Fungus?

[Marc]

Could you show us wat kind of material compo mix is?

 

[bricki]

Sorry, I have finished all my packages...
But here is the link:
http://www.international.compo.com/en/consumer/blumenerde/composana.html
Maybe it's not the best mix, but it's only what I have fast...
About spider mites - I think there are some on the down side of the leave on the last picture (I'm not 100% sure about the type of bug )
Now tell me please, where to read about these monsters!!! :evil:
How to kill them???

 

[Marc]

You can gently rub down the bottom of the leaves with a piece of white toilet / kitchen paper. If small red streaks apear it probably are spider mites.

I've treated versus spider mites with an insecticide a few times, but last time one plant had a few mites on it I took it to the bathroom and hosed it with the shower head from all directions. Since then they haven't returned, spider mites don't like it too humid.

Regarding the potting material you have used. I'm a bit worried there, I've seen a similar material and allthough it has it's uses I wouldn't use it for my Paphs. Because of it's peat content it tends to compact and if it compacts root loss is around the corner.

 

[likespaphs]

you use their orchid mix?

 

[bricki]

Yes, I do!
I know that is not the perfect for paphs, but it's temporary...
I hope to gather ingredients for more appropriate mix, till next year!
Any help will be appreciated!

 

[SlipperFan]

Mark's suggestion is good. If you have a strong magnifying glass, you might actually be able to see the mites with it -- they are very tiny. There are two kinds: red spider mites and two-spotted spider mites. Ray (First Rays) sells something called SucraShield that worked very well for me when I had an outbreak of mites on my Paphs and Phals a couple years ago. I don't know if he ships overseas, but you might ask him.

 

[Rick]

Most spider might problems are also associated with too dry (low humidity) conditions. As Marc pointed out.

Unless these turn out to be the special tropical kind, you can usually eliminate spider mights by keeping the humidity up higher (>60% RH).

If you are running dry, then you will probably be surprised how much better your plants do in general with a humid environment.

 

[likespaphs]

i don't think that the sphag on top will help with humidity but i could be wrong

 

[Stone]

I can't see any splitting, just drying out of the tissue.


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Ok Sorry to bring this up again but its still occuring here and there and really giving me the #%$^*&(*(*) not knowing what's causing it.
Some info: Mostly on seedlings, one bellatulum in a compot of 4 otherwise perfectly healthy, good color, glossy leaves, good roots. both hainanese in a compot, otherwise good health and growing fast. Low fert levels, calcium provided. an appletonianum, concolor, urbanianum, roth and sanderianum all have it, but again all growing well. I think humidity is ok ( 60-70%) Plenty of air. Min. temp during this past summer- about 65F. 18-20C Max. about 95F 35C for a short time only, usually max. of 80F 27C. Does not progress further than in the pic. (usually not even that far) Not present on other paphs treated exactly the same!!!!!!!!!!!!!!!!!! Not mites. Someone??? Anyone seen this/knows what it is?? I noticed the pic of concolor in L. burk's book has it. I can take more/better pics if it will help.
Thanks for any thoughts.

Mike.

 

[SlipperFan]

It looks like residue from water that sits in a cavity in the leaf. The water evaporates and leaves that residue.

 

[Stone]

It looks like residue from water that sits in a cavity in the leaf. The water evaporates and leaves that residue.

No thats just a bit of fugicide Dot. What I'm talking about is browning on the extreme tip of the leaf and it only progresses down the central vein for 2-3mm and then stops.

 

[Roth]

Someone??? Anyone seen this/knows what it is?? I noticed the pic of concolor in L. burk's book has it. I can take more/better pics if it will help.
Thanks for any thoughts.

Mike.

It is a micronutrient deficiency, but very hazardous to correct directly. You should be careful to lower a bit your potting mix pH, lower the calcium applications and use some organic stuff like fish emulsion to correct it as a spray ( not kelp). It will work just fine. I have seen some thousands plants affected in the Netherlands some years back, multifloral hybrids and Primcolor etc...

As an aside, it can develop a couple years later in a total plant collapse, especially after flowering. That deficiency first makes the plant grow really fast and nice, then there start to be that leaf tip thing, some older leaves are not as clean green as they should be, and at a later stage, if they are really very deficient, you can loose most of the leaves within a week or two. Most of the time you will never reach the extreme deficiency level. It is a translocatable micronutrient, but slowly, and the stocks once depleted cannot be replenished in the older tissues...

 

[Stone]

Thanks for replying Roth. Yes I did check the pH of a selection of pots yesterday and found an average of around 5.5-6. I have not been adding Dolomite/Limestone as I believe most paphs seem to do better with a slightly acid p/media. but I think 5.5 might be getting a bit low. All my water is very pure in fact my mains water has the same pH as my rain water- 6.3 approx. and effectively 0 EC.
I can supply Ca with cal-nitrate but I think this will take a long time to bring up pH .5 or so. I have been feeding with 50/50 organic ( home made Japanese recipe + blood and bone and 50% Hydroponic solution at very low rate. I have been trialing this feed on some perennial cuttings and seems good. Also use kelp and humic acid from time to time. Maybe this is a watering issue??????????????????????????? I will find out eventually. I'm sure the solution is staring me in the face.

 

[Stone]

 

[vinhpicohp]

Some of my friends are still discussing about fungicide to treat fungus on orchids as those ordinarily comes into their media. I wonder whether it will contribute the risks to Symbiotic fungus, which decomposes the media and benifits the orchids?

 

[Stone]

Some of my friends are still discussing about fungicide to treat fungus on orchids as those ordinarily comes into their media. I wonder whether it will contribute the risks to Symbiotic fungus, which decomposes the media and benifits the orchids?

From what I've read, mychorriza at least, is not greatly affected by most non-systemic fungicides. I try to keep all fungicides down to a minimun anyway. I don't believe the above problem is caused by a fungal infection.

 

[vinhpicohp]

From what I've read, mychorriza at least, is not greatly affected by most non-systemic fungicides. I try to keep all fungicides down to a minimun anyway. I don't believe the above problem is caused by a fungal infection.

Greatly thanks! Neither do I, keep all fungicides down to a minimum

 

[Stone]

Ok, I'm going to go out on a limb and speculate. I no longer have this problem! New leaves are good. So the only thing I've changed is cutting down on the Calnitrate and gypsum and upped the Boron and Ammonium a little.
Maybe too much soluble calcium in the media/not enough B?? Just guessing!! If you look at various pics of B deficiency you often see a kind of corky tissue forming which is what this looks like up close. But again....?????

 

[Ozpaph]

nice photos, thanks. Keep us informed