also known as Imbu-an or Tinglu
'Tinawon', coming from the regional language Ilokano and literally meaning 'once a year', is the broad linguistic term and common name used for this medium grain staple rice.
The specific variety of this nomination is called 'Imbuucan' in the Tawili language of the municipalities of Banaue and Hingyon, Ifugao Province. The municipality of Hingyon and the adjacent valleys that are located in the municipality of Banaue are the main production areas for the exported rice. The municipality of Hingyon was divided off from the municipality of Banaue in 1982, but historically, the people are of the same enthno-linguistic group.
Based on morphology, 'imbuucan' belongs to the rice genus and species Oryza sativa, subspecies tropical japonica (also known as javanica.) It is a slow growing staple variety that requires a 6-month growth period from transplanting to harvest. It is planted from December through February and harvested from the middle of June through August, depending on the elevation. The variety grows best in irrigated terraces and at an elevations of 700 meters above sea level. The plant is tall (115cm or 45 inches), cold tolerant, relatively non-shattering, very aromatic, and with medium tillering (10 tillers/hill).
Like the other Tinawon varieties, rats are attracted to the very aromatic Tinawon plant in the field. A single planting of Tinawon, or planting ahead or behind others in the community, will attract rats to that field. Because of this, all Tinawon must be planted in a synchronized method within the area.
The average length of the panicle is 41 cm (16 inches). It has an awn and the average number of grains per panicle is 172. The leaves are dark green and straight, pointing upwards. During the ripening stage, the terrace area planted with Imbuucan will have a reddish cast because of the peculiar red stripe of this grain that is not present in other Tinawon varieties grown in this area.
Imbuucan is a traditional native variety that has never undergone improvement in a formal breeding program or at research institutes. The indigenous women of the area are the primary holders of the traditional knowledge on seed selection and conservation of the best planting seeds.
Research on tropical japonica/javanica rice by the International Rice Research Institute (IRRI) states that this subspecies has been found in only three places in the world: remote areas of Indonesia, the rice terraces of the Philippines, and in the mountainous areas of Madagascar. Until recently, these treasured aromatic varieties were rarely sold into the commercial market.