Help with possible fungus ID

[Melinda G]

Help please! Below are pics of several different lesions I have noticed on my Carpoxylon. Older leaves seem to be more significantly impacted. I have found several small, ovoid, flat, dark brown to black spots on the leaflets that are easily removed. However, I have also found irregular, black lesions at the base of a few leaflets, and today noticed some sticky, sap-like substance on a few of the leaflet bases/rachis. I am very worried this is a diffuse fungal disease. The Carpoxylon is kept under an overhang due to sun sensitivity. New spear seems to be coming in as expected. 

Any advice as to the culprit and treatment options would be immensely appreciated. I am very worried. 

 

Melinda

[jimmyt]

From the pics it looks more like either aphid or mite damage.  If aphids they leave a sticky substance on the leaves that promotes the growth of sooty mold.  The aphids and mites both will damage the leaves.  The sooty mold will wipe off.  I would double check them, both aphids and mites are easy to kill.

[David York]

I agree, the sooty mould shoud wipe clean and it indicates aphids, which are relatively easy to remove. The mottling however is caused by spider mites. Unless they are removed they will kill the plant. They are not easy to completely kill off in one go and it will take more than one attempt to totally eradicate them. They thrive in hot dry conditions.

[Melinda G]

Thanks to you both for your input! 

Everyone got a bath yesterday, and I wiped down all the individual leaves. Planning on repeating today. Do you have any specific treatments for the aphids and/or spider mites? 

I haven't seen any ants around, but I will definitely incorporate some ant control around the area. 

Thanks again!

Melinda

[David York]

Soapy water will work for aphids but spider mites are resilient and will need something more powerful. Do a search for an effective product that can be purchased where you live.

Also, potted plants need constant attention to keep them in top condition. Regular food and water will give them this. A healthy well looked after plant will be able to use its natural defences to fend off pests and diseases.

[jimmyt]

Treatment will depend on your approach.  Organic vs Man-Made chemicals.   Neem, mineral oil, eucalyptus oil, citrus oil will work to an extent but need frequent reapplication.  I tend to use Malathion + wetting agent, and be one and done with it.  The down side of malathion is that it is toxic, and has a lingering smell.  Not too much of a problem if the plant is outside, and you dont have plant eating pets.  If you use malathion on inside plants then unless you are nose-blind you will have to leave them outside for a while so the smell can dissipate. 

[Melinda G]

Thanks again! I’ve got some Neem oil on hand that I’ll start with while I research the rest. 
 

I do fertilize regularly and water q 1-2 days with collected rainwater. The palm is kept under an overhang as I don’t yet have adequate shade for it, so I worry that the air is too stagnant and/or it’s not getting doused with water frequently enough. 

I appreciate your help, 

melinda