Department of Agriculture, South Australia

Publisher's address :    Department of Agriculture, Box 901E, G.P.O.,Adelaide, South Australia

Contents: No. 1, May, 1963

5	Preliminary Experiments on the Reclamation of a Saline-Sodic Soil in the Jervois Area. J. S. RUSSELL and M. I. H. BROOKER.
21	A Survey of Post-Shearing Losses due to Adverse Weather Conditions, P. E, GEYTENBEEK.
31	Potato Irrigation Trials During 1959-60 Season, M. R. TILL.
38	Progress Report—Vine Trellising Trials, W. B. HARRIS.
43	An Extension Application of Parametric Budgeting in Poultry Management Decisions, ALLAN A. McARDLE and CLARK C. CATT.

Contents: No. 2, May, 1965

5	Analysis of calcareous coastal sands in the Lower South-East of South Australia in relation to their possible value as liming materials. By J. S. RUSSELL and N. J. GILBERTSON.
14	A key to the seedlings of the Cynarae commonly found in South Australia. By JACQUELINE F. M. BURFORD.
17	The relationship between time of pruning and Eutypa armeniacae infection in apricots. By W. J. MOLLER.
20	A comparison of the variability of water distribution from four fixed overhead sprinkler types. By M. R. TILL.
34	A comparison of the packout of oranges obtained in the Standard Bushel Case and the Dump Bushel Case. By M. B. SPURLING and L. D. JARRETT.
38	The root distribution of young citrus trees. By M. R. TILL and J. B. COX.
40	Progress Report: Cereal 'and other crop trials, Kangaroo Island Research Centre. By H. R. DAY.

Summaries

A series of samples of calcareous coastal sands taken from various points along the south-east coast of South Australia were analysed to determine their possible value as liming materials.

The neutralizing value of the materials was high, with a range of 60 to 95 per cent and a mean value of 84.6 per cent. Differences were found in the degree of fineness of these sands, though in all cases they were considered satisfactory for use as liming materials. The content of copper, zinc, boron, cobalt molybdenum and iron was low, and the manganese level variable.

These materials were considered a satisfactory source of lime for application to acid soils. Field experiments are required to evaluate desirable rotes of applications and whether trace elements deficiencies are likely to be induced on soils in the south-east.

A key has been prepared as an aid to separating the identity of seedlings of eleven of the thistle species commonly found in South Australia. The key has been designed for use at the "advanced" two-leaf stage: the stage at which the third leaf is about to, or is beginning to appear.

This article describes a pilot experiment conducted in an apricot orchard to determine the effect of time of pruning on
Eutypa armeniacae in faction. The data obtained suggests that infection risk is far greater in late winter than in

earlyspring: small pruning wounds (+in) made early in the period of low ascopore frequency did not become infected.

Variation in the precipitation from four overhead sprinklers was measured at the sprinkler spacing existing in a mature citrus orchard. Wind speed largely determined the variability of the precipitation from a particular sprinkler type. Because the wind conditions changed from one run to the next, differences they caused in the variability of precipitation were combined with differences between sprinkler types.

Examination of precipitation patterns at all wind speeds showed that with two-jet sprinklers, a zone of low precipitation occurred between the sprinkler lines. On the other hand, with single-jet sprinklers the area of low precipitation was close to the sprinkler head at low wind speeds, and at higher wind speeds it was mid-way between the heads. Recommendations are made for sprinklers operating under various conditions.

Some Industry representatives have claimed that the Standard Bushel Case holds a greater weight of oranges than the Dump Bushel Case; other equally experienced representatives have claimed the reverse. A trial wos set up to examine these claims and it was found that although the Standard Bushel Case is slightly smaller in internal volume than the Dump Bushel Case, the two containers hold the same weight of fruit when it is pattern packed properly.

However, slightly different grader size settings were needed for the two containers and it was found that the grader settings should be checked every day or so, and that the settings should be adjusted over the whole length of the grader during the season to suit the type of fruit.

With the shallower depth and greater width of the Standard Bushel Case, packing was easier and as a result there was a saving in time of packing.
The root distribution of Valencia orange trees on citronelle stock was examined in the autumn of their second season after planting. Results of these studies are important when considering the cultural practices of irrigation, manuring, cultivation and cover cropping in trees of this age.

Contents: No. 3, May, 1969

5	Pesticide residue trials—No. 1. By J. T. Fearn
7	Influence of nitrogen fertilizer on skin thickness of Washington navel orange fruit. By M. R. Till, J. R. Botham and V. K. Lohmeyer
9	A citrus leaf analysis survey in South Australia. By J. R. Botham and K. J. Gillespie
18	Uniformity of water distribution from undertree sprinklers. By A. C. Chappell
22	A rate of rainfall recorder. By J. A. Edwards
28	A simplified pycnometer for measuring air-filled porosity of soil. By J. S. Potter
32	An irrigation and spacing trial on tomatoes. By M. R. Till

Summaries

Dipping sheep with dieldrin to control external parasites by the saturation or tip spraying methods, results in pesticide residues in the body tissues for at least three months after application.

Differential rates of sulphate of ammonia were applied to Washington navel orange trees each year for 35 years. The internal and external diameters of a sample fruit from each of six rows of trees receiving the different nitrogen treatments were measured in August. An increase in the rate of application of nitrogen fertilizer resulted in an increase in skin thickness of fruit with the same external diameter. The increase was from 5.5 mm with no nitrogen fertilizer to 7.1 mm where 10 cwt per acre of sulphate of ammonia had been applied each year (equivalent to 2.5 lb. of actual nitrogen per tree).

During 1963 and 1964 samples of citrus leaves (Washington navel and Valencia oranges) were analysed for most of the important mineral nutrients present. The leaf samples were taken from 240 grower-owned sites in the various citrus districts of South Australia.

The uniformity of water distribution from sprinklers suitable for undertree irrigation was measured. The influence of sprinkler type, pressure, jet size and sprinkler spacing on uniformity was found. These investigations were made to assist in sprinkler selection and operating conditions for irrigation of commercial orchards.

A rate of rainfall recorder has been developed in which the time and date of incidence of each point of rain is recorded. The rainfall measuring apparatus has tilting buckets which overbalance when filled with one point of rain. Each tilt of the buckets closes electrical circuits which cause the exact time of day of this occurrence to be recorded on a time clock of the job recorder type. The apparatus is battery powered and the rainfall measuring apparatus can be connected to the time recording apparatus by a cable up to a mile in length.

An air-pycnometer has been developed to measure the air-filled porosity of undisturbed soil. Cores taken with a standard type sampler are used. Porosity is read directly from the pycnometer, the operation taking less than one minute per sample. Effects of variations in atmospheric pressure are eliminated. The instrument is simple and rugged.

At the Parafield Research Centre in the 1957-58 season, the effects of three irrigation treatments combined with three plant spacing treatments on the yield of tomatoes were measured. Increasing the time between irrigations from about every six days to about every 15 days resulted in a reduction in yield which was primarily due to a decrease in fruit size. Closer spacing at 2ft x 2ft more than doubled the yield per acre for a fourfold increase in plant number compared with a 4ft x 4ft spacing. This increase was due almost entirely to an increase in fruit number per acre. None of the interactions between the irrigation and spacing treatments was significant.

Contents: No. 4 

5	A reference group and an analysis of its farming operations 1. Identification of the group a pragmatic method. By A.E. Engel
24	A reference group and an analysis of its farming operations II. Farm practices and related attitudes. By G.J. Young, P.J. Mowatt and P.A. Heap
39	A reference group and an analysis of its farming operations III. Disparity between extension goals and the goals of farmers. By G.J. Young
43	An addendum note on the disparity between extension goals and the goals of farmers. By A.E. Engel

Summaries

A method of self-identification of a social group of farmers is outlined and data are presented that show that the group is a social group within a total community. By delineating the values and attitudes related to established farming behavioural patterns, the group has been defined as a reference group. As such it has implications of utility for agricultural extension.

Data are presented from a survey of farm practices in a social group and the related attitudes of the farmers. The nature of these attitudes reveal the methods of approach required in establishing a planned extension programme with the group.

Differences between the agricultural problems predicted for an area and the measured problems are outlined. The reasons for the differences are related to disparity between the farmers' goals and the extension officers' goals, in particular, neglect in taking into account the farmers' short resources and attitudes to risk appear to give rise to the anomaly in this instance.

More basic reasons are suggested for the difficulties experienced by extension officers in predicting the agricultural problems of an area. The reasons relate to current research techniques, organizational processes and psychological attributes of the extension officers. Solutions to the problems are offered.

Contents: No. 5, 1990

5	Identification of species of fruit-fly, by H.F. Lower
9	Spur-type apples, by R. Howles
12	Control of ring spot in Brussels sprouts, by LS. Rogers and T.J. Wicks
16	Vine development and temperature in the Barossa, South Australia, by E.W. Boehm
25	Benomyl as a spring eradicant for apple scab, by T.J. Wicks and W.J. Moller
28	Wheat response to individual nutrients in superphosphate, by C.L. Rudd
32	The reworking of Dunn's seedling apple trees, by L.C. McMaster and R.W.I. Cowley
40	Salt accumulation in a sandy soil under sprinkler irrigation, its influence on apricot tree health and its removal by teaching. By M.R. Till

Summaries

Larvae of the different fruit-fly species can be identified positively and rapidly by microscopic examination of the skeletal structure of larvae heads. The only limit to application of the method is imposed by the receipt of larvae of a species which the would-be identifier has not previously seen and whose determining characters are therefore unknown to him.

It was found that leaves from spur-type mutant branches of two apple varieties contained more total chloro¬phyll on a fresh weight basis than those of the parent.

Nineteen fungicides were screened for their effectiveness as high volume sprays in controlling ring spot (Mycosphaerella brassicicola (Duby) Oudem) in Brussels sprouts. Subsequently, four of the most promising fungicides were tested. The high volume method of application with four to six times the recommended rate of wetting agent, rather than airblast, appeared to give the best control.

Differences in the ripening periods of vines have been measured in the Barossa Hills and the Barossa Valley. The difference in the temperature during the growing period is consider—, the main factor which determines variation between the two ripening periods.

Good control of apple scab was achieved by using Benlate as an eradicant spray applied 6-8 days after the infection periods.

The effect of individual nutrients in superphosphate on wheat yield was tested on four cereal growing soils. Responses to phosphorus were obtained in all experiments, but the calcium, sulphur and zinc components did not affect yield.

An assessment of the bottom, top and side working methods of reworking apple trees was made. The method of reworking affected tree width, average shoot girth of the new variety, total growth made by the new variety and the percentage graft-take. The bottom working method was the most advantageous.

in an apricot orchard the lateral and vertical distribution of salts in the soil was determined within the area bounded by four fixed overhead sprinklers. A positive relation was found between the amount of irrigation water applied and the depth at which salts had accumulated in the soil. The effect of leaching irrigations on removal of salts was examined.

Contents: No 6 1992

5	Matric water potential and ground water levels on an irrigated pasture at Long Flat, South Australia. By P.J. Cole and C.L. Watson
8	Effect of artificial drainage on matric water potential and ground water levels at Long Flat, South Australia. By P.J. Cole and C.L. Watson
16	Changes in some physical properties of red-brown earths of different texture associated with increasing content of organic matter. By I .T. Grierson, J.W. Mine and D.J. Greenland
23	The Italian white snail... Theba pisana (Muller) in South Australia, with particular reference to its distribution in the South-East of South Australia. By Y.P. Lim and R.B. Jenkins
26	The effects on milk production and pasture yield of deferring the grazing of annual pastures by dairy cows. By D.C. Brown, D.M. McLean and J.C. Radcliffe
35	Pest management in an apple orchard. By Dr. P.E. Madge

Summaries

Metric water potentials and groundwater levels were measured on an irrigated pasture. Water potentials were considered to be either too high or too low for optimum plant growth for long periods during the year. Water tables were often close to the surface. Pasture production may have been restricted due to these soil conditions.

Matric water potential ground water level and tile line outflows were measured on a drainage trial on the Lower Murray Swamps during 1965 and 1966. Drainage appeared to be effective in decreasing water potential and lowering water tables in the first season after installation, but these effects had become small by the second year. This type of drainage system did not appear to remain effective for the soils of the Lower Murray Swamps.

Aggregate stability, rate of wetting, rate of rainfall acceptance, cohesion and porosity have been measured for paired samples of four red-brown earths whose clay contents ranged from 10-30%. The samples forming each pair had high and low contents of organic matter. Aggregate stability and rainfall acceptance were greater for the soils of higher organic matter content, irrespective of texture. Cohesion and rate of wetting did not show a consistent relationship to organic matter content.

The results indicate that an optimum level of organic matter exists for each clay content above which little improvement in physical condition occurs. Further studies are needed with a much larger number of soils. Rain¬fall acceptance appears to be the best method for use in such a study.

In a survey of the distribution of Theba pisana (Muller) in the South-East of South Australia, opportunity was taken to record presence and absence of He/ice//a virgata (da Costa) at the same sampling points. T. pisana was found to occur along a coastal band, narrow at the Coorong and broadening towards Mount Gambier. H. virgata was more widespread, its limits are not indicated in this survey. There is an indication that the two snails do not occur together in high densities.

Four groups of Friesian cows were used in a replicated experiment with two grazing management treatments: (1) continuous grazing of pastures, and (2) the deferment of pasture grazing immediately following the opening rains. All four groups of cows were fed equal quantities of grain and cereal hay. Rainfall during the experiment was abnormally low.

Cows deferred from grazing gained more weight, but produced less milk than cows grazed continuously. Average percentages of fat, protein and solids-not-fat of the milk from each treatment were not significantly different.
Dry matter yield of the Wimmera ryegrass-subterranean clover pasture was 76.6% higher under deferred graz¬ing management, and cow intakes of total dry matter and digestible dry matter were 11.6% and 10.7% greater for cows deferred from grazing than for cows grazed continuously.

It is concluded that to obtain benefit in milk yields and milk fat yields from deferred grazing management, cows must be fed a high plane of nutrition during the deferment period and the extra pasture produced must be utilized before it matures.

Observations over 2 seasons showed that good control of codling moth on apples was obtained using reduced rates of insecticides and timing applications according to flights of moths as detected by the use of lure pots.

Contents: No 7, 1992

4	The effect of method of application of superphosphate on wheat yield. By C.L. Rudd
10	The effects of exposure to prevailing strong winds on the growth of young citrus trees. By M.M. Campbell
20	Wind and its effects on citrus trees at Loxton, South Australia. By M.M. Campbell and G.A. Mills
36	Efficiency of summer superior oils in relation to the concentration of the emulsifying agent. By M.M. Campbell
43	Observations on the effects of high density populations of spiders. Principally an Lxeuticus sp., on the control of Aonidiella aurantii Mask by Aphytis me/inns, DeBach. By M.M. Campbell
44	Counts of adults of A. melinus on citrus trees before and after spraying with an emulsion containing 1% of a pre-emulsified oil in water. By M.M. Campbell.

Summaries

The results of sixteen experiments comparing yield responses to different methods of application of super-phosphate to wheat in South Australia in 1968 and 1969 are reported. The experiments compared the grain yield from superphosphate, normally drilled at seeding, with that obtained from three broadcast applications in December, March and at seeding (May-June).

Wind travel and tree damage were recorded in an orchard within which the wind travel was progressively decreased by a number of windbreaks. Protection from the wind was shown to be necessary, for the maximum growth, until young citrus trees were at least 4 years old. The optimal growth rate was obtained where the wind was reduced to less than 30% of the free travel. Young trees which were well protected from wind carried more fruits, and grew longer shoots and larger leaves. They suffered less leaf damage and were taller than exposed trees. Leaf damage occurred at any wind speed greater than zero, but more than 25% of leaves had to be damaged to cause an effect on the total growth achieved by the tree.

Examination of records of wind travel and direction at Loxton in the Riverland suggested that strong winds were more frequent during summer than winter, and that winds from the south-west were the strongest and most frequent in all seasons. The average number of occasions during any one year when wind travel exceeded 300 km a day from each quadrant was calculated. It was shown that the period of strongest winds coincided with the period when citrus leaves and fruits were most susceptible to wind damage. A comparison of returns from the exposed and protected sides of a row of trees indicated a considerable increase in the value of production on the protected side.

Experiments showed that as the concentration of emulsifier in oil increased from nil to 4.0%, the kill of red scale by emulsions of 2% of the oil in water decreased from more than 90% to 30-40%. It is suggested that this is not an effect of the size of the oil droplets in the emulsion, but that at high concentrations (3%) of emulisif¬ier (in the oil), little or no oil remains on the treated surfaces.

Counts of the numbers of lxeuticus and A. melinus individuals on 100 leaves indicated an inverse relationship between the numbers of lxeuticus and A. melinus. Counts were taken from 11 trees moving outwards from the centre of the infestation of lxeuticus.
Large populations of both Aonidiella aurantii Mask and its parasite Aphytis melinus DeBach, were present on five year-old citrus trees, eight of which were thoroughly sprayed with an emulsion of 1% of a pre-emulsified oil in water on April 5, 1971.