Rick, your tree-mail does not get deleted unless you delete it. You can create folders for your tree mail too. Click on your t-mail envelope and there's a box on the left side of the screen where you will see a place that says Folders. Click on "Manage your Folders" and you can create folders by giving them a name, i.e. "Trades" where you might want to save tree mails regarding plant swaps/trades you've made etc.
Hope this helps.
Lin
