That comment may be a popular wisdom version of research re salicylic acid activities in plants.

This pdf has some info; you can likely find much more:
"Salicylic acid in plant defence - the players and protagonists"
Gary Loake and Murray Grant

An extract from the above states:
"Salicylic acid (SA) is synthesised by plants in response to
challenge by a diverse range of phytopathogens and is
essential to the establishment of both local and systemic-
acquired resistance (SAR). SA application induces
accumulation of pathogenesis-related (PR) proteins. Mutations
leading to either reduced SA production or impaired SA
perception enhance susceptibility to avirulent and virulent
pathogens. However, our knowledge of the primary signalling
components activating SA biosynthesis and linking to PR
proteins accumulation is rudimentary. ..."

And an article from Fine Gardening mag is here:
http://www.finegardening.com/how-to/qa/aspirin-cures-plant-headaches.a spx

This post was edited by jean001a on Sun, Apr 14, 13 at 14:36

Old fogy here and yes the aspirin claim has been around forever it seems like lots of old gar-an-teed to work myths.

Ranks right down there with putting TUMS, egg shells, a dead fish, or any one of a hundred other weird things into the hole IMO.

Have grown thousands of tomato plants in over 50 years of gardening and not one of them needed an aspirin.

Dave

yeah but what about the Gardner Dave?, ---doesn't your arthritis ever "Kick up"?

Gary