What's attacking my palms?

[Neofolis]

I've noticed that two of the stems of my Dypsis (heteromorpha?) have something on them.  I assumed it was just part of the plant, but having observed the plants again today, it has spread dramatically in the past two days even to neighbouring plants.  It is like small brown lumps on the surface.  The are easily removed and the flesh beneath has lost it's pigment.  I've looked at pictures on the net and it looks most like some kind of rust, but it is much lighter, a kind of tan colour.

If anyone can identify the problem and also tell me how to clear it and hopefully prevent future attacks, I'd be very grateful.

[Neofolis]

I got impatient waiting for answers and decided to take action.  I have sprayed everything with a systemic fungicide, which contains Penconozole and also purchased some Drithane, which is mancozeb based for future fortnightly applications.  Unfortunately, I can't get Daconil in the UK or anything else chlorothalonil based, but from what I read on the internet mancozeb based products are usually as effective.

Apologies if any of those spellings are wrong.

[mppalms]

Perhaps you are keeping your D. heteromorpha too hot?  I have two in pots shivering (along with me) through days with 10-12 C max and ~5 C min, and they seem happy enough.  

Of course, I think these are supposed to be from northern Madagascar; so, I'm not sure how much of a seasonal change they see.

Jason

[Davidl]

Looks like bugs from what I can see maybe scale or another bug.Malathion or Systemic insecticides, such as those with the active ingredients acephate, dimethoate, disyston and imidacloprid, move into the sap system of the plant and then kill them. I am not positive thats what they are but if you can show a close up it might help.

[Neofolis]

It is kept warm and that may be making it more susceptible to attack, but, whatever the problem is, it has spread to other palms, so I still need to get rid of it.  This Dypsis has been kept warm for the previous 2 years without any problems, so I doubt that that is the only problem.

[MattyB]

It's hard to tell from the photo but I was thinking scale or mealy bug too.

[BS Man about Palms]

Generally look for ants. If you see ants, there is scale usually nearby. They kinda have a co-op thing going on. Use Malathion.

[Neofolis]

Thanks for your thoughts everyone.  I haven't seen anything that moves, but I will try to get a better picture.  I have already removed the superficial stuff manually, but, as mentioned in my first post, it has left spots with reduced pigment beneath.

[Neofolis]

OK, I have taken some photo's.  On the plus side, although my palms may be suffering, at least I have discovered the benefits of macro mode on my camera.  Hopefully these are close enough and clear enough for a definite answer.

This first picture is the base of one of the Dypsis heteromporpha stems.  Whilst I thought I had cleaned it all, the photo clearly shows the white residue, after cleaning, but at the very base there are still plenty of whatever it is.

The next two pictures show an area of my Chamaedorea cataratarum, that is adjacent to the Dypsis in picture one.  This area has not been cleaned and whatever is on the plant is much clearer here.

Finally, this is the same area of the Chamaedorea cataractarum after removal of the growths, clearly showing the white residue.

[Neofolis]

Thought I would bump this, in the hope that the new pictures shed some light on the problem.

Thanks in advance anyone.

[mike453]

Corey,

after seeing the close-ups, I agree with Matty & David. I believe insecticide is needed.

                                 Mike

[BS Man about Palms]

Corey, without a doubt, you have scale.  If you have Malathion, use as directed.  Again, look for ants, if you don't see ants they may be dead already (unless increasing in quantity).  They look about the same dead or alive.

[BS Man about Palms]

Oh yes, if (or once) dead, you don't need to remove, other than for looks.

[tjwalters]

Definitely scale.  I would try a systemic insecticide applied outside and according to directions.  I've used Ortho products (Orthene?) before with good results.

[Neofolis]

OK, I'm going to be a pain now.  Because I generally prefer to use biological controls, I wondered if anyone knows whether this is a hard scale or a soft scale.  There is a biological control (Metaphycus helvolus) for soft scale, available in the UK, but nothing for hard scale.  They don't seem soft when I remove them, but then sometimes such terms can be misleading.

[Neofolis]

Thanks, by the way, everyone.  Hopefully, I will recognise them myself next time.

[Kris]

Dear Neo  

your new stills are clear enough for me to understand that its what is commely seen in our hibiscus flowering plants,yellow latania & phoenix sylversteris..this happens when cold rainy season fades giving way to mild warm spring or summer season..i get these things in my plants,i trim my hibiscus,for the latania i take a cloth with mild soap solution and wipe it clean and as for the sylversteris,i never water it !

and i use ant powder and malithion only..but in my case i see lots of red ant moment too ! but it is easily cureable until next season ! here are few stills of my affected palms..

love,

Kris  

[Kris]

One more still of the same palm(yellow latania)_

[Neofolis]

Thanks Kris, I feel a bit better about my palms now, knowing yours survive that each year.  I did a quick search through some of the online suppliers I use and couldn't find anything Malathion based, so I went to a local shop and bought a ready to use contact/systemic pesticide, which is Thiacloprid based and sprayed it everywhere in the polytunnel.  I will give it another go in a couple of weeks.

[Mats]

Corey, here are a couple web sites that will give you some more information about your scale problem.

Integrated Pest Management - Scale  

and

RHS - Scale

[eastern.nurseries]

fipronil is a new generation of chemical that is very effective for this situation

[Neofolis]

Interesting articles Mats, although it is a bit of concern that there are so many species of scale and they each respond differently to the different pesticides.

Thanks Jon.  When I had a look, there seemed to be quite a limited choice of pesticides in the UK.  Hopefully what I used will work, if not, I'll look for an alternative.