Take note of odd things to learn and remedy problems
Lilac broom and oak canker. Found 'em
while pruning, took pictures, went home, researched them...
The broom is caused by a microorganism and will gradually kill
the shrub. Common lilacs are tolerant of it but many of the others
including dwarf 'Miss Kim' (Syringa pubescens patula) and
tree lilac (S. reticulata) are susceptible. Ash trees
(Fraxinus) are also susceptible.(We in ash-less, emerald
ash borer infested Michigand tend to be surprised to realze that
some regions still have thriving ash trees.) So don't prune
between a lilac that shows these symptoms and any other lilac or
ash without sterilizing your clippers and saw.
Belw: The proliferation of weak and dead twigs at the base
made us say, "What?!"
Below: When we got home we searched our books and on line
for the keywords lilac/Syringa, proliferation
Thank you, University of Minnestoa Extension!
Oak canker fungi get a start on weak young (barkless) twigs.
Unless the majority of branches are affected, it's not a big
problem for the tree, which outgrows an infection or sheds badly
damaged twigs. This tree was indeed letting the few affected
branches atrophy; we pruned them out but the tree was doing that