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>   c.. At what price are the rootstock plants sold by the nurseries in the US and other countries.

 

Retail: Very few outlets, but about $3.50 (less for larger quantities down to $1.75 for 25 or more). 

Wholesale would probably be much cheaper.

 

There are different groups of apple rootstocks:

Best known:

MM, M, and EMLA.  Example, one variety of well known dwarfing stock in this line is known as

EMLA 26.  The others have different numbers (the numbers have nothing to do with their size).  They

are the 'original' size controlling stocks.  Some were later found to be virussed and the reissued, de-

virussed forms are denoted by EMLA.  Each has known strengths and weaknesses.

 

Budagovsky(Bud) 9 (out of Russia) - Dwarfing but hardier than its 'about' equivalent EMLA 26.  It also is

more tolerant of wetter so

 

There was a P numbers selection out of Poland - haven't heard anything about it lately,  There

was also a selection out of Canada whose letter designation escapes me, but though it was a good

rootstock but the finished tree often went into shock (and died) when the finished tree was transplanted

(I personally experienced this.).  So to be successful with it you'd have to transplant the stock to the

field in their permanent locations and then field graft the scions on.

 

The above (I believe) are all in the public domain.

 

The newest items out are the new Geneva rootstocks.  They are all more expensive as they are

patented and there is a royalty charge per rootstock.  Dr. Cummins who has participated in this

forum in the past is now retired but had a hand in developing them.  They are generally good rootstocks

and attempted to correct some of the problems with the MM... series. 

 

The MM series was initially selected for easy rooting.  This has caused a problem in field with the stock

portion that resides above ground trying to form root initials.  The roots can't successfuly form, and the

tree forms something called a 'Burr knot'  This causes two problems.  The knot can grow large enough

to restrict vascular flow (strangling the tree) and it allows easier access for a group of boring catepillars

that can eventually kill the trees.

 

The Geneva series was purposely selected so it wouldn't form Burr knots.  This makes it more difficult to

root.  One or more of them forms spines, and one is a very good stock, but if the scion that is grafted 

onto it is virussed, it will kill the stock.  So you could say that the Geneva series may be better in the

field, but much more difficult in the nursery, while the opposite may be said to be true of the MM series.

 

If I've stated anything erroneous here, please step forward and correct me.  I'm pulling this from memory, having heard Dr. Cummins speak 2 years ago, and doing some reading also.

 

Chris Mauchline
SE PA, zone 6
40° 5' N 75° 51'W
~650 ft elevation