Failure to learn plant properties fully at the maximum skill level

[PALU]

I've got a fairly recent (½ a year or so) Islander character who's managed to gain a 100 skill in Herblore, but still fails to fully identify Bog Beans.
When I reached 100 I reasoned that it might be a matter of reaching 100 on a check for a different plant after having checked the Bog Bean leaves, so I continued trying to identify it, and eventually "increased" the Herblore skill (a + sign by the still (of course) 100 Herblore skill, but still no full identification. I then went on to only test on the Bog Beans, and just reached a new level "increase", but I still get "There is still more to learn." at the bottom of the description.

It can be noted that there are descriptions for eating it and applying it topically, so it might be either a case of a complete description that somehow gets incorrectly described as incomplete, or a case of a the maximum skill roll still somehow failing consistently.

I believe earlier characters have been able to identify it fully, although Bog Beans are somewhat uncommon, so some characters may not have encountered it (or possibly have had it fully identified due to the cultural background).

Edit:
New character (7 strong wolf pack invading homestead vicinity ended previous one) reaching 100 in Herblore and fails to identify Yarrow completely (or at least the screen states there's more to learn). However, bog beans are claimed to be identified completely for this character (a Kaumolainen this time).

This character hasn't yet "increased" the skill while at 100. I'll continue until it does using Yarrow only. I don't expect it to change the situation, though.