Some trees generate with leaves too far from logs

I've notice this happening occasionally too. Especially in jungles. At first I thought it was a feature until I read it under the bugs section on the minecraft wiki.. I kind of like it actually. Shouldn't trees dropp saplings and apples naturally anyway? That's my opinion at least.

I have the same thing happen. Not only in creative, in survival as well. Happens pretty often in jungles and in forests.

This basically makes jungles unplayable for me, trying to build a treefort just results in balding trees

Sean: Uh, not exaggerating at all there? At least for me, the leaves that will decay will do it soon enough, and the amount of leaves lost is insignificant. I merely consider it a free source of saplings and an occasional apple.

Say, move to the area, start building temporary work base (platform, walls, roof, some chest, work stuff, unload crap from inventory). Leave Steve (safely) idling there for a cup of coffee/tea/healthy walk around the block. Come back, no more leaves decaying, so start working. Still more than 90% of original leaves left, way too much for my liking.

Not saying there is no related bug(s), but it certainly does not make jungles unplayable.

If, somehow, the jungle is getting almost completely stripped from leaves, there is some other problem going on, and very very likely not part of vanilla code.

Is this still a concern in the current Minecraft version 1.6.4 / Launcher version 1.2.5 ? If so, please update the affected versions in order to best aid Mojang ensuring bugs are still valid in the latest releases/pre-releases.

Test with large jungle trees: Leaves have the meta data part "check_decay" (+8) that is only true when the block touches a log block or a block next to it receives a block update. Then it checks if it should decay. From my tests just a block update does nothing, so it apparently only checks for decay if the block update was a leave decaying or a log being removed. That means that it's fixed for 1.10.2. Correct?

Assuming this is referring to the same effect, can confirm for 1.10.2. Steps to reproduce:

1) Generate a jungle giant tree, either naturally or from saplings and bonemeal.
2) Place a wood block at the edge of the canopy leaves.
3) Remove the wood block.
4) Wait a few minutes.

The canopy leaves will rapidly decay from the original round shape to a smaller diamond-shaped configuration. I've attached before-and-after pictures of a naturally-generated tree to which I've done the above steps.

EDIT: Fire (such as from lightning) will do the same thing, as will manually breaking a leaf block. Other types of block updates don't seem to have any effect, as Fabian pointed out above.

It appears to be due to the decay rules for leaf blocks. They decay if they aren't connected within 4 blocks of a wood block, but jungle giants naturally generate with canopies larger than that. Hence, they remain in a sort of natural BUD state until they receive a suitable block update that triggers them to decay. Large oak trees are also be subject to this effect, but it's less noticeable due to their irregular shape.

A simple workaround could be to modify jungle giants to generate with wood block "branches" embedded in their canopies. Otherwise, I don't know... Have separate decay rules for jungle leaves?

I looked more into Fabian's comment above... I guess the problem is "fixed" in that these leaves don't spontaneously decay on world generation, if that's what the original bug report is describing. But the root problem remains, and the leaves will still decay if they receive a leaf-related update.

I'm not entirely sure what "check_decay" is supposed to do? I'm seeing leaves decay with "check_decay" set to False, so it seems to have no effect on whether or not a particular block decays on receiving a block tick.

Also affects 18w10d.

Fixed for 18w22a: From what I have heard, the radius that leaves can survive near a log has been increased to 6.