How can I be sure that the recipient collected my trees?

If you go to the My contributions section of your profile and scroll down to the offered tree section, you'll be able to see if a tree has been collected or not underneath each tree:

Visit My contributions section here.

Collected tree

Here is how a set of trees looks when it has been collected:

Tree collect

Not yet collected tree

Here is how a set of trees looks when it has not been collected yet:

Collect Tree Banner

Please note that we deliver 2 email reminders for your tree-gifts: one 48 hours later than the first email and another one 10 days later.

If you don't want to wait for the email reminders, you can click on the orange bar to get a few options to speed things up:

Tree Link