Division of Mammillaria?

[untaken]

I have what I believe is a Mammillaria which has florished over the past 15 years. Years ago, it separated its growth into two shoots; it looks like a letter V. Each is proportionate in size to the other, but they now have become so large that they each have their own center of gravity and weight that are overwhelming the base, they are starting to split the base apart. Should I just finish what the plant as started and divide the remaining part of the base and divide the root system, replant each half, let the cuts heal over and nurture the two resulting plants? The only other alternative I can think of is to prop up each side, but each side is so large that the base will never be able to take the stress and remain one piece.

[daiv]

Sounds like the dichotomous splitting that is typical of some Mammillarias alright.

I think either of your proposals are perfectly acceptable.

Daiv

[phil_SK]

I'm sure it would be preferable to leave it in one piece, if possible. Any chance of a photo?

[iann]

A photo would let us give better advice. I have a vision of a dichotomously divided plant (more a "Y" than a "V") getting axed down the middle, roots and all, and the result being two very ugly mishapen plants

[untaken]

Thank you for the replies. I'll try to round up a digital camera and post a photo (depending upon your viewpoint, either I'm a purist or a Luddite in continuing to use my film cameras). But it really is V shaped and not a Y. Early on, when they first started,the two sides were about two inches above a single, columnar base (Y shaped). However, over time, the two sides have grown (now about eight inches each) and the original two inch base is only the plant's thickness/height between the bottom of the inside crotch, formed by the two sides, and the soil level. The plane lines parallel to the outside edges of the plant's two branches enter the soil at an angle, there is no part that is perpendicular to the soil level.

[untaken]

Two (poor quality) photos that show the plant and its shape can be viewed at http://picasaweb.google.com/SandyMooy They are in web album "Cactus"

[daiv]

OK, that looks a bit like M. spinosissima to me, which does not split dichotomously. Even if it isn't spinosissima, it isn't a dichotomous split.

I suspect that this plant put out an offset when quite young or is two seperate plants that have been potted really close to each other.

The smaller diameter growth at the bottom suggests poor light conditions in the past. Aside from simply bearing the signs of old age, it appears quite healthy now.

Even so, should be fine with either of your own suggestions as to what to do.

Daiv
PS. Here is a dichotomous spit:



Sometimes they go in more than two splits:

[phil_SK]

The two look nice together; it would be a shame to split them. If they're no too wobbly I'd leave them as they are. Or prop them up as inconspicuously as possible - maybe tie the two together low down with a loop of fishing line?

[cactuspolecat]

Another option would be to pot them in a semi prostrate position so both stems are leaning the same way and will eventually 'lie down', this would take much of the strain off the area where they join.

here's a some of my dichotomous plants...
Mamm. muehlenpfordtii (celsianus) which is what I think yours is. this is getting to the stage where i shall re-pot and lie the plant to it's side.


Mamm. karwyinskiana ssp. nejapensis.


And my little Mamm. crucigera... this plant is in excess of 20yo and is just little over 50mmm across...


CP

[hob]

i find this dichotomous thing interesting.........is it just limited to mammillaria ........or do other species split dichotomously ???