Bajar Groves are a species of extremely poisonous, flowering flora utilized by the Space Pirates as a biological weapon, although whether they were naturally as dangerous as they were or if they were genetically modified by the Space Pirates like they do with so many other species. Their homeworld is unknown, but it is certainly possible that they evolved on Utragia, especially given the Space Pirates' extreme resistances to poisonous substances such as the Blueroot Trees that may also originate from their homeworld.
They are apparently an alkaloid species, as not only did Mother Brain mention that the Space Pirates were detected due to this chemical but also that the Iona Faria showed traces of it as well once they were corrupted; if this is true as well as their being from the homeworld of the Pirates, then the Pirates themselves would likely be an alkaloid species.
The Bajar Grove were utilized against the planet Zebes when the Space Pirates first attacked it. The Chozo took drastic actions to destroy the flora, burning the entire valley that they had been dropped into. This lends credence to the concept that they may poison and corrupt the surrounding land as well as the lifeforms that they do, such as the Iona Faria whom had attempted to pollinate the "plants". The corruption that occurs seems to turn an organism into an ally of the Space Pirates, causing them to attack others not aligned with their new masters.
It can be assumed that the Bajar Grove is the first weapon dropped onto worlds at the beginning of a Space Pirate invasion, although there is no known examples of this having occurred on K2-L.
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