BurseraceaeFrankincense family

  - Leaves alternate, odd-pinnate (rarely mixed with trifoliolate).
  - Leaflets opposite and entire.
  - Without stipules.
  - Turpentine odor.
  - Pealing orange and green bark (Bursera).
  - Petiolules swollen at base and tip (Protium).
  - Flowers small, 4-6-parted, in axillary inflorescences.
  - Fruit a capsule with arillate seeds.

Diagnosis: Trees; without stipules, aromatic odors like turpentine, clear or slightly milky latex that dries white, leaves alternate, odd-pinnate, entire, the rachis and petiole often reddish. Bursera has rust and green bark pealing in papery sheets; Protium has petioles swollen at boths ends and the terminal leaflet tipped up.

Local distribution: Pacific slope dry forest (Bursera) and Atlantic slope rain forest (Protium).

Similar families
Anacardiaceae: mango odor, latex drying black, fruit a drupe.
Meliaceae: sweet odor, no latex.
Rutaceae: translucent yellow dots, often spiny.
Simaroubaceae: bitter odor and taste, leaflets mostly alternate.

Diversity: Total: 2 genera, 5 species. Trees: 2 genera, 5 species.

Comments: Bursera commonly grows on rocky or riparian sites in San Luis and is also frequently used as a living fence post.

Credits: Images and text copyright 2000-2007, William A. Haber, http://efg.cs.umb.edu/