Hi Cam,

Thank you for reaching out to Ask Extension with your questions about your Smoketree/Smokebush. 

Based on your pictures, I do not see any symptoms of verticilium wilt in your leaves. The Lilla Smokebush is usually one of the purple varieties and since the leaves on yours are mostly green, it leads me to believe yours has been stored in shade, rathar than full sun. Smokebush tend to lose their purple coloring in shade. These plants can often have a slightly different colored leaf margin, but I think you are seeing it more due to the greener leaves. The damaged leaf with the necrotic spot does not look like a verticillium wilt symptom. It looks like the leaf was torn and damaged somehow (shipping & handling? planting? an animal?). 

Your stem photo does not look to have the telltale signs of staining in the sapwood (which would be the white ring, inbetween the green and the middle "heartwood". The angle that it was cut is misleading though. I see the area at the bottom left that looks to be gouged in the white "sapwood" which makes it appear like it might be stained, but i think it's just a shadow from the gouge. 

Below is a link to a publication that explains the symptoms of verticilium wilt. Take a look at the pictures because there is an example of Verticillium Wilt on Cotinus coggyria, so you can see what the vascular staining looks like.

https://ag.umass.edu/landscape/fact-sheets/verticillium-wilt 

If you are still unsure as to whether you have VW or not, you can send a sample to be tested. Here is more information:

https://agsci.colostate.edu/agbio/plantclinic/ 

I hope this helps,

Dawn

Dawn,

Thank you for getting back to me. The information is very helpful and I sincerely appreciate the time! I'll rely on these resources for future reference as well. 

All the best,

- Cam

You are welcome!