"Daveman750" wrote in message
...
I was looking at systemic fungicides to treat dogwood anthracnose.
Would it be safe and effective to use a fungicide intended for lawns
instead of trees (spectricide immunox) that says it treats anthracnose,
on my dogwood?


It will be the same 7-10 day spray interval. All "systemic" means in this
instance is that the leaf surface absorbs a tiny bit of the fungicide
instead of it just coating the surface, not that it's carried throughout the
plant's vascular system. And the absorbed amount still has the same half
life. Spraying trees is a PIA. Better to buy resistant cultivars. If the
tree is large and has a lot of personal significance, and arborist can come
inject a fungcide into the cambrium, but that is a every 6 week interval
proceedure, and frankly, I'm not convinced that the wounds to the tree
aren't invitations to invasions of other kinds of insects and disease. And,
BTW, if a fungicide doesn't say it treats it, it usually does a poor job,
and it's actually a violation of federal law to use a pesticide in a way not
listed on the label. Immunox doesn't work very well on anthracnose or
cercospora on roses, wheras chlorothalonil does, but with risk of
phytotoxicity, increased during the warm months. But, anthracnose prefers
cool wet spring/fall weather and usually just goes away during the heat of
summer, so you could probably get by with only spraying during spring and
fall with an registered fungicide.