| Researcher(s) |
Bill Bowden (West Midlands Group) Chris Wilkins (West Midlands Group) |
|---|---|
| Year(s) | 2016 |
| Contributor | West Midlands Group |
| Trial location(s) |
Badgingarra, WA
|
To determine the long term effects of 1980 P treatments on soil fertility.
The trial was dogged by non-wetting and kangaroo grazing problems and so the bioassay of the residual effect of the original source of P treatments was poor..
Recoveries of applied phosphorus in the surface layers was poorest for the water soluble, plant available source superphosphate which had large leaching losses below 50 cm. the less immediately available but citrate soluble source retained more P in the surface layers while the very insoluble C ore source produced poor growth but had only very low P leaching to depth. The compromise in choice of source, between plant availability and leaching into the ground water and subsequently the waterways, is well illustrated by this trial
As a rule, soil fertility factors (non-wetting, organic carbon, CEC, soil organic nitrogen, acidification etc were all more affected by length of pasture ley than by pasture composition and cumulated production. Cross plot transfer of surface soil may well have affected this finding..
| Lead research organisation |
West Midlands Group |
|---|---|
| Host research organisation | N/A |
| Trial funding source | NACC |
| Related program | N/A |
| Acknowledgments |
Thanks go to the 1980 instigators of the trial: Mike Baker and Mike Bolland. Thanks also to the landowners, David Frankland, then Geoff Pearson, to the funders, NACC, and to the sponsors, the West Midlands Group and DAFWA. |
| Other trial partners | Not specified |
| Crop type | Cereal (Grain): Wheat |
|---|---|
| Treatment type(s) |
|
| Trial type | Experimental |
| Trial design | Replicated |
| Sow rate or Target density | 100kg/ha |
|---|---|
| Sowing machinery |
Precision plot seeder with multiple runs, wheel on tyne. |
| Sow date | 9 May 2016 |
| Harvest date | Not specified |
| Plot size | 2.5m x 60m |
| Plot replication | 3 |
| Fertiliser |
The nitrogen was applied by hand in 2015 (100kg Urea/ha about 4 weeks after seeding) and as a liquid (80L of UAN/ha, 3 weeks after seeding) in 2016. |
| Herbicide |
Pre-emergent weed control was used in both years and broadleaf spray successfully controlled late emerging capeweed and blue lupins in 2016. |
SILO weather estimates sourced from https://www.longpaddock.qld.gov.au/silo/
Jeffrey, S.J., Carter, J.O., Moodie, K.B. and Beswick, A.R. (2001). Using spatial interpolation to
construct a comprehensive archive of Australian climate data , Environmental Modelling and Software, Vol
16/4, pp 309-330. DOI: 10.1016/S1364-8152(01)00008-1.
