Soil compaction is a serious yield and crop health concern in Australia. Measuring and determining the level of compaction can be difficult unless you have a pentometer.
Costs of Compaction:
1/ Compacted soils are harder to work and therefore use more fuel. On severely compacted soil up to 90% more power is required.
2/ Compacted soil results in poor growth and yield up to 50% as roots cannot access vital nutrients.
3/ Compaction severely limits the crops ability to access water. In dry conditions the root zone is limited reducing yield and stress tolerance. In wet conditions it encourages erosion and water logging which also effect yield and increases disease pressure increases in the short and long term.
4/ Compacted soils means more pesticides/fertiliser/water/labour/equipment/fuel are required and therefore effects the growers bottom-line.
How will the Soil Pentometer Help You?
• Where is your soil compacted?
• How server is the compaction and to what depth?
• What is the real effective tilling depth?
• How deep do I need to be tilling?
• How deep can roots and water penetrate?
• Is the current tillage system effective or been hindering production?
• Are soil amendments (compost / lime / gypsum etc.) helping?
What Causes Compaction?
Soil compaction is common on all soil types in Australia. It is generally caused by traffic via machine or animals over many years and a “plow pan” forms just below the tillage zone. Having a soil that is out of balance or low in organic matter exacerbates the problem. Traffic or tillage on damp soil speeds up the process as air is squeezed out pushing the soil particles closer together increasing compaction.
How do we Detect a Problem?
1/ Test field just before entering the field to plant/sow.
2/ Push the meter into the soil with contact and even pressure.
3/ Read the gauge in pounds per square inch (psi or MPa) every 70 mm (marked bands on probe) so you can map the depths where compaction increases or decreases. Use MPa as part of the metric system if possible.
|Soil Compaction and Root Development in psi|
|0 – 200 psi||Good Soil|
|200 – 300 psi||Average Soil|
|300 – 500 psi||Poor Soil|
|Soil Compaction and Root Development in MPa|
|0 – 1.38 MPa||Good Soil|
|1.38 – 2.07 MPa||Average Soil|
|2.07 – 3.45 MPa||Poor Soil|
4/ Perform multiple tests in the one area to get an average of results.
5/ For different soil types start a new set of tests.
6/ If there is evidence of traffic (tractor or cattle tracks, etc) you may want to do a separate set of tests in this area.
Note: When soil moisture is high reading might be mis-leading low after rain. When soil moisture is low reading might be higher in a long dry spell.
What’s the Solution?
Once you know the extent, pressure and depth of the compaction you can then look at possible solutions. For example you notice that part of a paddock is especially susceptible to compaction so you might want to decrease traffic to that area, only work on that area in drier conditions, change tillage practices, deep rip, or plant a cover crop.
• Solid construction forged alloy and stainless steel with liquid filled gauge to handle shock.
• Can test up to 870 psi (6.00 MPa) compaction. 500 psi (3.45 MPa) is poor soil.
• 550 mm stainless steel probe with 7 depth bands (70 mm apart).
Warranty and Maintenance
This meter has a 2 year warranty to be free from any manufacturing defects from the date of purchase. Please email us if there are any problems. Do not wash or expose to water. Keep in a cool, dry environment when not in use.