Nether Giant Fungi and Basalt Spikes Don't generate in their biomes

Put the summary of the bug you're having here

What I expected to happen was...:
Giant Fungus Trees would spawn in their respective biomes and Basalt spikes in the deltas

What actually happened was...:
They look like plains biomes without any trees and the basalt deltas look like nether wastes

Steps to Reproduce:
1. go to the nether
2. go to a forest biome