No, your eyes do not decieve you. The above is a genuine medieval manuscript in which a woman is harvesting a basket full of dicks from a tree.
Why?
Well, one can only presume if they weren't harvested while firm, they would go soft and eventually fall off the tree? I really don't know.
Apparently
this sort of thing happened often in medieval times, because backtracking through links, I found a post that included this carving as well:

And further research yielded this illumination:

I gathered my courage and Google image searched, and it turns out that this may not have been just some medieval superstition...
there is modern photographic evidence of this happening with a passion fruit tree in Brazil:


But that's not all! This has happened on
at least three other types of trees:



So yeah. I learned something tonight.
Penises grow on trees. Nature. Well then..