How to stop pests eating Robina Mop Top?

[CWILSON]

Hi There something is eating my leaves on my Mop Top. Leaves have big bites out of them and some leaves are curling.  Please see photo.

[JacobZ]

Hi @CWILSON,

Welcome to the Bunnings Workshop community, it is wonderful to have you with us.

Based on your photo, it seems likely that there is some kind of insect eating your Robinia Mop Top, but unfortunately, without seeing what is eating your plant, it would be extremely difficult to recommend a suitable approach to fixing the issue.

Can you see the actual insects or evidence of these insects on your plant, such as eggs, webs or scaly deposits? If so, can you snap some photos and upload them?

As insecticides are plant and insect-specific, we would need to identify what is attacking your plant before we could recommend something suitable.

Let me know what you find.

Jacob

[CWILSON]

Hi Jacob

We have searched many times and can't see anything groan :-(.

[JacobZ]

Hi @CWILSON,

If you can't identify the insects, it is going to be best to focus on the overall health of the plant, rather than eradicating the insects. With better health, it will be better equipped to fight off an attack.

The first thing you should do is ensure it receives adequate water, especially during dry periods. You'll want to water deeply once or twice a week, checking that the top 5-10cm of soil dries out before watering again. Overwatering can be just as bad as underwatering, so checking that the water is draining before watering again is essential.

Fertilising with a balanced, slow-release fertiliser like this Scotts Osmocote Total All Purpose Controlled Release Fertiliser will also support healthy growth and improve the tree’s ability to recover from insect stress. 

Pruning any dead or damaged branches will also encourage new growth and improve airflow through the canopy, which can help deter pests and diseases.

With consistent care and maintenance, your robinia should gradually strengthen and become more resilient against future infestations, but if you can ever identify what is eating it, we could look at more specific methods.

Allow me to tag @Noelle to see if she has any thoughts.

Jacob

[Noelle]

Hi @CWILSON 

I echo Jacob's comments that it's almost impossible to identify what's chewing your robinia's leaves without a photo or two. However, from the damage pattern, I'd think either beetles or caterpillars. Damage like this can often be seen on trees chewed by beetles like the Christmas beetle (although this particular one sticks mostly to eucalypts).

Because you haven't been able to find the culprits, I'd suggest it's most likely beetles, as they can fly and will often feed at night, hiding during the daylight hours. A foray into the garden at night with a torch could be of help in finiding the pest.

Meanwhile, maintaining tree health is important in aiding the tree to re-shoot and overcome the devastation the pest has caused.