This is from the old German Trichocereus macrogonus stock believed to be descended from the Berlin material.
   It is now most often propagated for and used as a grafting stock due to:
   1) the newer plants now called macrogonus being perceived by growers to be more attractive
   and
   2) seed stock for the old Berlin plant being unavailable.
   That newer material showing yellow spines with black or dark brown tips has largely displaced this in horticulture despite seemingly no one knowing how said newer material came to be assigned the name Trichocereus macrogonus or even why it should be regarded as macrogonus.
   ALL occurrences and offerings of this newer material which we have been able to track back to their origin arose from seeds provided by Karel Knize but Harry Johnson brought at least one wild Trichocereus macrogonus collection into US horticulture as well during the 1950s. We have not been able to locate bona fide Johnson stock yet.

Photo courtesy of Gerhard Köhres	Photo courtesy of Gerhard Köhres
Cutting propagated specifically for use as a grafting stock in Germany.	Cutting propagated specifically for use as a grafting stock in Germany.

Photos of grafted plants.    These were presented in an online discussion as being grafted on pachanoi but since none of Backeberg's photos of pachanoi look like this we would suggest these are more likely grafted on new growth of the old macrogonus such as is also shown above.    We were told by M.S. Smith that these came from Backeberg's Lexicon.    If our inclusion of these snippets here is found objectionable PLEASE let us know and we will remove them immediately or will offer fair compensation for their use.

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