The Hartley walnut, exhibited in 1915 at the San Francisco World's Fair, won blue-ribbon recognition as a premium in-shell nut. Today, Hartley is the standard for mid late-season walnut harvest. Hartley is a consistent producer, despite being only slightly fruitful on lateral buds. The Hartley nut is fairly large with a pointed tip. Thin-shelled, well-sealed and easy to crack, Hartley produces a high percentage of light kernels (76%). The tree is medium-to-large, moderately spreading and has low susceptibility to codling moth and blight. When stressed by a lack of water or poor soil, Hartley is susceptible to deep bark canker. Hartley is usually planted with Franquette as a pollenizer.