Field studies on effect of soil conditioners and mulch on runoff lrom kaolinitic and illitic soils

Runoff plots (1 - 5 m2) were constructed at three sites where crusting, runoff and erosion are severe problems. The effect of surface application of phosphogypsum (PG), polyacrylamide (PAM) and mulch cover on runoff during natural rainstorms were studied. Runoff percentage from control (bare) plots in some rainstorms exceeded 90% of the rainfall. The annual runoff from control plots ranged between 33 and 73% of the annual rain. Mulch was highly beneficial in reducing runoff, indicating that seal formation restricted water penetration rather than hydraulic properties of the profile. PG reduced runoff to 0.15-0.82 of the untreated plots. The efficiency of PG in reducing runoff was inversely correlated with rainstorm intensity. The beneficial effect of PC in reducing runoff lasted throughout the rainy season. Its beneficial effect terminated during the consecutive season in the Irene site when the cumulative rain depth exceeded 700 mm. PAM treatment reduced annual runoff by two to three fold in comparison with the control treatment. The effect of PAM on diminishing runoff in the rainfall simulator studies was more pronounced than in the field conditions.

Comparison of phosetyl-Al, phosphorous acid and metalaxyl for the long-term control of Phytophthora root rot of avocado

Avocado trees affected by root rot caused by Phytophthora cinnamomi Rands recovered rapidly when given injections into the trunk of phosetyl-A1 or phosphorous acid. Injected trees had greater yields(47.9-67.5 v. 4.3 kg fruit per tree) and lower leaf chloride levels (0.8-2.4 v. 4.2%, w/w) than controls in the third season after starting treatment. Phosphorous acid residues (21-83 mg kg-1) were detected in fruit from injected trees. Metalaxyl applied to the soil twice each growing season successfully controlled root rot for the first 2 seasons, but there was a significant resurgence of decline symptoms after the third consecutive season of use.

Excavations at Kish, 1928–9

LAST winter was the seventh consecutive season of the Herbert Weld (for Oxford) and Field Museum Expedition at Kish, when Mr. Watelin, in charge of the excavations, reached virgin soil 28 feet below plain level, and 61 feet below mound level. At the end of the sixth season (1927–8), Watelin, Mr. Henry Field, and Mr. Eric Schroeder found the series of vaulted brick tombs and four-wheeled chariots, described in Art and Archœology, 1928, November, pp. 155–68. The Neo-Babylonian reconstruction of the temple Ehursagkalamma by Nebuchadnezzar and Nabunidus, whose pavement lies 20 feet below mound level, may be seen in the back ground on the photograph in Illustrated London News, 1930, 8th February, p. 206. Where the deep wide excavations now appear, stood a large mound, when Mr. Mackay and I first attacked this great tal in 1925. This mound marked Z on my plan of Kish, contained above the red stratum or temenos platform (see below) a ruined building from the periods of Sargon of Agade and the first Babylonian dynasty. Outside the wall near the ziggurat we found that year a marble statuette after the style of the one published in Art and Archœology, 1928, November, p. 160, with the cartouche on the right shoulder as figured on p. 602.

Herring Investigations at Plymouth. V. The Plymouth Winter Fishery during the Season 1927–28

During the winter of 1927–28 the progress of the herring fishing at Plymouth was followed for the fourth consecutive season. A diary of market events was again kept by Mr. A. J. Smith of the Laboratory staff, while statistics of commercial landings and of the number of visiting drifters were kindly supplied by Mr. T. Edser of the Statistical Department, Ministry of Agriculture and Fisheries, and by Mr. E. C. Nelder of the Sutton Harbour Improvement Company, respectively. In the examination of age and growth of random samples of herrings, Mr. F. J. Warren, Laboratory Assistant, again acted as recorder. Details of the methods of treatment of the data collected will be found in Part I of this series of Reports (Ford, 1).