Bronze Leaf Disease
(BLD)

Bronze Leaf Disease (BLD) is a fungal disease that currently affects Swedish columnar aspen and
Tower poplar. There is concern that it could jump to our native Trembling aspen which could be
devastating to the Aspen parkland region that we live in.

BLD enters through the leaves and becomes systemic after that, meaning it can spread very
quickly.

Affected branches turn a reddish/bronze color, while the veins of the leaves remain green.
Those leave will remain on the tree well into the winter. They contain the spores that will spread
to new hosts the following spring.

Affected branches should be removed back to the truck of the tree.
*Pruning tools should be sanitized with bleach: water 1:10 solution between each cut.

The diseased wood and leaves should be bagged and disposed of.