Extra cold hardy cultivars of Morus nigra
I am looking for extra cold hardy cultivars of Morus nigra. I live in an area which is on the borderline for Morus nigra to survive. The temperatures can, however seldom, reach down to -23°C for short periods.
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Old French walnut type
I ask your opinion and advice regarding an old French walnut type.
English publications on walnut growing from the 1880's to the 1950's often mention a type of natural dwarf walnut that only forms a bush or small tree. It appears not to be a cultivar as such but more a type... probably often raised from seed. It's usually called 'Dwarf Prolific', 'Noyer Fertile' or 'Praeparturiens'.
It used to be in the walnut collection at the East Malling Research Station, Kent, but they tell me all their walnuts were grubbed out years ago. I've made several attempts to contact the relevant French authorities but have had no success there either.
Do you recognise anything that resembles the following description, from "'Walnut Varieties" in the Annual Report of East Malling Research Station, 1950/51?
"Fertilis : Juglans regia fertilis or praeparturiens is usually recognised as a sub-species of J. regia. It is said to form a small tree or bush, bearing clusters of nuts, and cropping at an early age. The clonal selection P20 (the one East Malling grew) appears to have many of the characteristics of this sub-species.
Tree : Small and compact, with a fairly dense round head. Leafs out in early April, too early to escape spring frosts except in comparatively frost free situations. The young shoots are very red in spring.
Leaves : Light green, medium to large, with a short rachis. The leaflets are oblong, flat, with a fairly large terminal leaflet, and often only two pairs of lateral leaflets. The tufts of glandular hairs on the under surface are conspicuous.
Flowers : Protandrous. The dormant catkins are of medium size, broad and pointed. When shedding pollen they are of medium size and broad. This variety bears numerous catkins, but the majority are often killed by frost. The pistillate flowers are very numerous, borne in clusters.
Nuts : Small, round, or slightly conical. Shell thin, well sealed, well formed even in wet seasons, pale in colour, smooth, of attractive appearance in spite of its small size. Nuts very well filled, flavour very good. Good for pickling or dessert. Nuts borne in clusters. The green husk is downy or hairy, even when the nut is ripe. A heavy cropper, except when killed back by spring frosts."
As you might guess it's a very poor walnut for the UK, being too susceptible to frost damage. However, I think it would be interesting to use it as a starting point to try breed something similar but much later vegetating. There would be a lot of interest from UK amateurs for a 'dwarf' walnut tree that would fit into the modern small garden.
If you know of any old French walnut that fits this description I'd be very interested to hear about it!
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Extra härdiga varieteter av Morus nigra
Jag är intresserad av extra härdiga varieteter av Morus nigra som kan klara kyla ner till ungefär –23C.
Jag bor i ett område som är på gränsen för att M. nigra skall klara sig under en längre tid.
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