101 Questions answered
Early Warning Signs of Mallee Seeps: What to Look For and How to Confirm
There are a few clues that a Mallee seep is forming, and if you catch it early, you can stop it before it causes soil degradation and productivity loss. In the paddock you might see:
- Patches of increased plant growth, and staying greener as surrounding crop dries.
- Waterlogged areas.
- Ryegrass invading crops and pasture areas.
- Plant stress and poor growth beginning in the centre of affected areas.
If you think seeps are forming, then look at NDVI images throughout October and November. Patches of extended crop growth indicate roots are accessing perched water tables. Look at multiple NDVI images to confirm the pattern, and use your paddock knowledge to check what you’re seeing. For example, perennial vegetation can also look like a seep is forming.
The AgriSolve platform (free) has built-in instructions for using satellite images to identify Mallee seeps, as well as a tutorial video.
Then, dig a hole to check whether there is any obvious perched water table within the top two metres of soil. You might find water, or just some sloppy clay. If you do, it’s a Mallee Seep. This link explains how to assess seeps it the paddock. Use the Mallee Seeps decision tree to work out the best management options.
