What are the excellent foreign walnut varieties?

  1. Payne

  Origin and distribution: native to the United States. Currently, its cultivation area in California, United States is second only to Hartley. It belongs to the late-bearing walnut variety type.

  Fruit economic traits: nuts medium to small, average single nut weight 11.25 grams. Suture tight, kernel-out rate 48%, light-colored kernels account for about 50%.

  Growth and fruiting habits: tree medium-sized, crown round, growth vigor strong. High-yielding, lateral mixed bud rate reaches 80%-90%. To prevent excessive fruiting, young trees need moderate or heavy pruning, and mature trees also need appropriately heavy pruning to maintain tree growth vigor. Early-maturing variety. In California, United States, leaves unfold in mid-to-late March, flowering occurs in mid-to-late April, and the female and male flowering periods coincide, so a relatively high yield can also be obtained when planted as a single variety; it matures in early September. However, it is susceptible to damage by codling moth and bacterial black spot. Suitable for sparse planting with a medium crown.

  2. Vina

  Origin and distribution: native to the United States; a main cultivar in the United States, introduced into China in 1984. It belongs to the early-bearing walnut variety type.

  Fruit economic traits: nuts conical, base flat, tip tapering, nut weight 11 grams. Shell thickness 1.4 mm, smooth. Suture slightly wide and flat, tightly closed. Kernels easy to remove, kernel-out rate 50%.

  Growth and fruiting habits: tree medium-sized, tree vigor strong, tree posture relatively upright. Lateral mixed bud rate above 80%, early-bearing type variety. Protandrous type, medium-maturing variety. This variety is suitable for the climate of the North China walnut cultivation region, and its cold resistance is stronger than that of other American cultivars. Strong early high-yielding ability.

  3. Franquette

  Origin and distribution: native to France. It has been widely introduced and cultivated in walnut-producing regions of Europe and America. It belongs to the late-bearing walnut variety type.

  Fruit economic traits: nuts medium, average single nut weight 11.09 grams. Suture tight. Kernel-out rate 46%, kernel color extremely light.

  Growth and fruiting habits: tree tall, strongly upright, growth vigor medium to vigorous. Generally only terminal buds can set fruit, relatively high-yielding. Late-maturing variety, maturing in late September in California, United States. The greatest characteristic of this variety is that spring budbreak and flowering are relatively late, so it can avoid damage from late frost. Suitable for sparse planting with a large crown.

  4. Chico. Origin and distribution: native to the United States, a hybrid progeny of Sharkey X Mar-chetti, and a very good early-bearing type variety.

  Fruit economic traits: nuts medium, average single nut weight 10.64 grams. Suture tight. Kernel-out rate 47%, 70% are light-colored kernels, and kernel quality is extremely excellent.

  Growth and fruiting habits: tree small, crown round, upright. Strong high-yielding ability, lateral bud fruiting rate reaches 90%-100%. In California, United States, leaves unfold in mid-to-late March, flowering occurs from late April to early May, protogynous variety. This variety has a small, upright crown and is suitable for close planting (hedgerow) cultivation.