Machaeranthera canescens: Hoary Tansyaster.
This Oracle native can grow over 3' high. Flowers are typically 1.5" wide
with narrow purple rays and a yellow center. This tall, multi-stemmed plant
has flowers at the end of each grayish, non-sticky stem. Blooms late
spring to mid fall. A butterfly magnet when massed, especially in dappled
shade. Perennial herb.