Happy Autumn Tees Troopers!
We have just finished the final monitoring of the Himalayan balsam biocontrol for this year. As the end of the month approaches, the balsam is starting to die back, with some already wilting away.
The rust fungus biocontrol that we have used has a very complicated 5 stage life cycle; as the balsam dies back the rust on the leaves falls into the leaf litter in the ground ready to come back up on the new shoots next Spring. We will be back on the sites over the next few months for a few reasons, including monitoring vegetation over the winter.
Images of the rust fungus on the undersides of the Himalayan balsam leaves during the final monitoring.
Issues over the Winter:
Himalayan balsam creates monocultures, restricting native plants from growing meaning a reduction in biodiversity negatively impacting invertebrate populations and the animals that feed on them.
When Himalayan balsam dies back, it leaves the riverbanks bare and more susceptible to erosion over the winter months, this can be dangerous for anyone walking on the rivers that may fall in if the banks are unstable.
Silt is more prominent because of the bare riverbanks, high levels of silt into the waterways can cause issues such as deoxygenating the water, block the gills of fish and smother aquatic plants and invertebrates, starving them of light and oxygen.
In the future, the success of the rust fungus will control the balsam giving a chance for native species to grow. This last stage of monitoring has been really successful and we have seen a spread of the rust at most of the sites.
We are also hoping to continue to work with students from Newcastle University in the future to monitor the impact of the Himalayan balsam, the impact on biodiversity as well as the spread of the rust in the future!
Images of some MBiol and PHD students from Newcastle University doing monitoring, including collecting soil and light data at various sites.