94,129
edits
Changes
no edit summary
|usda_ref=Flora - A Gardener's Encyclopedia ISBN 0881925381
|usda_ref=Flora - A Gardener's Encyclopedia ISBN 0881925381
|max_zone=9
|max_zone=9
|image=Upload.png
|image=Juglans ailantifolia.jpg
|image_width=240
|image_width=200
|image_caption=Japanese Walnut foliage and nuts
}}
}}
The '''Japanese Walnut''' (''Juglans ailantifolia''; synonyms ''J. cordiformis'' and ''J. sieboldiana''), is a species of [[walnut]] native to [[Japan]] and [[Sakhalin]]. It is a [[deciduous]] [[tree]] growing to 20 m tall, rarely 30 m, and 40-80 cm stem diameter, with light grey [[bark]]. The [[leaf|leaves]] are pinnate, 50-90 cm long, with 11-17 leaflets, each leaflet 7-16 cm long and 3-5 cm broad. The whole leaf is downy-pubescent, and a somewhat brighter, yellower green than many other tree leaves. The [[flower]]s are inconspicuous yellow-green [[catkin]]s produced in spring at the same time as the new leaves appear. The [[fruit]] is a [[nut (fruit)|nut]], produced in bunches of 4-10 together; the nut is spherical, 3-5 cm long and broad, surrounded by a green husk before maturity in mid autumn.
The very bold, decorative leaves make it an excellent [[ornamental plant|ornamental tree]] for planting in [[park]]s and large [[garden]]s.
Unlike the closely related and very similar [[North America]]n [[Butternut (tree)|Butternut]], Japanese Walnut is resistant to the [[canker]] [[disease]] caused by the [[fungus]] ''[[Butternut canker|Sirococcus clavigignenti-juglandacearum]]''. This has led to its being planted as a replacement for Butternuts in North America. The two species [[Hybrid (biology)|hybridise]] readily; the resulting hybrid ''Juglans x bixbyi'' is also resistant to canker and is likewise planted as a replacement for Butternuts. Japanese Walnut is distinguished from Butternut by its larger leaves and round (not oval) nuts.
==Cultivation==
==Cultivation==
===Pests and diseases===
===Pests and diseases===
The only significant disease Japanese Walnuts are susceptible to is the Walnut Bunch Disease.
==Varieties==
==Varieties==
The '''Heartnut''' is a [[cultivar]] of Japanese Walnut distinguished by its fruit, which is heart-shaped in cross section, easier to crack, and able to yield an unbroken nut meat when cracked. The Heartnut is a sweet nut without a bitter aftertaste often intrinsic with Black and Persian Walnuts.
==Gallery==
==Gallery==