Silk Touch doesn't pickup Warped Sprouts

Put the summary of the bug you're having here

What I expected to happen was...:
The warped sprout should of dropped when I mined it with a silk touch Diamond Pickaxe (like Short Grass)

What actually happened was...:
No drop from item.

Steps to Reproduce:
1. Obtain a silk touch diamond pickaxe
2. Attempt to collect (break) warped sprout
3. see result