That should be OK, it isn't too large. What file type is it? If it is something other than a .jpg (or one of the other file types supported: bmp doc gif jpe jpeg jpg pdf png ppt psd txt xls zip) then try re-saving it as a .jpg and try posting again.
if a forum member would like to email me, i could attach the pic. It is a tree in our development on the Aegean coast, Turkey, it has heart shaped green leaves with catkins with cotton texture in spring, it is 10 - 15m tall.
Populus x canadensis (Hybrid black poplar); a hybrid between the P. deltoides and the European/Asian P. nigra. Very commonly planted in Europe, whereas pure P. deltoides is almost never planted here.
