North American Fruit Explorers mailing list at ibiblio

[Devin Smith <dvidedevo@yahoo.com>]

Hi all-I received a surprise delivery a couple of days ago-- mulberry 
cuttings that I had ordered from the GRIN germplasm database over a year ago! 
Several of the accessions I requested are listed as Morus macroura, which is 
what GRIN lists as the species of 'Pakistan' mulberry (others list as M. 
alba). I know that 'Pakistan' is very low chill and not terribly hardy (I'm 
in Vermont), but my interest was piqued by some of the other M. macroura 
offerings. Accession 'DMOR 9' for example, resembles 'Pakistan' in fruit form 
and size, and the description suggests it may be fully hardy in zone 5. 

https://npgsweb.ars-grin.gov/gringlobal/accessiondetail.aspx?id=1564196
Check out the narrative provided for this accession:
"Information from Seed Savers, page 375: Large, 1 inch [2.54cm], juicy, red 
to purplish black fruit similar to blackberries; can be quite delicious. 
Small, wide spreading, deciduous tree grows 20-30 feet [6.1-9.14m] tall. Very 
long-lived, becoming gnarled and picturesque. Similar to Russian Mulberry in 
that it can be used to make a fine hedge; very attractive to birds. Ripens in 
late spring. Hardy to at least -10 degrees Farenheit. Grows well in Zones 
5-6. Native to western Asia"

The only wrinkle I can see offhand is that it says the fruit is 1" (long I 
assume) while the pictures clearly show the fruit to be about 2.25" long. 
Maybe this is a simple mixup and the narrative is not relevant to this 
accession. Does anyone know more about Morus macroura-- its geographic 
distribution, hardiness, or any other relevant properties? 

My thought was to grow a couple of these macroura accessions with protection 
in the hopes of performing some crosses with hardy M. alba varieties to 
possibly produce some hardy large fruiting 'pakistan' types.

My only known pollen producer is 'contorted', which is also listed as both M. 
alba and another species, M. bombycis. Do superior fruiting types-- 
'Geraldi', 'Ill. Everbearing', 'Collier', etc. produce male flowers in 
anyone's experience? I see that GRIN lists "Geraldi Dwarf' as an M. alba x M. 
nigra, and I wondered immediately how they knew that and what the logistics 
might be of performing such a cross. I guess the M. nigra would likely have 
to be container grown and its flowering would have to be manipulated to occur 
at the same time as the M. alba growing outside. I recall reading about 
mechanical pollination of kiwis in New Zealand, and how they mix the pollen 
in a dilute liquid solution and spray that onto the flowers. I thought that 
was very odd and that it would spoil the pollen until I read more about types 
of pollen. Apparently wind pollinated plants, which are properly called 
anemophilous, have pollen with very different pollen which endures this type 
of treatment. Has anyone on the list played around with this? I thought 
something similar might work for paw paw's -- maybe using an atomizer and 
something inert like corn starch to dilute the pollen.