▁It ▁is ▁most ▁likely ▁that ▁the ▁gra pe ▁is ▁native ▁to ▁the ▁Lo ire ▁Valley . ▁Most ▁of ▁the ▁gra pe ' s ▁vit icult ural ▁history ▁is ▁tied ▁into ▁the ▁historic ▁T ou raine ▁region ▁where ▁it ▁is ▁still ▁most ▁pre val ent ▁today , ▁particularly ▁in ▁the ▁Lo ir - et - Ch er ▁département . ▁The ▁gra pe ▁is ▁on ▁the ▁decl ine ▁in ▁plant ings ▁and ▁importance ▁though ▁it ▁is ▁still ▁a ▁permitted ▁gra pe ▁variety ▁in ▁several ▁A OC s ▁including ▁being ▁the ▁only ▁gra pe ▁other ▁than ▁Chen in ▁blanc ▁permitted ▁in ▁V ouv ray . ▁ ▁W ine ▁▁ ▁The ▁Ar bo is ▁gra pe v ine ▁is ▁highly ▁vig orous ▁and ▁pr one ▁to ▁producing ▁high ▁yields . ▁If ▁the ▁yields ▁are ▁not ▁kept ▁in ▁check , ▁the ▁white ▁w ines ▁produced ▁from ▁the ▁g rap es ▁can ▁be ▁less ▁ref ined ▁in ▁flav or . ▁Comp ared ▁to ▁the ▁Chen in ▁blanc ▁gra pe ▁that ▁is ▁found ▁throughout ▁the ▁Lo ire , ▁Ar bo is ▁tends ▁to ▁produce ▁so fter ▁w ines ▁with ▁less ▁notice able ▁acid ity . ▁For ▁this ▁reason , ▁Ar bo is ▁has ▁mostly ▁been ▁val ued ▁as ▁a ▁" soft ening " ▁agent ▁to ▁the ▁higher ▁acid ▁vari eties ▁of ▁Chen in ▁blanc , ▁Sav agn in ▁and ▁Rom or antin . ▁ ▁Syn onym s ▁Among ▁the ▁syn onym s ▁that ▁Ar bo is ▁is ▁known ▁under ▁throughout ▁France ▁are ▁Menu ▁P ine au ▁and ▁Pet it ▁P