This is a Satsuki nearing the end of it’s flowering period and will soon need to have all the flowers removed. This process should also be done with other Rhododendron varieties. One can be viewed on an older post.
Here’s a typical flower on my satsuki. It’s getting a but tatty looking and will soon fall.
This only means that the flower petals will fall. Left behind is usually the ovary and the stigma. Below you can see the same flower bud with the petals removed and the other bits, also including the stamen, remaining.
This is the part that must be removed to avoid the tree wasting energy in producing seed. This can be picked out with fingernails but it is best to remove with scissors as shown below by cutting through the pedicel or stock behind the pod.
This is the removed seed head. If you get it early, it is still small and a lighter colour.
Below is a typical sight on my satsuki at the moment. The petal has fallen and the pod with style and stigma is all that remains. Notice it is bigger than the one above already and is a slightly darker colour. Energy is being wasted.
Hope this helps explain the process.