In other words, she does absolutely NOTHING.
The rainforest is just doing its thing anyway.
What's this "adopting" crap?
Nodding in agreement with a bunch of trees?
Probably the same type of scam as "buying" an acre of land on the moon. :-)
It’s probably something like what these folks do:
http://adopt.nature.org/faq.html
Basically, people donate, they use the donation money to buy plots of land in areas considered vulnerable - which probably means those that might get developed (deforested, etc.), and they keep ownership of that land to prevent such development.
As a biologist, I’m not sure if that’s quite enough to offset the carbon emissions of a race car, in that you’re right - the trees were already there, she’s just paying so they stay there.