Healthy spring growth in mid-north does not include red gum seedlings

In September 2015 the mid-north of South Australia is a sea of green and gold, with the intense green of lush grain crops interspersed with the brilliant yellow of canola and bordered by native golden wattles and senna bushes. Streams are running and the countryside is full of healthy signs of spring.

dense green spring crops in the mid-north landscape

dense green spring crops in the mid-north landscape


On my eighth survey of red gum health in the region, this is the most water I have seen in the landscape, the best crops and the healthiest state of mature river red gums. However, there are still no signs of significant regeneration by red gums, with no new stands found since 2008.
Willochra Creek flowing between Melrose and Wilmington

Willochra Creek flowing between Melrose and Wilmington


The villains preventing regeneration of the red gums appear to be the soft spring weeds, knee-high across the landscape in all the spaces along the banks of rivers and streams where seedlings might grow. Red gum seeds need to fall from the parent tree and land on bare moist soil, where they will germinate within 24 hours and begin to grow, before ants can gather the seeds into their nests for food.
New red gum seedling surviving among rocks and weeds on the edge of Willochra Creek

New red gum seedling surviving among rocks and weeds on the edge of Willochra Creek


In addition, the river valleys of the mid-north are choked by phragmites reedbeds, currently in their dry winter state, but just starting new dense green growth for summer. Locals report that the reeds have expanded across the whole width of river channels since the 1960s, as the river flows have reduced in volume and duration, allowing the reeds to cover more potential habitat for regeneration of red gums.
dense reed beds cover the Broughton River channel near Yacka

dense reed beds cover the Broughton River channel near Yacka


The red gums are producing plenty of seed, but there is no space for seedlings to establish. Active intervention will be needed, to clear spaces for seed to fall on moist soil, to keep the competing weeds down, and to prevent stock from grazing young seedlings. Without action, there will be no new generations of red gums in the mid-north landscapes, to replace the current aging red gum communities.
New seedlings are needed to replace the magnificent giants which line the rivers and creeks of the mid-north region

New seedlings are needed to replace the magnificent giants which line the rivers and creeks of the mid-north region

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About redgumgirl

Dr Anne Jensen is an environmental consultant with a passionate interest in sustainable management of our natural resources, particularly the River Murray and wetland environments. She is particularly interested in using photographs and stories to explain issues around water and protecting natural ecosystems in terms that are understood by the wider community, so that we can manage our environment sustainably for our common future.
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One Response to Healthy spring growth in mid-north does not include red gum seedlings

  1. peterrday says:

    Any rabbit activity contributing to seedling loss?

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