Trichocereus peruvianus BK08612.4 from Matucana. Very cool glaucous blue type! Pics: Ben Kamm, sacredsucculents.com
This collection is known for its frosted blue epidermis. The populations in Matucana grow at around 2000 meters and Matucana was originally given as the type locality of Trichocereus peruvianus in Britton & Rose´s book THE CACTACEAE.
Karel Knize sold Trichocereus peruvianus from Matucana under various names, sometimes even under the collection KK242. Knize assigned his numbers to certain areas (eg Matucana), and collected from various different mother plants under that name. This means there are like 20 different collections of KK242 and every one is different. The KK242 that I know have very little in common with the plants shown on those pics. The Matucana Peruvianus that Knize was offering was called Trichocereus peruvianus KK242 forma Matucana. These pics are from the Sacred Succulents Field Trip om 2008 and they actually gave a whole lot of seed away. I hope to show some of the offspring really soon, because some of my friends were actually lucky enough to get some.
Where to buy seeds and plants of Trichocereus peruvianus from Matucana?: In my opinion, the currently best collection is Icaro DNA and Los Gentiles. Both of those might actually be the same population.
In addition, check out the Sacred Succulents catalogue for cuttings of this collection. They did collect a lot of seeds, and they have cuttings sometimes too. I assume that in the next year or two, there will be some cuttings available from people who actually managed to raise some plants from that seed.