Help needed for jacaranda tree

[mizzoumom]

Can anyone help me with this jacaranda tree? It developed this hard growth on the trunk?

 

[Chuck]

That hard growth is hard scale insects. At first I thought it was some physiological aspect of the tree but upon looking closer I was able to see a few individual insects. It is rare to see this much of a buildup of these harmful insects. These sucking insects have a hard coating and are just about impervious to insecticides. They are permanently attached to the tree and will not voluntarily fall off when killed. The tree will grow, expand and finally force them to fall off. The best way of killing them is to smother them, cut off all of their oxygen. The best thing I have found for this is Neem Oil. You must spray the entire tree, trunk, limbs, stems and leaves and totally cover every inch of the tree. With this many insects it will probably take 3 or 4 sprayings to assure that they are all dead. Spray about every 6-8 days. Spray in the AM hours or late afternoon, not in the heat of the day. The tree is either a semi-evergreen or deciduous depending where it is located but I would guess that in Missouri it would be deciduous. After leaf drop will be the most opportune time to start spraying. Having said all of this I beleive that you are seeing two things, one, the insects and two, a physiological phenomenon which could possibly be the tree beginning its growth of true bark but in any case there are hard scale insects shown in the pictures

 

[mizzoumom]

Thanks Chuck. I was able to clear the tree of scale. I had sprayed the entire tree with neem oil and those I didn't get with neem, I got with a q-tip and alcohol. I even scraped some of the brown off the trunk without seeing any scale insects. I'll keep checking for insects/scale. In the meantime, I'll try to look at some of the scrapings under the microscope.

 

[YumYum]

Can you post a pic of the same limb after? Just interested in seeing the outcome.

 

[mizzoumom]

I will post an after picture. I’m going to watch things closely until then.

 

[mizzoumom]

Here is the progress so far using neem oil. Then using the back of an exacto knife to scrape everything off as much as possible without damaging tree tissue. Then another dose of neem. A lot of the white dots are light reflecting off the neem oil.

 

[YumYum]

Wow, that is a big difference.

 

[cpp gardener]

They sometimes do grow bumpy structures on stems and petioles. Check very carefully before scraping the stems. It won kill the plant but scars them up a bit. They usually only do it on one side of the stem And not all the way around.