On 24/01/2014 23:12, Nick Maclaren wrote:
In article ,
Spider wrote:

When my tree was affected the local tree surgeon said it was
Phytophthora, but I confess there are elements of Verticillium, too.
It's my bedtime now, so too late to look up verticillium images.
I'm still inclined to blame the very wet winters we've all had, and that
seems to be how Phytophthora works, as I understand it, but I don't rule
out Verticillium now that you come to mention it. More research is
required ... or another urgler.

It wouldn't surprise me if a diagnosis of Phytophthora or Verticillium
was usually based solely on the plant species, and the actual cause is
often something else entirely. As far as I can see, the symptoms are
very similar, and there are probably several other fungi that also
produce similar symptoms. Diagnosing such things reliably needs a
good laboratory and costs a lot of money.

From our point of view, it really doesn't make much difference!


Regards,
Nick Maclaren.




All true. You could always send your pics and perhaps a sample to the
labs at RHS Wisley, who do have that good laboratory and the experts to
use them.

--
Spider.
On high ground in SE London
gardening on heavy clay