Nigra varieties are apparently not well suited to humid summer climates, and don't seem to be as cold hardy in the Northeast for example as they are for me in the Southwest.

Check out as many threads on the subject as possible… its seems IE is not a favorite everywhere, and both are not incredibly productive because the crop is so spread out.

Good luck

The former could be true, especially if mulberries like that scratched over bare earth that chickens leave behind. I rather doubt the latter is very useful, after observing a flock near an enormous mulberry tree last spring show absolutely no interest in eating any of the berries!

I was unaware of this potential confusion, though of course the White, Black, Red, has always thrown people off because they naturally think it refers to the fruit (when in fact it refers to the wood and/or bud color). All of these common names can get even more confusing from place to another as well.

As always, sticking to the Latin names is the safest bet. There is a named variety of Morus nigra (black mulberry) called "Persian" though, which is probably what RSilvulka is talking about.

I highly doubt the claim that any Morus rubra genes exist in varieties of Morus nigra, since the latter does not form seeds and must be propagated asexually. On it's own, Morus nigra is typically hardy to zone 7 or 6.

This is confusing to me. I mean you can't have a species that cannot reproduce sexually. No male trees? It was one tree that all come from? Some strange natural hybrid? Plus many Nigra exist, not just one.
You couldn't pollinate with rubra pollen? I thought lack of seed production was from being female with no males around. I guess I need to research this to see what I'm missing here. Looking at the ARS site they say it can form seeds and escapes into the wild from time to time.
I understand that a hybrid could be asexual like IE is a hybrid. The native trees around me must be purple rubra. The berries are very good.

What we call M. nigra is in fact believed to be an ancient hybrid. That there are many different cultivars of it does not refute the claim that it is seedless even with pollinators nearby since there could have been multiple hybridization events, as well as many new varieties from bud mutations over the thousands of years we are talking about (yes this is an ancient cultivated plant).

Several people have also said on this forum that most of the named cultivars of M. nigra are incredibly similar if not identical.

As far as seeds go, you're right there is mention of this plant forming seeds, but it seems to be the exception, and with all the confusion surrounding the genus it is possible that some of these plants are not M. nigra at all.

Hermitian:
As far as M. nigra hardiness is concerned, it seems to vary with the cultivar and the type of climate (humid or arid). My 'black beauty' has made it through -23 F without a problem (that's a zone 4 low) and every year sees at least 0 degrees. The only reasons I can think of as to why the research station found so little cold hardiness is because it sounds like they were dealing with cuttings instead of mature trees. Also, as with all mulberries, cold weather kills the branches very readily if the plant is not fully dormant.

DMOR 41 : Accession was donated by Todd Kennedy.

DMOR 92: Accession was collected. 05-Oct-2006. Armenia.
Locality: Syunik Province; roadside along Iran border. Waypoint 199. Latitude: 38 deg 55 min 4 sec N (38.91777778), Longitude: 46 deg 22 min 2 sec E (46.36722222). Elevation: 497 meters. Quantity: 3 ct Comment: Many with holes drilled in seed by arthropods? sorted to remove all with holes.

DMOR 116: Accession was collected. 15-Sep-2011. Korce, Albania.
Locality: Boboshtica Habitat: Several very old trees (>100 years). Latitude: 40 deg 33 min 24 sec N (40.55672), Longitude: 20 deg 45 min 57 sec E (20.76588). Elevation: 954 meters

DMOR 119: Accession was donated by Roy Wiersma and Steve Spangler.

DMOR 120: Accession was donated by Steve Spangler.

Thanks for the iinfo, makes sense now! Yeah old hybrids are pretty cool. I have Indian Free peach that is least 150 years old. No reason why they could not be centuries old. i want to get a black beauty for here in a few years after I move. It's a small tree too, whcih i like. I would like a few of the ornamental mulberries too. I like the looks, All are small, again i like that. Nigra may be the best tasting but the others are not bad. I like the wilds here which must be a form of rubra, all the same the taste is top rate. When i make jam my family says it's the best I make.

The bush/tree distinction with these really has to do with how it is grafted (and/or pruned I would assume). Mine are trees since they are grafted very high, about 4 feet above the ground, onto what I assume is Morus alba rootstock. But they are still quite small, my older one is still only about 8 feet tall by 5 feet wide after 4 years.
Every one I've seen of this shape has an awfully ugly graft union, but they don't seem to be harmed by it.

There are some low-grafted plants available, which hide the graft union better and branch very low so they look like bushes. These aren't as special in the landscape as the former, but they would be much easier to harvest from. A row of these things would be much more valuable than a row of blackberries in my opinion.

Another advantage of M. nigra that you might not have heard of is that birds won't bother the fruit nearly as much because the thick sandpapery foliage does such a good job at hiding the berries. This also makes them more difficult to harvest!

My only beef with M. nigra as I mentioned earlier in the thread is that it's long ripening season means that you never get a whole lot of berries at one time, and you have to pick every few days to take advantage of all the ripe ones.