Parkinsonia (syn. Cercidium) is a genus of about 12 species of in the family Fabaceae, native to semi-desert regions of Africa and the Americas.
They are large shrubs or small trees growing to 5-12 m tall, dry season deciduous, with sparse, open, thorny crowns and green bark. The leaves are pinnate, sometimes bipinnate, with numerous small leaflets; they are only borne for a relatively short time after rains, with much of the photosynthesis carried out by the green twigs and branches. The flowers are symmetrical or nearly so, with five yellow or white petals. The fruit is a pod containing several seeds.
Several of the American species have the common name "Palo Verde", which is Spanish for "green stick", in reference to the green photosynthetic bark.
- Parkinsonia africana. Southern Africa (Botswana, Namibia, South Africa).
- Parkinsonia anacantha. Kenya.
- Parkinsonia raimondoi. Somalia.
- Parkinsonia scioana. Eastern Africa (Djibouti, Ethiopia, Somalia, Kenya). Americas
- Parkinsonia aculeata (Mexican Palo Verde). Texas and Arizona south to Argentina; Galapagos Islands.
- Parkinsonia carterae. Western Mexico south to Ecuador.
- Parkinsonia florida (Blue Palo Verde; syn. Cercidium floridum). Southern California, Arizona, northwestern Mexico.
- Parkinsonia microphylla (Foothill Palo Verde; syn. Cercidium microphyllum). Southern California, Arizona, northwestern Mexico.
- Parkinsonia praecox. (Brea or Verde olivo; syn. Cercidium praecox). Mexico south to Argentina.
- Parkinsonia texana (Texas Palo Verde; syn. Cercidium texanum). Texas, northeastern Mexico.
Most American species are known by the common name of palo verde or paloverde, from the Spanish for "green pole" or "green stick". This name is derived from its characteristic green trunk.