When breaking tall grass, a Sunflower appeares for a second

What I expected to happen...
The tall grass to get destroyed

What actually happened was...
For a split second a sunflower appeared in the position of the tall grass

Steps to Reproduce:
1. Place tall grass in a plains biome (Where I've witnessed it)
2. Break the tall grass
3. Look at it closely to see a sunflower appear for a second