Custom leaves not decaying as they should

I've been fiddling and fiddling with this for almost a week now, constantly looking up answers but to no avail.

My custom logs are inside the correct tag: logs>Minecraft>Blocks

and my leaves are even inside a tag: leaves>Minecraft>Blocks

The leaves materials is set to Leaves and the base block is set to Leaves. From what few search results I was able to find, that alone should be enough to get them to behave like vanilla leaves, but they simply refuse to decay with or without logs nearby.

I'm out of answers at this point so I've come here to request help.