After several weeks of summer monsoon rains, the grass grows tall and lush in the upland areas around Tucson, especially to the south and east. I don't much like walking through the tall, green grass in the late summer and early fall for fear of snakes and chiggers (my ankles are proof that we do get chiggers in southern Arizona at this time of year), but I spray myself with DEET and do it anyway because some of our most interesting wildflowers like Harlequinbush (Gaura hexandra) can be found there.
Harlequinbush is in the Evening Primrose family (Onagraceae), and unlike the other members of this family with their characteristic four-petaled flowers, the flowers of Harlequinbush are often trimerous (having flower parts in sets of three). Harlequinbush flowers are on tall, slender stalks and have 3 or 4 bright pink, twisted petals and 3 or 4 pinkish, reflexed sepals.
Despite their bright pink flowers, Harlequinbushes can be fairly inconspicuous amidst the tall grass, but they are actually quite common in these grassy upland areas.