Double plants can be generated in 1 block height

Summary:
Double (tall) plants can be generated trimmed to 1 block tall under a tree. Most often this happens with Large Fern in the taiga, but a similar generation can be found with double flowers.

Examples:

Seed: -1178096115296014549
Coordinates: -281 67 -498
Coordinates: -412 104 -333
Coordinates: -469 94 -448
Coordinates: 9917 63 10440

Seed: -732078047
Coordinates: -1869 62 -2581

Steps to reproduce:

1. Create a world with the specified seed.
2. Visit the above coordinates.

Observed results:
Double (tall) plants generated in a 1 block high space and became clipped.

Expected results:
Double (tall) plants should not generated in a 1 block high space to avoid clipping.

Image: