Mesquite & Prosopis
Shrub or multi-stemmed tree, occasionally single-stemmed, with sturdy spines. Often confused with Acacia, but it has straight spines rather than thorns. Leaves twice-compound, with few pinnae pairs (1-2, sometimes 3). Flowers yellow, in fluffy spikes carried near branch tips. Fruit long, cylindrical or flattened pods with raised bumps over the seeds, often beaked.
Widespread in Namibia, although often localised. Highly invasive in dry river beds, especially in the south-east, out-competing local trees and extremely water-hungry. The pods are nutritious fodder, while the wood burns well, and the sawdust is excellent for smoking fish and meat. These species produce masses of pollen in spring, to which many people are dangerously allergic. The City of Windhoek has a by-law that prohibits the planting of any of these species.
There are at least three species in Namibia, Prosopis glandulosa, P. velutina and P. chilensis, the most common of which is P. glandulosa. These species hybridise freely, so they may be difficult to identify (see table below). For this reason we will record them as a single species for the purpose of this atlas.
Common name: Honey mesquite (English); ‡khòńhai.s (Khoekheogowab); |nàra.s (Damara); !khàa.s (Nama)
Origin: Southwestern United States and Mexico
Common name: Velvet mesquite (English)
Origin: United States and Mexico
Common name: Chilean Prosopis (English)
Origin: South America
Characteristics of Prosopis glandulosa, P. velutina and P. chilensis
|Prosopis species||Thorns||Foliage texture||Number of pinnae pairs||Pinnae length (cm)||Leaflet pairs per pinna||Leaflet length and width (mm)||Leaflet distance apart||Leaflet shape||Inflorescence length (cm)||Pod shape and colour when ripe||Pod length and width (cm)||Number of seeds per pod|
|glandulosa||1-4.5 cm long, sometimes single.||Smooth||1 or 2||6-17||6-17||20-63 x 1.5-4.5||Distant, 7-18mm apart||Linear or oblong||5-14 cm||Almost straight, sometimes slightly curved, Straw-yellow or tinged violet||8-20 x 0.7-1.3||5-18|
|velutina||1-2 cm long.||Finely hairy||1 or 2, sometimes 3||2-9||12-30||4-13 x 2.0-4.0||adjacent||obtuse||5-15 cm||Straight or slightly curved. Yellow, sometimes reddish||8-16 x 0.6-1.0||10-17|
|chilensis||Sometimes thornless, often with few thorns. Thorns conical, up to 6 cm long.||Smooth, rarely finely fringed||1 or 2, sometimes 3||8-24.5||10-29||11-54 x 1.1-3.0||Distant, 4-12mm apart||Long-linear||7-12 cm||Straight or curved, sometimes very curved. Straw-yellow||12-18 x 1.0-1.8||20-32|
Hover over each photo to see which species it is.
Photos of P. velutina: S. Baskauf http://bioimages.vanderbilt.edu