New Walnut Variety Released

By Growing Produce Staff|April 10, 2013

The University of California (UC)-Davis Walnut Breeding Program has recently released a new walnut variety, Solano. According to the program’s Chuck Leslie in the Department of Plant Sciences, this variety harvests early-mid season with light colored kernels, high yield, large nuts, and solid attractive shells.

Solano has leafing, flowering, and harvest dates that are very similar to Vina, but Solano has better kernel color and tree structure and should be of particular interest to growers in the Sacramento Valley. It produces large, uniform, oval-shaped nuts with good appearance, solid seals and shells, and easy removal of halves. Nuts average 14.6 grams with 8.0 gram kernels and 55% kernel weight. The kernels have very good color, averaging 93% light and extra light and 54.8 RLI in trials. The shell and seal strength is clearly sufficient for use as an in-shell nut if desired.

Solano is precocious, 100% laterally fruitful, and has exhibited excellent yields in campus and grower trials. Known as selection UC95-011-16 prior to its release, Solano originated as a seedling from a 1995 cross of Tulare sibling UC67-13, used for quality, and the variety Chico, used for yield. It has been evaluated as a selection in regional blocks in Butte, Yolo, and Fresno Counties and in grower trials in Tehama, Butte, Sutter, and Yolo counties. Grower feedback has been very positive.

Solano leafs out a week later than Payne, Serr, or Ashley with a protandrous bloom habit (the catkins shed before the female bloom). It harvests ahead of Tulare or Howard and more than two weeks before Chandler. Solano’s timing is similar to Vina but has a more easily managed canopy, better kernel quality, and larger nuts. Canopy structure in grower trials has been upright and without evidence of limb breakage to date. Tree size at maturity is expected to be similar to Chandler and overlapping pollen sources include Tulare, Chandler, and Howard.

Due to its later leafing date and male-first bloom habit, this variety will have less exposure to spring rain than another recently released variety, Ivanhoe, and is therefore anticipated to be less susceptible to blight and more suitable for planting in the Sacramento Valley. Solano is now commercially available and can be ordered from any licensed nursery.