Peniocereus striatus in AZ

[peterb]

I have long been intrigued by the possibility of finding Neoevansia diguetii (Peniocereus striatus) here in AZ. A couple years ago I found a plant way down by Loreto in Baja California Sur, but I always wanted to find some in the US. Benson mentions the plant in _Cacti of Arizona_ and Earle also mentions it in _Cacti of the Southwest_. I'm a big fan of Peniocereus so it's long been on my wish list.

Yesterday I originally headed out to Sonoyta, Son. Mexico to look for the population of Echinomastus erectocentrus acunensis there, but then realized it was the Sunday after Thanksgiving and the return trip into the US was going to be a very long line indeed. So I decided to head down through Tohono O'odham country south of Why and look again for N. diguetii.

Finally found a couple plants, very far south, quite near Mexico. I definitely caused some curiosity among the Border Patrol agents down that way.

The first plant I found was only a few thin stems. They are not the easiest subjects to photograph! Not sure why it caught my eye. The camouflage is truly amazing:







The second plant, however, was a wild, Medusa-like older plant, half of which was dead above ground.









would love to see them flowering sometime.

peterb

[vlani]

Amazing! I always wounder how plants like that got discovered at the first place.

[peterb]

Yes, me too Vlad. People were very highly observant back in the day and had more time, I think. Many of th earlier plant explorers moved much more slowly through the landscape than we do now.

This plant truly does not even look like a cactus.

I think it's interesting what Benson writes in _Cacti of Arizona_. He calls the plant Cereus diguettii. He also mentions that it was called a Wilcoxia (erroneously, as those are more closely related to Echinocereus). Then he writes:

"Cereus diguettii has been collected...near Sonoita. *The flowers are white and nocturnal*. The plant occurring north of the boundary in the same vicinity is referred tentatively to this species rather than to Cereus striatus, which has diurnal, purple flowers."

By the time he wrote _Cacti of the US and Canada_, I guess he realized he was confused and called the plant Cereus striatus. However, there still seems to be confusion over the flowering:

"flower nocturnal or diurnal...petaloids white to pink to purple...."

I wonder if there is a more accurate or certain description of the flowers? I wasn't aware that cacti could have flowers that were either nocturnal or diurnal.

anyway, fascinating and delicately beautiful and odd plant.

peterb

[Tony]

Do you happen to know if P. diguettii prefers to grow in the company of that particular green barked tree? It sure appears to in the images you captured.
Or is that the ONLY acceptable type of tree/shrub growing in the area?
Does it appear that they have been reproducing well in the area? I imagine finding a young plant would be difficult in the thicket.

It is an odd thing either way... I like it.

[peterb]

Hi Tony- the diguettii I found in baja was growing with a creosote bush, I think. These shrubs are Canotia holacantha, the "Crucifixion Thorn," and in this area it does look like the larger plants prefer that shrub.

peterb

[tumamoc]

Very cool. Hats off to you for finding those! It looks like the branches of the tree are perfect for supporting the cactus stems.

[daiv]

I notice that Anderson lists Purple and Red for flower colors, but Juergen's plant has white flowers: http://www.cactiguide.com/cactus/?genus ... s=striatus

[peterb]

haha, thanks for that reminder Daiv! I forgot to look right here on our own forum for flower pics.

those are very different flowers from Neoevansia viperina.

peterb

[peterb]

The more I think about this, and after talking with Jurgen Menzel via email, the stranger this all seems. I am beginning to think that these two "synonymous" plants (Neoevansia diguetii and Peniocereus striatus) may actually be two different plants. Time will tell, I guess. At least now I have a reference point for some Arizona plants.

peterb

[daiv]

I will follow this with interest Peter. Did you mark your plants on the GPS?

[peterb]

Yes, I got the GPS. The locale should actually be quite easy to find again.

I will of course be visiting again! More photos to come, hopefully of flowers, fruit and seeds.

peterb

[Peterthecactusguy]

hmm whats the difference between Palo Verde and crucifixion thorn? Once again I am new to the desert and call all of those green palo verde (or Foothills Palo Verde) and have actually yet to see a crucifixion thorn owning to the fact that I though that they were much smaller then a Palo Verde tree.

[peterb]

I'm not expert on the trees and shrubs at all, I just know Palo Verde is a large tree without thorns and Crucifixion Thorn is shrubbier and has wicked spikes.

peterb

[Peterthecactusguy]

hmm interesting, cause Palo Verde also has spikes on the tips of the branches. either that or in BCC we have some of the largest Crucifixion Thorns around. Anyways in AZ what are the largest trees? hahaha think that my Saguaro is taller then any of the Palo Verdes that I have seen....who knows to be honest.

[peterb]

Well lots of different green shrubs and trees get called "Palo Verde," so I find it more helpful to use latin names.

The classic Palo Verde that is the state tree of Arizona is in the genus Cercidium. There are two of these, the foothill Palo Verde (Cercidium microphyllum) and the "blue" Palo Verde (Cercidium floridum). The bark of these two has thorns on it, but the branches are not spiky like the Crucifixion Thorn.

The Crucifixian Thorn is Castela emoryi. Then there's the "Mexican Palo Verde," or Jerusalem Thorn, Parkinsonia aculeata.

Anyway, I think the trees/shrubs the Peniocereus are growing in is Castela emoryi.

peterb