Long hot summer
Patricia Gill, Denmark Bulletin
Forests and reserves around Denmark have been hit by a ‘forest collapse’ event as the region struggles through a dry six months and feed for farms is depleting.
Murdoch University fire and plant ecologist Dr Joe Fontaine says Denmark and South Coast regions may not be having the driest spell on record but the ecology was suffering due to an unusually long summer.
Dr Fontaine had heard how pockets of forest collapse were present in the Mt Romance, north-west of Denmark, and in the Mt Frankland National Park, particularly where there were big granite outcrops.
Those patches were often rocky with shallow soil therefore the plants ran out of water first.
Dry conditions throughout WA have led to what is believed to be the world’s first ‘forest collapse’ event in 2010 and 2011 and ecologists believe another event on a much bigger scale might be looming.
This had been likened to a coral bleaching event on land.
Coral bleaching is caused by marine heat waves while the land events follow extremes of heat and dry.
Dr Fontaine has been studying signs of tree and plant stress from Albany to Shark Bay since February and warns that ‘attention to country’ was necessary with some activities best delayed.
They included hiking, especially over moss-covered granite, always a fragile ecosystem, and allowing some plants to die rather than watering them.
Long dry has forests in crisis
“People living on a bush block who are seeing things die may need to think about thinning them out,” Dr Fontaine said.
Watering from aquifers and depleting these sources should be balanced against the value of keeping plants alive.
This was particularly the case around Perth with dying avocado and grapes which were being kept alive with ground water.
Likewise, people living in forested areas might remove moisture-stressed trees as an intervention.
Denmark farmer Ross Thornton said he had bought in his seventh truckload of hay for the season – this one from Hyden in the Wheatbelt – and there was no more hay available Statewide.
The hay had cost $320 a bale delivered to the property to be fed to 100 breeders.
A conversation with the truck driver had revealed that recent rainfall of 120mm at Hyden had had little effect in the hot and dry season.
“And they’re used to the dry up there but down here we’re not,” Mr Thornton said.
Denmark would normally have substantial rainfall in April while at Hyden the first rains would be later.
Mr Thornton had spoken to farmers whose dams had turned to mudholes and they were losing stock which were getting bogged in the mud.
Hay from the Wheatbelt was now being channelled into the local market rather than for export and feed mills.
Mr Thornton said he was fortunate to have two running creeks on his property but this was not the case with many local farmers.
But with no chance of rain for some time, and the possibility of a ‘late break’, the replenishment of pasture would be slow.
“A break in late May will mean that the ground is cold and the feed will not grow,” Mr Thornton said.
People who may have noticed trees and other flora drying and dying are urged to become citizen scientists and use the Dead Tree Detective, a website where locations and photos can be uploaded to help track this event.
This article appeared in the Denmark Bulletin, 18 April 2024.
