still to be salvaged ? please help! all comments welcome!

Hello everyone!

I once had a large collection of cacti, but due to professional reasons had to leave it with my parents, who unfortunately did not know how to cultivate these plants (and ignored my advice...) and most of them sadly perished over the years.

In a desperate attempt to save the last remains of my once vast collection, I have recently recuperated the last 8 specimen, stripped them off most soil and roots, extensively washed them, treated them with dimethoate against bugs (lots of mealybugs and probably many more) and (after appropriate time of rest to let wounds dry) potted them in new soil on a south-ward oriented window here in Paris :



The plants now receive direct sun from noon till late evening, though days are still a bit cold and moist (not best conditions I know but hopefully soon to change - May in Paris is usually quite sunny and warm already; also this will prevent them from burning, I did not want to use shading).

Now these plants did not only have bugs, but also ugly colorations and corky parts, most probably caused by fungi and/or diseases, probably caused in part also by the bug attack and too wet conditions over the last years (I think the principal reason my collection perished was bad ventilation).

It has been long since I have dealt with these things, and it would probably be easier to dispose of some of these plants alltogether, but for sentimental reasons (some are more than 15 years old and grown out of seeds by myself) I want to try to save them all. I'd greatly appreciate your help with this!

I would be most grateful for any indication as to appropriate products to use (names of ingredients rather than brandnames please, as these probably differ here in France), procedures, etc.

All spots and colorations are dry and solid, no wetness and/or softness and no bad smell.

The Neobuxbaumia on the left is most attained, it has started to develop black rot(?) from top down.



It has corky and brown/black spots all over, as seen on previous pic, especially corky near the base -



- with one side of the base totally corky but a lighter colour:

These corky parts do not look like ageing to me, or could they be?

The Pilo next to the Neobuxbaumia has some yellow brownish colloration.



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Here a close-up of the central yellowish-redish spot:



Is this a fungus?

The Gymno stelatum and Euphorbia obesa also have a pretty bad looking coloration.





These also don't look like ageing to me. Anyone an idea?

The Euphorbia also has some ugly white spots.

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I'd have said it's just dried sap, but I couldn't manage to wash it off !?

The Mammilaria seems fine (anyone know the specie by the way ?):



But it's yello at the bottom on the base of the nipples:



Fungus? Disease?

The Pachycereus only has some cork at the top which might have been a burning. It seems to grow out of it now:

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Not serious I guess (?)

I know there are a lot of questions here, but basically I'd just like to know if you think I can save these plants and how. Any contribution appreciated! I'm looking forward to your comments!

thanks a lot

Jerry

Hi Jerry,

These plants are really in a bad shape
You must first give them good treatment, but that's probably what you are doing.
If they have no sentimental value, just trash the worst ones.
Or try to make them produce offsets, and then start fresh plants from them?

Yann (France, Clermont-Ferrand). Serre tenue hors-gel + pleine terre un peu abritée. -10°C tous les hivers.

yeah...

I wont trash any of these, I'll try save them all, through offsets for the neobuxbaumia, and the rest I'll probably watch them for a while and see how it goes. I posted this up here to see if anyone would be able to tell me a precise treatment, in case they could identify any specific disease or plague. But so far I have not received any such.

Thanks for the comment though!
Will post here how the plants are faring

Cheers

Hi jerry. The Neo needs surgery if the rot is soft. Don't spare the knife. Most succulents cannot wall off fungal rot since they have not evolved in such cnditions, so I would cut the top off and let the rest cauterize. If it lives, it will always be scarred, but it will also likely grow some offsets from undamaged aeroles. So far as the Mamm, there could be mite damage if the new growth also is affected. Corking in and of itself is not too damaging, but it usually indicates other problems, as you probably already know. A good systemic helps, also a spray with undiluted isopropyl alcohol won't hurt. Alcohol cures some mites, all scales and most mealies. Since it is topical, for total control I use it 3X, once every 3 days for a total of 3 treatments in 9 days.
I am a thousand miles (1300km) from my plants and my library I cannot help with ID. I will say though, that I also have this plant and it is distinct enough that it isn't confused often. Maybe M. mystax?

Thanks Peter!

Since these plants are permanently outside, I was waiting for the sunny days to arrive to cut the Neo so it would properly dry, but they have kind of taken their time this year... Hardly two days in a row without rain or really wet and cold weather since the beginning of March. Today looks like summer just arrived but they're forecasting rain for tomorrow again, so I guess I'll just have to wait a litle longer and hope the Neo will make it that long (these plants have probably been sick for long so I guess a few more days wont make a difference). How long does a columnar of this size need to dry in your experience? Will rain two or three days after the cut likely damage the plant? (They usually don't get rained on but when a lot of wind is accompanying the rain it can happen).

Thanx for your product info! What sytemic are you referring to though? A systemic fungicide? Or insecticide? And the alcohol against fungi or beasts? You think these plants have mites? Actually I treated them extensively with dimethoate and removed all their roots beforehand, you think they could have survived that? Also what do you mean by topical?

Thanx for the identification also! Just googled M. Mystax, mine definitely looks like one!

Cheers,
Jerry

Hey Jerry. Over here we have a systemic by Ortho company that works well, I have no clue what is available over there. Maybe there are some listed under "Culture" at left.
I don't think fungicides will do any good at this point, besides all the fungicides I know of are topical. Topical= they are only effective on the surface. It also means they only kill what they actually hit, that is, they have no residual effect. Some sprays stay on the surface and continue to kill (like Sevin), isopropyl alcohol is topical.
I can't say if they have mites. Some of the damage looks like mite damage, but they may be gone. If you see small webs between ribs/spines, that is indicative of spider mites. Also, corking (bark development) can be indicative of mite damage.

I would not wait for sun to cut, I would cut and bring the plant inside. Fungal rot travels throughout a cactus' vascular system in a few days, or hours.
Any new pics? (In a new post if you wish, of course.)

Thank you!

will post new pics soon.

(Very interesting the story of Joual by the way - just wikied it, had never heard of it before)

Jerry