Note: It is curious that a denomination named for one grape variety (Trebbiano) allows the possibility of making a varietal wine from a different grape (Bombino Bianco). The reason for this anomaly is that the two varieties, which may or may not be related, have frequently been misidentified for one another and/or thought to be interchangeable. Consequently, many growers have both varieties planted in their Trebbiano vineyards. There are only 12 hectares of declared Bombino Bianco vineyards in Abruzzo, compared with over 9,000 hectares of declared Trebbiano vineyards. The disciplinare simply acknowledges this state of affairs.