Citrus trifoliata

The trifoliate orange or Japanese bitter-orange, or Chinese bitter-orange is in the citrus or Rutaceae family and is native to China, Korea and Japan. It is a thorny, well-branched, deciduous shrub or small tree which typically grow up to 5 m tall. It is also known as Ponciris trifoliata.

It is particularly known for its large 3–5 cm thorns on the shoots.

• Leaves are deciduous, trifoliate (3 leaflets), with the central leaflet 3–5 cm long, and the two side leaflets 2–3 cm long; leaves emerge yellowish-green in spring, turning glossy dark green and fading to yellow in the fall.
• Flowers are white, fragrant, 4-7 petaled, 3–5 cm in diameter, with pinkish stamens, size larger than those of true citrus but otherwise closely resembling them, except that the scent is much less pronounced than with true citrus.
• Fruit is green, ripening to yellow, and 3–5 cm in diameter, the size of a lime, but resembling a small orange; it has a finely downy surface and a fuzzy texture similar to a peach. It has a smell distinct from other citrus varieties and ripens to an attractive yellow in the fall.