let the residue dry and then use a stiff brush to brush the canvas - should take most of it out but if not you can then use fenwicks awning cleaner if needed but you will have to rinse well with clean water before reproofing the area treated.
Yep have to agree with Jan P ,after being under trees for a couple of weeks earlier this year the top was in a terrible mess with bird poo and tree sap etc , put up on drive at home and with tall steps used hosepipe and long handled stiff brush,and it came up like new again,
Absolutely agree! Try the natural methods first .... only go for a cleaner as a last resort .... I had to ... with great results ... and ... reproofed four years ago .... never touched again ... still completely waterproof, tested thoroughly this summer in a couple of mega storms!