Birch saplings next to a flower don't have a chance to grow with a bee nest

Summary:
Birch saplings next to a flower don't have a chance to grow with a bee nest like oak saplings.

Steps to Reproduce:

1. Place down multiple birch saplings next to flowers
2. Wait for the saplings to grow (increase randomtickspeed to 1000 to speed this up)

Observed Results:
None of the saplings have grown with a bee nest.

Expected Results:
Birch saplings should have a chance to grow with a bee nest, just like oak saplings.