With decreased residential lot sizes, the popularity of small patios and entry courtyard and increased demand for open space in commercial and multi-family complexes there is an emerging demand for small stature desert adapted landscape trees. It is unlikely that many landscape professionals are familiar with Kidneywood trees, yet two Eysenhardtia species, E. texana (Texas Kidneywood) and E. orthocarpa (Kidneywood) are ideal for sites that demand smaller trees. Both species are relative cold hardy, (15 degrees for E. texana and 15 to 20 degrees for E. orthocarpa) and are well adapted to desert conditions. They are both native to the desert southwest, with E. texana found in northeastern Mexico to central Texas and E. orthocarpa native to Sinaloa, Mexico to southeastern Arizona and southwestern New Mexico.

They are described as semi-evergreen under some Arizona conditions, retaining a portion of the foliage in all but the coldest winters. The leaves are finely divided, similar to Sweet Acacia but the leaflets are larger, with anywhere from 20 to 40 leaflets per leaf. With these species both leaves and flowers are fragrant (probably explaining one of the common names for E. orthocarpa of Palo Dulce meaning sweet stick in Spanish). Both species exhibit a moderate growth rate in landscape settings with irrigation and fertilization.

Kidneywood (E. orthocarpa) grows naturally in water courses, canyon slopes and hillsides where summer water is periodically available. Its natural distribution is limited by summer rainfall patterns and relatively mild winter temperatures. It is both cold temperature and drought deciduous but in mild winters or protected microclimates retains its foliage through the winter. It grows naturally as multiple slender branches with no thorns. Depending on available water, trees reach heights ranging from 10 to 20 feet tall with 6 to 12 foot spread. Trees planted in landscape setting with regular irrigation will tend to mature toward the upper end of this range. Flowers appear sporadically from April to September, typically in response to winter and summer rains. These fragrant, white flowers are arranged, at the branch terminal, in a long slender, spike-like raceme 2 to 3 inches long. Pods containing one seed each are produced from the flowers. Mature pods detach from the tree easily.

Texas Kidneywood (E. texana) matures to a height of 6 to 12 feet with spreads of 6 to 9 feet in irrigated plantings. This specie also has no thorns. Flowers are produced in abundance with adequate irrigation. White, 3 to 4 inch flower spikes are found at branch terminals from April to November. Trees will shed leaves when drought stressed but rapidly re-leaf when water is available. The tree has been naturalized in some, but not all, landscape settings.