How to best identify widely hybridized plant populations

Wondering if anyone else has input on this - in California we have a few groups of invasive plants that are descended from multiple invasive origin species and have been hybridizing with each other to the point it seems silly to try to identify them as any of the “parent” species at this point.

The prime example I’m thinking of is Carpobrotus -

The genus Carpobrotus in California resembles a large hybrid swarm, with putative hybrids forming a large portion of the overall population and tending to vary toward C. edulis.

The problem is, they’re getting identified pretty much at random as C edulus, C chilensis (usually based just on flower color) or, lately, any one of about 4 other Carpobrotus species which may or may not even occur in the state, and almost certainly do not exist in their pure form if they are here.

I’m tempted to just knock them back to genus when I see them with a note about hybridization, but I’m not sure that’s the best action, and also there’s over 10k observations at this point so it might take a while.

Another one is Raphanus raphanistrum/sativus, which I’ve just realized have actually been merged according to POWO, but for some reason there’s a deviation in place in iNat still, so the question of how to ID the hybrids remains until if/when that changes.

‘Hybrid swarm’ explains why it is so invasive for you in California.

Personally I don’t identity them. Not very helpful, I know! Carpobrotus and 90% of Opuntia I just hit “next”.

I ID them as C. edulis (cream flowers), chilensis (tiny pink flowers, rare here but common on the islands), and cf. acaciniformis (pink flowers).

Raphanus I judge by the population overall. If there is any yellow involved (yellow flowers or pink+yellow = peachy flowers) it’s raphanus x sativus. Pure pink and white is R. sativus. White and yellow is R. raphanistrum. The fruit are also useful. But there is certainly a large ambiguous area. R. sativus was originally a cultivar of raphanistrum I believe…

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