Disease Decline Spiral updated by BAC-STOP
Researchers on our BAC-STOP project have recently published a long-overdue update to the Disease Decline Spiral Model. It draws from their research on tree decline diseases like Acute Oak Decline (AOD) which don’t have one single cause. Rather they are the result of numerous stressors which over time weaken the tree so it becomes more susceptible to infection.
The Disease Decline Spiral Model is a well-known concept originally proposed by Paul Manion in 1991. It visualises how the cumulative impact of environmental factors, pests and pathogens can lead to disease and death. BAC-STOP’s updated model adds the important dimension of time, showing how different stressors layer on over time to weaken the tree and hasten decline. They have also added the concept of the microbiome and microbial imbalance, tree carbohydrate status, and role of insects (amongst others) in predisposition, and the significance of bacteria in the final stage.
The updated model was published in a book chapter entitled ‘Temperate Oak Declines: Biotic and abiotic predisposition drivers’. It can be found in the book ‘Forest Tree Health’, the second volume of the ‘Forest Microbiology’ book series. In the chapter they write about tree decline as a concept using Acute Oak Decline as an example. They also discuss factors, like drought, soil condition and the microbiome, which can predispose a tree to spiral into decline.
The full citation and a link to the chapter can be found below.
