ; (3) thio-cyanates of ammonia, sodium, and potassium. Further experiments with these and other promising chemicals will be proceeded with if facilities and assistance are available. Inquiries have been received relative to the establishment of dyeing with plant products as a home industry. One of the chief difficulties was the obtaining of locally grown plants yielding good blue and green dyes. It was suggested that I satis tinctoria could be grown to supply the blue used by the ancient Britons under the name " woad," and some seed of this plant was obtained from England for the purpose. Plants are now growing in local gardens. For green dye, privet was suggested. Owing to several accidents attending the use of sodium chlorate for weed-killing and various requests for information, a leaflet was prepared and printed for distribution to manufacturers and

57