Question

Yucca leaf   QUESTION: We have a Yucca tree that is about 5 years old and has spotted brown patches on some of the leafes,with sticky drops,on the brown patches,that look like honey droplets.Nobody in South Africa reconize these symptons and can give us advice on this or give us advice.Can you please help us to save our tree and give us some advice on treating the disease?I have a foto of one of the leafes and will sent it to you with this email.

Thank you very much!!!

Regards,
Cj

ANSWER: Cj:
This spot MAY be caused by a fungus called Cercospora.  Use your computer to "Google" Yucca leaf spots or use "Google Images" to see some aditional images. Also, look around on the leaves for any insect suspects- just in case. Many things can cause this kind of spot.  Be sure nothing is dripping on the leaves from above. If it is a true plant disease fungus, most of the spotted leaves are usually near the bottom of the plant.

Some things that you may consider doing.

(1) Remove/destroy any dead or fallen leaves- cleanup around plant.  If possible, burn all of this debris.
(2) If feasible, remove leaves with spots and destroy. Do this on a day when the leaves are dry.
(3) Water your tree at the soil level (avoid wetting the leaves)when it needs a drink.
(4) Not sure about the availability of chemicals in stores there, but if you have a nursery/garden center take a look at a fungicide called IMMUNOX or DACONIL. These can be sprayed on the leaves and may prevent new spots from forming.  Best to apply to the newly developing leaves.  Complete coverage of the entire plant is important.  Best to mix and apply according to the directions on the bottle.  Be sure to spray on a day when no rain is expected for at least 3 hrs.

Hope this helps.

Steve



---------- FOLLOW-UP ----------

QUESTION: Just to confirm.Our problem leafes are about a third from the top of the tree and we checked for the spiders.We have spotted small little spiders on the plant,between the leafes.Do we still use the same treatment as you instructed?Thank you very much for your advice!!!

Answer
Cj:
I do not suspect that the spiders are involved. It is best to get an accurate diagnosis from someone you could examine the leaves under a microscope to confirm Cercospora, however if you do not have an agricultural office in your community to carry some sick leaves for an exam, then go ahead and try the materials I suggested AFTER doing the cleanup methods etc described.You may try spraying a small section of the plant just to be sure there is no injury.. If any occurs, you should be able to see it after 3-5 days after spraying.

Steve