Walnuts

Rootstocks Available:

Northern California Black (NCB) Seedling

Paradox Hybrid (NCB X Persian Walnut) Seedling

The Walnut Index at U.C. Davis in the Fruit & Nut Research Center

Ashley

From the breeding programme of the Pomology Department University of California at Davis, 90% of lateral buds produce female ('pistillate') flowers, and therefore, potentially, nuts. Ashley matures it's nuts relatively early because it comes into leaf early. For this reason, it is not suitable for areas with heavy spring frosts. Like many early leafing Californian selections, it is extremely sensitive to being infected with walnut blight (Xanthomonas juglandii) if it is rainy in spring and therefore not so suitable for humid areas. The kernel weight averages 5.3 grams, and the crackout averages 50%.

Chandler

Midseason harvest; large, smooth, oval nut with good shell seal and very high quality kernel; excellent kernel color - consistently 90% + light grade; late leafing and bloom reduces frost, blight and codling moth susceptibility compared to earlier varieties; 80-90% lateral pistillate bloom; smaller size tree and lateral pistillate bloom suitable for high density plantings; precocious, medium to small size, highly productive, semi-upright tree; pollenized by Cisco and Franquette. (Patent # 4388)

Chico

Early harvest; small, upright, highly productive tree; small size nut with excellent kernel quality; often planted as a pollenizer for Vina but well-suited as a primary variety in high density plantings due to smaller size tree and very high percentage of lateral pistillate bloom (90-100%); needs an early catkin blooming pollenizer such as Sunland, Serr or Payne

Cisco

Extremely late-leafing variety with 80% lateral bud fruitfulness; large nuts with mediocre kernel quality--60% light kernels; yield potential may be limited; planted primarily as a Chandler pollenizer due to its precocious catkin production.

Forde

(UC95-26-37) is precocious with a harvest date 5 to 10 days before Chandler. Forde leafs out about 5 days before Chandler and is protogynous, 100% laterally fruitful and has a low blight score. The nuts are oval to round and medium textured with good seal and shell strength. The large kernels (9 gram) are light and extra light and make up about 54% of the total nut weight. Forde is intermediate in vigor between Sexton and Gillet. A potential pollenizer is Sexton. Patent Pending

Franquette

(Scharsch strain) Late harvest; small well-sealed nut with very good quality, light kernel; 0% lateral pistillate bloom - all nuts form on terminal buds; very large, upright tree is slow to come into bearing; considered one of the best pollenizers for midseason to late blooming varieties although its slowness to come into catkin production may limit its ability to pollenize young, precocious Chandler trees.

Gillet

(UC95-22-26) - has high yields on young trees and a harvest date 10 days before Chandler. Gillet is protogynous, 100% laterally fruitful and has a very low blight score. The nuts are somewhat more oblong than Sexton but are similar with good seals and strength, easy to remove light colored kernels and an 8.2 gram nut which makes up over 50% of the nut weight. Gillet is the most vigorous of the three new varieties. A potential pollenizer is Sexton. Patent Pending

Hartley

Midseason harvest; large, well-sealed nut with high percentage of light kernels; most widely planted walnut in California, a premium in-shell variety; late bloom and leafing minimizes susceptibility to codling moth and blight; low (5%) percentage of lateral pistillate bloom; large, productive tree is susceptible to deep bark canker and slow to come into bearing; usually planted with Franquette as a pollenizer.

Howard

(Patent # 4405) Midseason harvest; large, round, smooth and well-sealed nut with very high percentage of light kernels (90%); potential for less blight and codling moth susceptibility due to late leafing and bloom; 80-90% lateral pistillate bloom; good candidate for high density planting due to small to medium-sized, semi-upright tree that is smaller than Chandler or Vina; pollenized by Cisco or Franquette.

Livermore Red

Late season harvest, medium sized, vivid red kernels suitable for a specialty market. Lateral fruiting habit, moderate to heavy cropping; leafing occurs in mid-April. Patent Pending.

Payne

Early harvest; medium to small, very well-sealed nut; approx. 50% light kernels; very susceptible to blight and codling moth due to early leafing and bloom; 80-90% lateral pistillate bloom; very productive, medium-sized, round-shaped tree needs good pruning program to prevent overbearing in young trees and maintain vigor in older trees; pollenized by Chico but self-fruitful due to good coincidence of pistillate bloom and pollen shedding

Sexton

(UC90-31-10) - Precocious, harvests a week before Chandler and leafs-out a week before Chandler. Sexton has low blight scores and is 100% fruitful on laterals with abundant male and female flowers. Sexton is protandrous but the male overlaps most of the pistillate bloom. The nuts are relatively smooth and round with good seals and good strength. The kernels are light colored, easy to remove from the shell and at 8 grams make up more than 50% of the nut weight. Sexton has a densely branching canopy and will require substantial training and pruning of young trees to prevent overbearing. Potential pollenizers are Tulare and Chandler.

Serr

Harvest is early to mid-season. Nut size is large, with a fair to good shell seal. Kernel is 60% light. Percentage of kernel is high at 59%. Serr planted on shallower, heavier, or less fertile soil seems to bear better. Serr tree size is large and requires a spacing of at least 40 feet. Shape is moderately spreading and vigor is good to excessive. Suitable pollinizers include Chico and Tehama.

Sunland

An early leafing Californian cultivar carrying good crops of large nuts. Like many early leafing Californian selections, it is extremely sensitive to being infected with walnut blight if it is rainy in spring, and therefore not so suitable for humid areas. A good lateral bearer, 80% of lateral buds bear female flowers. Sunland has particularly big nuts, with kernels weighing 9.9 grams. Crackout is very good, at 58%. The nuts mature late. USA.

Tulare

Midseason harvest; large, nearly round, well-sealed nut; 75-85% light kernels; midseason leafing; average of 78% lateral pistallate bloom; very productive, precocious, moderately vigorous, upright tree is suitable for hedgerow and other high-density systems; good coincidence of pistillate bloom and pollen shedding. (Patent # 8268)

Vina

Early to midseason harvest; medium-sized, pointed nut with good shell seal; 60% light kernels; 80-90% lateral pistillate bloom; midseason bloom is moderately susceptible to blight and codling moth; medium-sized, round-shaped tree is moderately vigorous and highly productive; pollenized by Chico, Chandler, Howard or Tehama.

Note:
"% lateral pistillate bloom" refers to the percentage of fruit buds which are borne on the sides of branches rather than on terminal buds. Varieties with a high percentage of lateral pistillate bloom are more precocious and are considered better adapted to higher density planting, terminal fruit buds can be pruned off without removing entire crop.