MC-228758Most saplings cannot grow if there is a block diagonally above it
The bug
Most saplings (acacia, both azaleas, birch, spruce, jungle saplings) cannot grow if there is a block diagonally above it. This does not mangrove propagules (sometimes) or any type of mushroom/fungus. In the case of oak saplings, this prevents small oak trees from generating, but not big oak trees.
The growth is also only (generally) prevented by blocks that have a collision box, but it does affect buttons, light blocks, planks, twisting vines and even flowers for some reason. It does not affect the following blocks (list might be incomplete):
- Tall grass
- Glow lichen
- Logs
- Vines (sometimes; see MC-193318, affects certain trees)
- Wood
Linked Issues
- Unresolved
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[Mod] ampolive- 10
- 6
- Confirmed
Low- Gameplay
- Block states
- sapling tree tree-generation
1.17 - 1.21.3
1.17 1.17.1-pre1 1.17.1-pre2 1.17.1-pre3 1.17.1-rc1 1.17.1-rc2 1.17.1 21w37a 21w38a 21w39a 21w40a 21w41a 21w42a 21w43a 21w44a 1.18-pre1 1.18-pre4 1.18-pre5 1.18-pre6 1.18-pre7 1.18-pre8 1.18-rc1 1.18 1.18.1-pre1 1.18.1-rc1 1.18.1 22w03a 22w05a 22w07a 1.18.2 22w14a 22w15a 22w18a 1.19-pre2 1.19-pre3 1.19.1-pre5 1.19.2 1.19.3 23w03a 1.20.1 1.20.2 1.21 1.21.3
Created Issue:
Azaleas and flowering azaleas cannot grow if there is a snow layer or carpet one block diagonally above it
Azaleas and flowering azaleas cannot grow if there is a snow layer or carpet one block diagonally above it. I really do not know how to phrase this better. Closely relates to MC-8187.
Azaleas and flowering azaleas cannot grow if there is asnow layer or carpet oneblock diagonally above itAzaleas and flowering azaleas cannot grow if there is a non-full block diagonally above it
Azaleas and flowering azaleas cannot grow if there is a non-full block (for example, a snow layer or carpet) one block diagonally above it. I really do not know how to phrase this better. Closely relates to MC-8187 .
Azaleas and flowering azaleas cannot grow if there is a
non-full block (for example, a snow layer or carpet) oneblock diagonally above it. I really do not know how to phrase this better. Closely relates to MC-8187 .
Azaleas and flowering azaleas cannot grow if there is anon-fullblock diagonally above it
Azaleas and flowering azaleas cannot grow if there is a non-full block diagonally above it. I really do not know how to phrase this better. Closely relates to MC-8187 .
Azaleas and flowering azaleas cannot grow if there is a non-full block diagonally above it
Azaleas and flowering azaleas cannot grow if there is a non-full block diagonally above it. I really do not know how to phrase this better. Closely relates to MC-8187 .
Azaleas and flowering azaleas cannot grow if there is a non-full block diagonally above it. I really do not know how to phrase this better.
This actually affects all blocks, not only non-full ones, but I think there is already another issue for blocks preventing saplings from growing. The non-full blocks only prevent azaleas from growing, not other saplings; however, full blocks prevent all saplings from growing.
Azaleas and flowering azaleas cannot grow if there is a non-full block diagonally above it. I really do not know how to phrase this better.Most saplings cannot grow if there is a non-full block diagonally above it. I really do not know how to phrase this better. This only does not affect oak saplings.
Azaleas and flowering azaleas cannot grow if there is a non-full block diagonally above itMost saplings cannot grow if there is a non-full block diagonally above it
Most saplings cannot grow if there is a
non-fullblock diagonally above it. I really do not know how to phrase this better. This only does not affect oak saplings.
Most saplings cannot grow if there is anon-fullblock diagonally above it
Most saplings cannot grow if there is a block diagonally above it. I really do not know how to phrase this better. This only does not affect oak and spruce saplings.
Most saplings cannot grow if there is a block diagonally above it. I really do not know how to phrase this better. This only does not affect oak and spruce saplings, or blocks that lack a collision box, such as tall grass and glow lichen.
Most saplings cannot grow if there is a collidable block diagonally above it
Most saplings cannot grow if there is a block diagonally above it. I really do not know how to phrase this better. This only does not affect oak and spruce saplings
, orblocks thatlacka collision box, such astall grass and glow lichen.Most saplings cannot grow if there is a block diagonally above it. I really do not know how to phrase this better. This only does not affect oak and spruce saplings. The growth is also only prevented by blocks that have a collision box, so it doesn't affect tall grass and glow lichen, but affects twisting vines, for example.
Most saplings cannot grow if there is a block diagonally above it. I really do not know how to phrase this better. This
only does not affect oak and spruce saplings. The growth is also only prevented by blocks that have a collision box, so it doesn't affect tall grass and glow lichen, but affects twisting vines, for example.Most saplings cannot grow if there is a block diagonally above it. I really do not know how to phrase this better. This affects acacia, birch and jungle saplings. The growth is also only prevented by blocks that have a collision box, so it doesn't affect tall grass and glow lichen, but affects twisting vines, for example.
Mostsaplings cannot grow if there is a collidable block diagonally above itSome saplings cannot grow if there is a collidable block diagonally above it
Mostsaplings cannot grow if there is a block diagonally above it. I really do not know how to phrase this better.This affects acacia, birch and jungle saplings.The growth is also only prevented by blocks that have a collision box, so it doesn't affect tall grass and glow lichen, but affects twisting vines, for example.Some saplings (acacia, birch and jungle saplings) cannot grow if there is a block diagonally above it. I really do not know how to phrase this better. The growth is also only prevented by blocks that have a collision box, so it doesn't affect tall grass and glow lichen, but affects twisting vines, for example.
Some saplings (acacia, both azaleas, birch and jungle saplings) cannot grow if there is a block diagonally above it. I really do not know how to phrase this better. The growth is also only prevented by blocks that have a collision box, so it doesn't affect tall grass and glow lichen, but affects twisting vines, for example.
Some saplings (acacia, both azaleas, birch and jungle saplings) cannot grow if there is a block diagonally above it. I really do not know how to phrase this better. The growth is also only (generally) prevented by blocks that have a collision box, so it doesn't affect tall grass and glow lichen, but affects twisting vines, for example. However, it does affect buttons for some reason.
Some saplings cannot grow if there is acollidableblock diagonally above it
Some saplings (acacia, both azaleas, birch and jungle saplings) cannot grow if there is a block diagonally above it. I really do not know how to phrase this better. The growth is also only (generally) prevented by blocks that have a collision box, so it doesn't affect tall grass and glow lichen, but affects twisting vines, for example. However, it does affect buttons and light blocks for some reason.
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Some saplings (acacia, both azaleas, birch and jungle saplings) cannot grow if there is a block diagonally above it. I really do not know how to phrase this better.The growth is also only (generally) prevented by blocks that have a collision box,soit doesn'taffecttall grass and glow lichen, but affectstwisting vines,forexample. However, it does affectbuttons and light blocks for some reason.Some saplings (acacia, both azaleas, birch and jungle saplings) cannot grow if there is a block diagonally above it.
The growth is also only (generally) prevented by blocks that have a collision box, but it does affect buttons, light blocks, planks and twisting vines for some reason. It doesn't affect the following blocks (might be incomplete):
- Tall grass
- Glow lichen
- Logs
- Vines
- Wood
Some saplings (acacia, both azaleas, birch and jungle saplings) cannot grow if there is a block diagonally above it.
The growth is also only (generally) prevented by blocks that have a collision box, but it does affect buttons, light blocks, planks and twisting vines for some reason. It doesn't affect the following blocks (might be incomplete):
- Tall grass
- Glow lichen
- Logs
- Vines
- Wood
Some saplings (acacia, both azaleas, birch and jungle saplings) cannot grow if there is a block diagonally above it.
The growth is also only (generally) prevented by blocks that have a collision box, but it does affect buttons, light blocks, planks and twisting vines for some reason. It does not affect the following blocks (might be incomplete):
- Tall grass
- Glow lichen
- Logs
- Vines
- Wood
Some saplings (acacia, both azaleas, birch and jungle saplings) cannot grow if there is a block diagonally above it.
The growth is also only (generally) prevented by blocks that have a collision box, but it does affect buttons, light blocks, planks and twisting vines for some reason. It does not affect the following blocks (list might be incomplete):
- Tall grass
- Glow lichen
- Logs
- Vines
- Wood
Somesaplings (acacia, both azaleas, birch and jungle saplings) cannot grow if there is a block diagonally above it.The growth is also only (generally) prevented by blocks that have a collision box, but it does affect buttons, light blocks, planks and twisting vines for some reason. It does not affect the following blocks (list might be incomplete):
- Tall grass
- Glow lichen
- Logs
- Vines
- Wood
Most saplings (acacia, both azaleas, birch, spruce and jungle saplings) cannot grow if there is a block diagonally above it.
The growth is also only (generally) prevented by blocks that have a collision box, but it does affect buttons, light blocks, planks and twisting vines for some reason. It does not affect the following blocks (list might be incomplete):
- Tall grass
- Glow lichen
- Logs
- Vines
- Wood
Somesaplings cannot grow if there is a block diagonally above itMost saplings cannot grow if there is a block diagonally above it
Most saplings (acacia, both azaleas, birch, spruce and jungle saplings) cannot grow if there is a block diagonally above it. This does not affect oak saplings or any type of mushroom/fungus.
The growth is also only (generally) prevented by blocks that have a collision box, but it does affect buttons, light blocks, planks and twisting vines for some reason. It does not affect the following blocks (list might be incomplete):
- Tall grass
- Glow lichen
- Logs
- Vines
- Wood
Most saplings (acacia, both azaleas, birch, spruce and jungle saplings) cannot grow if there is a block diagonally above it. This does not affect oak saplings or any type of mushroom/fungus.
The growth is also only (generally) prevented by blocks that have a collision box, but it does affect buttons, light blocks, planks
andtwisting vines for some reason. It does not affect the following blocks (list might be incomplete):
- Tall grass
- Glow lichen
- Logs
- Vines
- Wood
Most saplings (acacia, both azaleas, birch, spruce and jungle saplings) cannot grow if there is a block diagonally above it. This does not affect oak saplings or any type of mushroom/fungus.
The growth is also only (generally) prevented by blocks that have a collision box, but it does affect buttons, light blocks, planks, twisting vines and even flowers for some reason. It does not affect the following blocks (list might be incomplete):
- Tall grass
- Glow lichen
- Logs
- Vines
- Wood
Most saplings (acacia, both azaleas, birch, spruce and jungle saplings) cannot grow if there is a block diagonally above it. This does not affect oak saplings or any type of mushroom/fungus.
The growth is also only (generally) prevented by blocks that have a collision box, but it does affect buttons, light blocks, planks, twisting vines and even flowers for some reason. It does not affect the following blocks (list might be incomplete):
- Tall grass
- Glow lichen
- Logs
- Vines
- Wood
Most saplings (acacia, both azaleas, birch, spruce and jungle saplings) cannot grow if there is a block diagonally above it. This does not affect oak saplings or any type of mushroom/fungus.
The growth is also only (generally) prevented by blocks that have a collision box, but it does affect buttons, light blocks, planks, twisting vines and even flowers for some reason. It does not affect the following blocks (list might be incomplete):
- Tall grass
- Glow lichen
- Logs
- Vines (see MC-193318, affects only 2x2 trees)
- Wood
Most saplings (acacia, both azaleas, birch, spruce
andjungle saplings) cannot grow if there is a block diagonally above it. This does not affect oak saplings or any type of mushroom/fungus.The growth is also only (generally) prevented by blocks that have a collision box, but it does affect buttons, light blocks, planks, twisting vines and even flowers for some reason. It does not affect the following blocks (list might be incomplete):
- Tall grass
- Glow lichen
- Logs
- Vines (see MC-193318, affects only 2x2 trees)
- Wood
Most saplings (acacia, both azaleas, birch, spruce, jungle saplings and mangrove propagules) cannot grow if there is a block diagonally above it. This does not affect oak saplings or any type of mushroom/fungus.
The growth is also only (generally) prevented by blocks that have a collision box, but it does affect buttons, light blocks, planks, twisting vines and even flowers for some reason. It does not affect the following blocks (list might be incomplete):
- Tall grass
- Glow lichen
- Logs
- Vines (see MC-193318, affects only 2x2 trees)
- Wood
Most saplings (acacia, both azaleas, birch, spruce, jungle saplings and mangrove propagules) cannot grow if there is a block diagonally above it. This does not affect oak saplings or any type of mushroom/fungus.
The growth is also only (generally) prevented by blocks that have a collision box, but it does affect buttons, light blocks, planks, twisting vines and even flowers for some reason. It does not affect the following blocks (list might be incomplete):
- Tall grass
- Glow lichen
- Logs
- Vines (see MC-193318, affects only 2x2 trees)
- Wood
Most saplings (acacia, both azaleas, birch, spruce, jungle saplings) cannot grow if there is a block diagonally above it. This does not affect oak saplings, mangrove propagules (
MC-250138) or any type of mushroom/fungus.The growth is also only (generally) prevented by blocks that have a collision box, but it does affect buttons, light blocks, planks, twisting vines and even flowers for some reason. It does not affect the following blocks (list might be incomplete):
- Tall grass
- Glow lichen
- Logs
- Vines (see MC-193318, affects only 2x2 trees)
- Wood
Most saplings (acacia, both azaleas, birch, spruce, jungle saplings) cannot grow if there is a block diagonally above it. This does not affect oak saplings, mangrove propagules (
MC-250138) or any type of mushroom/fungus.The growth is also only (generally) prevented by blocks that have a collision box, but it does affect buttons, light blocks, planks, twisting vines and even flowers for some reason. It does not affect the following blocks (list might be incomplete):
- Tall grass
- Glow lichen
- Logs
- Vines (see MC-193318, affects
only 2x2trees)- Wood
Most saplings (acacia, both azaleas, birch, spruce, jungle saplings) cannot grow if there is a block diagonally above it. This does not affect oak saplings, mangrove propagules (
MC-250138) or any type of mushroom/fungus.The growth is also only (generally) prevented by blocks that have a collision box, but it does affect buttons, light blocks, planks, twisting vines and even flowers for some reason. It does not affect the following blocks (list might be incomplete):
- Tall grass
- Glow lichen
- Logs
- Vines (sometimes; see MC-193318, affects certain trees)
- Wood
Most saplings (acacia, both azaleas, birch, spruce, jungle saplings) cannot grow if there is a block diagonally above it. This does not affect oak saplings, mangrove propagules (
MC-250138) or any type of mushroom/fungus.The growth is also only (generally) prevented by blocks that have a collision box, but it does affect buttons, light blocks, planks, twisting vines and even flowers for some reason. It does not affect the following blocks (list might be incomplete):
- Tall grass
- Glow lichen
- Logs
Vines (sometimes; see MC-193318, affects certain trees)- Wood
Most saplings (acacia, both azaleas, birch, spruce, jungle saplings) cannot grow if there is a block diagonally above it. This does not affect oak saplings, mangrove propagules (
MC-250138) or any type of mushroom/fungus.The growth is also only (generally) prevented by blocks that have a collision box, but it does affect buttons, light blocks, planks, twisting vines and even flowers for some reason. It does not affect the following blocks (list might be incomplete):
- Tall grass
- Glow lichen
- Logs
*_ Vines_ (sometimes; see MC-193318, affects certain trees)- Wood
Most saplings (acacia, both azaleas, birch, spruce, jungle saplings) cannot grow if there is a block diagonally above it. This does not affect oak saplings, mangrove propagules (
MC-250138) or any type of mushroom/fungus.The growth is also only (generally) prevented by blocks that have a collision box, but it does affect buttons, light blocks, planks, twisting vines and even flowers for some reason. It does not affect the following blocks (list might be incomplete):
- Tall grass
- Glow lichen
- Logs
*_ Vines_(sometimes; see MC-193318, affects certain trees)- Wood
Most saplings (acacia, both azaleas, birch, spruce, jungle saplings) cannot grow if there is a block diagonally above it. This does not affect oak saplings, mangrove propagules (
MC-250138) or any type of mushroom/fungus.The growth is also only (generally) prevented by blocks that have a collision box, but it does affect buttons, light blocks, planks, twisting vines and even flowers for some reason. It does not affect the following blocks (list might be incomplete):
- Tall grass
- Glow lichen
- Logs
- Vines (sometimes; see MC-193318, affects certain trees)
- Wood
Most saplings (acacia, both azaleas, birch, spruce, jungle saplings) cannot grow if there is a block diagonally above it. This does not affect oak saplings,
mangrove propagules (MC-250138) or any type of mushroom/fungus.The growth is also only (generally) prevented by blocks that have a collision box, but it does affect buttons, light blocks, planks, twisting vines and even flowers for some reason. It does not affect the following blocks (list might be incomplete):
- Tall grass
- Glow lichen
- Logs
- Vines (sometimes; see MC-193318, affects certain trees)
- Wood
The bug
Most saplings (acacia, both azaleas, birch, spruce, jungle saplings) cannot grow if there is a block diagonally above it. This does not affect oak saplings, mangrove propagules (sometimes, due to
MC-250138) or any type of mushroom/fungus.The growth is also only (generally) prevented by blocks that have a collision box, but it does affect buttons, light blocks, planks, twisting vines and even flowers for some reason. It does not affect the following blocks (list might be incomplete):
- Tall grass
- Glow lichen
- Logs
- Vines (sometimes; see MC-193318, affects certain trees)
- Wood
The bug
Most saplings (acacia, both azaleas, birch, spruce, jungle saplings) cannot grow if there is a block diagonally above it. This does not affect oak saplings, mangrove propagules (sometimes, due to
MC-250138) or any type of mushroom/fungus.The growth is also only (generally) prevented by blocks that have a collision box, but it does affect buttons, light blocks, planks, twisting vines and even flowers for some reason. It does not affect the following blocks (list might be incomplete):
- Tall grass
- Glow lichen
- Logs
- Vines (sometimes; see MC-193318, affects certain trees)
- Wood
The bug
Most saplings (acacia, both azaleas, birch, spruce, jungle saplings, mangrove propagules) cannot grow if there is a block diagonally above it. This does not affect oak saplings or any type of mushroom/fungus.
The growth is also only (generally) prevented by blocks that have a collision box, but it does affect buttons, light blocks, planks, twisting vines and even flowers for some reason. It does not affect the following blocks (list might be incomplete):
- Tall grass
- Glow lichen
- Logs
- Vines (sometimes; see MC-193318, affects certain trees)
- Wood
![[Mod] Asteraoth](../../../data/avatars/users/92886.png){kind=small}
relates to
The bug
Most saplings (acacia, both azaleas, birch, spruce, jungle saplings
, mangrove propagules) cannot grow if there is a block diagonally above it. This does not affect oak saplings or any type of mushroom/fungus.The growth is also only (generally) prevented by blocks that have a collision box, but it does affect buttons, light blocks, planks, twisting vines and even flowers for some reason. It does not affect the following blocks (list might be incomplete):
- Tall grass
- Glow lichen
- Logs
- Vines (sometimes; see MC-193318, affects certain trees)
- Wood
The bug
Most saplings (acacia, both azaleas, birch, spruce, jungle saplings) cannot grow if there is a block diagonally above it. This does not affect oak saplings, mangrove propagules (sometimes) or any type of mushroom/fungus.
The growth is also only (generally) prevented by blocks that have a collision box, but it does affect buttons, light blocks, planks, twisting vines and even flowers for some reason. It does not affect the following blocks (list might be incomplete):
- Tall grass
- Glow lichen
- Logs
- Vines (sometimes; see MC-193318, affects certain trees)
- Wood
The bug
Most saplings (acacia, both azaleas, birch, spruce, jungle saplings) cannot grow if there is a block diagonally above it. This does not
affect oak saplings,mangrove propagules (sometimes) or any type of mushroom/fungus.The growth is also only (generally) prevented by blocks that have a collision box, but it does affect buttons, light blocks, planks, twisting vines and even flowers for some reason. It does not affect the following blocks (list might be incomplete):
- Tall grass
- Glow lichen
- Logs
- Vines (sometimes; see MC-193318, affects certain trees)
- Wood
The bug
Most saplings (acacia, both azaleas, birch, spruce, jungle saplings) cannot grow if there is a block diagonally above it. This does not mangrove propagules (sometimes) or any type of mushroom/fungus. In the case of oak saplings, this prevents small oak trees from generating, but not big oak trees.
The growth is also only (generally) prevented by blocks that have a collision box, but it does affect buttons, light blocks, planks, twisting vines and even flowers for some reason. It does not affect the following blocks (list might be incomplete):
- Tall grass
- Glow lichen
- Logs
- Vines (sometimes; see MC-193318, affects certain trees)
- Wood
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is duplicated by
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relates to
Can confirm in 1.17.1. Might be related to MC-228758, but it only affects 2x2 trees.
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Thank you for your report!
We're actually already tracking this issue in MC-228758, so this ticket is being resolved and linked as a duplicate.
If you would like to add a vote or any additional information to the main ticket it would be appreciated.
Please be sure to use the search feature before creating a ticket to see if the issue has already been reported.
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Saplings are known to not care about log blocks when determining whether they can grow at all, and also grow right though them.
There is one exception, though: A log block directly above the sapling will prevent it from growing via random ticks. If there is an air block between the log and the sapling, it will grow just fine, though.
Steps to repeat:
- Place a sapling on any block it usually grows on.
- Place a Log directly on top of the sapling.
- Wait. /gamerule randomTickSpeed 1000 won't help, as the sapling never grows, unless bone meal is applied. (Notably, the sapling's age stays at 0, indicating it never even attempts to grow in the first place, rather than failing growth attempts. Compare this to MC-228758, where the diagonal block allows growth attempts to happen, but makes those fail.)
- Place another log on top of the first log and remove log right above the sapling. The sapling will grow into a tree eventually.
Expected behavior:
Since logs don't usually block growth, there should not be a difference between having a log right on top of the sapling or one block higher.
Code analysis:
SaplingBlock.randomTick() performs a light level check in addition to having a built-in random success chance. That light level check is not performed in the sapling block itself, but in the block above. Since logs are full opaque blocks, the light level will always be zero in this specific case, preventing the sapling from growing.
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This is specifically about a log blocking light and thus preventing random growth. MC-228758 explicitly excludes logs and also covers bonemeal growth, while MC-15224 is specifically about mismatched log types.
The case presented here causes the sapling to never even have failed growth attempts (which would be visible in F3 debug by its age property changing from 0 to 1), but not even attempting to grow in the first place.
This should be reopened for the following reasons:
- MC-228758 is considered valid and should serve as the strongest case as to why this should be reopened. Any block that is diagonally above the sapling shouldn't prevent it from growing.
- MCPE-127368 is considered a valid bug. Nearly all the blocks listed as affecting the azalea tree also affect every other tree in the game. Fixing it solely for azaleas would create an inconsistency in that they'd be the only trees that can grow beside said blocks. Note how most of the blocks listed there are 2-block tall blocks of vegetation.
- MCPE-93524 is also considered a valid bug and tackles a similar issue.
- This also breaks parity with Java, as some trees (for example oak) can grow if there is any block placed diagonally above the sapling.
The underlying issue for most of the cases here is that any block placed diagonally above any sapling will prevent it from growing, see MC-228758. This is technically an issue with every kind of tree in the game, but Mojang have decided that the behavior is only unintentional when it comes to azaela trees for some reason (MCPE-166948). I have requested that they review that report in hopes that they change the resolution, as fixing this solely for the azalea would create further disparity, not only with Java, but Bedrock itself.
I thought this was only an issue with azaleas and with non-full blocks, but with more experimentation it turns out all saplings (except oak saplings) do this with any (collidable) block. This might very well be a duplicate, but I didn't find anything using the search feature.
Now I recall that this also happens in older versions. If this is an intended feature, it should be the case for oak and spruce saplings as well.
The block also does not need to be immediately above the sapling, it could be up to a few (about six) blocks higher than the sapling and still prevent its growth.
Attached a test world.
I assume this should have the category "World generation" too, like most other tree-generation issues.
It's worth noting that for oak, it does prevent SMALL oak trees from generating, just not big ones. (this is a trick I've been using for a long time when I want big oaks while building).
Updated description. Thanks for the info.
Can confirm in 23w03a
Can confirm in 1.21.
Diagonal blocks have been a way to force oak saplings to only grow as "fancy oak", i.e. (usually) large oak trees. I'm reasonably sure this behavior has existed for a long time, and currently a very intentional-looking check in the TreeFeature class. The thing that might not be intentional is that trees that generate with vines or other blocks, that are neither leaves nor logs, don't necessarily ignore those block types.