Summary:
Terracotta, diorite, sandstone, andesite and granite interrupt root generation. Roots will simply not be generated in place of the indicated blocks, and below the generated rocks, they will continue to be generated (up to the first cave).

Examples:

Seed: 1792249514
Coords: 161 ~ 6664 (Y ≈4)
Coords: -74 ~ 6918 (Y ≈20) - Granite
Coords: -11702 113 3021 - Terracotta

Steps to reproduce:

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

Observed results:
The roots will break at the site of the diorite, sandstone, andesite and granite generation and continue slightly below (where the diorite, sandstone, andesite and granite ends).

Expected results:
Diorite, sandstone, andesite and granite will not overlap the roots.