Leaf has an obtuse apex (no pointed tip, unlike R. ovata, though there may occasionally be a tiny tooth at the tip). Leaves ovate (egg-shaped, wider toward the base) ~2.5-6 cm long, 2-4 cm wide, glabrous (smooth-surfaced) or nearly so, medium to dark green on top and slightly lighter underneath, sclerophyllous and thick. Petiole (stalk connecting leaf to stem) is short (~2-4 mm), reddish. Margins are sometimes entire (smooth-edged) or sometimes with faint teeth especially toward the tip. Veining is pinnate, branching off the midrib, and the leaf sometimes looks "quilted" by the veins. Unlike R. ovata or Malosma laurina, the leaves are relatively flat. Flowers are small and fragrant, with 5 each petals, sepals, and stamens. The petals are white to rosy-pink, ~ 0.3 cm long, on dense, compact terminal panicles (compound flower clusters) with short reddish pedicels (stalks connecting flowers to central axis of the panicle). Flowers from February through May. Fruit is an oval, somewhat lemon-shaped drupe, sticky, pubescent, about 1 cm in diameter, tart/acid, and sweet. The fruit can be made into a lemonade-like beverage, hence the name, "lemonadeberry." It will sometimes hybridize with R. ovata, so it can sometimes be hard to sort out the continuum between them in certain areas where they overlap. Lemonadeberry forms a roundish shrub from 1-3 m in height, with many thick and twisting stems sprawling out along the ground to form some pretty large and impenetrable thickets. Young plants have reddish stems; as they age, the stems become scaly and greyish/brownish with the red showing through the scales. This shrub is the most common member of the Rhus genus on Palos Verdes Peninsula and stands out from the California sage scrub with its darker chaparral olive green color contrasting with the silvery and tan tones so common in CSS. Found in Southern and Baja California canyons in the Transverse and Peninsular ranges, mainly near the coast or in north-facing slopes farther from the coast.
Rhus integrifolia (Anacardiaceae): lemonadeberry or lemonade sumac
The development of this key was partially funded through the Geoscience Diversity Enhancement Program (Award #0703798) and through a course of re-assigned time provided by the CSULB Scholarly and Creative Activities Committee. Thanks also to the students in sections of biogeography, introductory physical geography, GDEP, and LSAMP for "test-driving" various editions of this key.