Catclaw Acacia

Peanut, soybean, lima bean

Catclaw Acacia ( _Senegalia greggii_, formerly _Acacia greggii_) is one of the most common and ecologically important native shrubs in Arizona, found throughout the state from the low Sonoran Desert floor to grassland and chaparral slopes up to 4,600 feet. It grows in rocky canyons, desert washes, gravelly hillsides, and arroyo banks across every corner of the state, from the Phoenix metro area and Tucson basin through the Verde Valley, Mohave County, and the southeastern Arizona borderlands. Unlike some desert natives with limited native ranges, Catclaw is genuinely ubiquitous, and its hooked, cat-claw-shaped thorns make it one of the more memorable desert encounters for hikers and homeowners alike.

Its fragrant, creamy-white flowers appear in dense cylindrical clusters from April through October, one of the longest bloom seasons of any Arizona native shrub, with peak flowering in May and June and a secondary flush after monsoon rainfall in late summer. The flowers are primarily pollinated by bees, native insects, and butterflies, and the plant is an important honey source in Arizona, producing what is known as catclaw honey. Because it is insect-pollinated rather than wind-pollinated, its pollen is not dispersed in the high volumes associated with wind-pollinated allergens like olive or mulberry. However, pollen.com classifies the Acacia genus as producing “severe allergies,” and Catclaw’s long bloom window means sensitized individuals can face cumulative exposure throughout much of the year.

As a member of the Fabaceae family, Catclaw Acacia shares allergenic proteins with other legume plants. Cross-reactivity with mesquite pollen ( _Prosopis_ spp.) is biologically expected given their shared family and confirmed in studies on the broader Acacia–Prosopis allergenic relationship. The foliage and twigs also contain a cyanogenic glycoside (prunasin), which is mildly toxic to livestock and humans in large quantities, though this poses no practical allergy concern for typical landscape exposure.

In the landscape, Catclaw is valued for its screening density, wildlife habitat, and the seasonal display of its flowers. Its deep root system, recorded to depths of more than 18 feet in southeastern Arizona, makes it highly drought tolerant and useful for erosion control. Given its thorns, it should be planted away from pedestrian areas.