You would have to plant a seed. It grows roots. A flower grows. The visual is a picture of all 3 steps, planting a seed, roots growing and finally a flower. This picture is just like reading prefixes, roots and suffixes.
Prefixes have to come first, so that is just like planting the seed.
They can come at the beginning or the end of a word. Suffixes come at the end of a word just like when the flower finally grows. So when you have a prefix, it will be first, the root will be next and the suffix last. A list for keeping a record of the prefixes, roots and suffixes taught is provided and can be used in place of the pre-tree. This list has the same pictures as the visual to help the student remember.