Daily Mail have called it ‘Ashmageddon’. Could a fungus brought into
the UK with imported trees devastate our native woodland and
How can your students use their scientific knowledge to understand this threat?
Thousands of people have been outside checking ash trees for signs of infection by the fungal pathogen Chalara fraxinea and informing the authorities of their findings.
Chalara fungal spores attack the leaves first, before the disease moves up the leaf stems and into the branches and trunk, eventually blocking the water-carrying xylem vessels, starving them of moisture and killing the tree. Strict plant biosecurity rules have been implemented across the UK. A major programme of research, habitat surveying and citizen science has been proposed.
The Guardian’s Teacher Network gives a good list of resources.
Looking at ash dieback and using these resources gives you the opportunity to:
• Demonstrate to students why it is important to be able to identify plants correctly
• Practice plant identification skills and make a real contribution to research currently underway (students with smartphones can use the Ashtag app to upload sightings)
• Explore the structure and function of xylem in trees to understand why Chalara is so dangerous
• Introduce ideas about epidemiology and how disease spreads throughout populations
• Discuss the pros and cons of GM in relation to the resurrection of chestnuts in the USA through this Nature article
In addition, we have two related SAPS practicals:
In this new practical, students track down leaf pathogens under the microscope, as a starting point to consider the global impact of disease on society and the environment. The topic would make a contemporary science club activity, but is relevant to many aspects of A-level biology, such as leaf structure during the teaching of photosynthesis, productivity of crop species and reasons for using pest control.
do ash trees, bees and bats have in common? The surprising answer is in
their wings - or, in the case of the ash trees, their winged fruits . Recent research shows that the wings of these fruits, like
hovering insects and bats, generate more lift than would be expected by
regarding the wings as aerofoil sections - an example of convergent
evolution across animals and plants. In this practical, students
design an investigation to look at the relationship between the length
of winged fruits and their flight capacity. Plenty of opportunities for
data gathering and analysis!