Bruce,

That could be a bacterial result or chemical. Have you sprayed them with
anything?

Could someone have been cleaning and oversprayed and the chemical burned the
leaf surface? Is it on all the leaves or just the older/newer ones?

Last winter I cleaned the floor in my greenhouse with a power washer. Some
Phals were on the bottom shelf and the overspray of just water got on the
leaves. I didn't think anything about it since it was only water. A couple
of months later I had a bacterial marks all over the leaves. They are
outgrowing it now and the new leaves are just fine. The old leaves look
like crap and in another year they will be gone and I can show the plants
again.

Good growing,
Gene


"BruceM" wrote in message
...
Dendrobium, west facing window, 1 " faux blinds cracked about 1.5 inches
open. Plant about 6 inces from blind

Has that brown / red sand look like a spider mite infestation, but high
power magnification shows no mites, and it does not run or rinse off.
Close viewing looks like pitting of the leaves


http://home.tx.rr.com/lec/1.jpg
http://home.tx.rr.com/lec/2.jpg