Grass & ferns have the tag #minecraft:mineable/axe

Can confirm. They should be in the #mineable/hoe tag for consistency.

Can confirm in 1.17.1 Release Candidate 1.

Relates to MC-227258.

This has been fixed for flowers but now for grass & ferns.

I can confirm this behavior in 1.18 Release Candidate 3.

Here's a potential fix regarding this issue. The following is based on a decompiled version of Minecraft 1.17.1 using MCP-Reborn.

Potential Fix:

In the net.minecraft.data.tags.BlockTagsProvider.java class, simply removing Blocks.GRASS, Blocks.TALL_GRASS, Blocks.FERN, and Blocks.LARGE_FERN from the MINEABLE_WITH_AXE block tag should resolve this problem. The correct line of code within its class should look something like the following:

net.minecraft.data.tags.BlockTagsProvider.java

public class BlockTagsProvider extends TagsProvider<Block> {
   public BlockTagsProvider(DataGenerator p_126511_) { super(p_126511_, Registry.BLOCK); }

   protected void addTags() {
      ...
      this.tag(BlockTags.MINEABLE_WITH_AXE).add(Blocks.NOTE_BLOCK, Blocks.ATTACHED_MELON_STEM, Blocks.ATTACHED_PUMPKIN_STEM, Blocks.AZALEA, Blocks.BAMBOO, Blocks.BARREL, Blocks.BEE_NEST, Blocks.BEEHIVE, Blocks.BEETROOTS, Blocks.BIG_DRIPLEAF_STEM, Blocks.BIG_DRIPLEAF, Blocks.BOOKSHELF, Blocks.BROWN_MUSHROOM_BLOCK, Blocks.BROWN_MUSHROOM, Blocks.CAMPFIRE, Blocks.CARROTS, Blocks.CARTOGRAPHY_TABLE, Blocks.CARVED_PUMPKIN, Blocks.CAVE_VINES_PLANT, Blocks.CAVE_VINES, Blocks.CHEST, Blocks.CHORUS_FLOWER, Blocks.CHORUS_PLANT, Blocks.COCOA, Blocks.COMPOSTER, Blocks.CRAFTING_TABLE, Blocks.CRIMSON_FUNGUS, Blocks.DAYLIGHT_DETECTOR, Blocks.DEAD_BUSH, Blocks.FLETCHING_TABLE, Blocks.GLOW_LICHEN, Blocks.HANGING_ROOTS, Blocks.JACK_O_LANTERN, Blocks.JUKEBOX, Blocks.LADDER, Blocks.LECTERN, Blocks.LILY_PAD, Blocks.LOOM, Blocks.MELON_STEM, Blocks.MELON, Blocks.MUSHROOM_STEM, Blocks.NETHER_WART, Blocks.POTATOES, Blocks.PUMPKIN_STEM, Blocks.PUMPKIN, Blocks.RED_MUSHROOM_BLOCK, Blocks.RED_MUSHROOM, Blocks.SCAFFOLDING, Blocks.SMALL_DRIPLEAF, Blocks.SMITHING_TABLE, Blocks.SOUL_CAMPFIRE, Blocks.SPORE_BLOSSOM, Blocks.SUGAR_CANE, Blocks.SWEET_BERRY_BUSH, Blocks.TRAPPED_CHEST, Blocks.TWISTING_VINES_PLANT, Blocks.TWISTING_VINES, Blocks.VINE, Blocks.WARPED_FUNGUS, Blocks.WEEPING_VINES_PLANT, Blocks.WEEPING_VINES, Blocks.WHEAT).addTag(BlockTags.BANNERS).addTag(BlockTags.FENCE_GATES).addTag(BlockTags.FLOWERS).addTag(BlockTags.LOGS).addTag(BlockTags.PLANKS).addTag(BlockTags.SAPLINGS).addTag(BlockTags.SIGNS).addTag(BlockTags.WOODEN_BUTTONS).addTag(BlockTags.WOODEN_DOORS).addTag(BlockTags.WOODEN_FENCES).addTag(BlockTags.WOODEN_PRESSURE_PLATES).addTag(BlockTags.WOODEN_SLABS).addTag(BlockTags.WOODEN_STAIRS).addTag(BlockTags.WOODEN_TRAPDOORS);
   ...

The description of this ticket seems to imply that flowers are also part of the tag but I can't reproduce this in 22w14a. Grass does still seem to be part of the tag in this version, however.

Can also reproduce in 22w17a. Can flowers be removed from the description of this ticket?

Can confirm in 1.19.

Can confirm in 1.19.2.

Can confirm in 1.19.4