AusBonsai

So a few months ago I noticed my Zelkova and Japanese maples weren't doing too well. They both were getting some brown spots on their foliage and just generally not looking great. Initially I thought it was perhaps over watering or maybe too much direct sunlight, so I tried to rearrange them and water them a bit more intelligently.

My Zelkova picked up and had some really strong new growth but my maples seemed to just get worse. I decided to take a closer look at the maples and noticed lots of black dots all clustered together. After a bit of a google I found they were Aphids and unfortunately I couldn't save the maples as they just looked too far gone.

Although my Zelkova was looking better I have recently noticed its foliage has started looking worse for wear again and, after taking a closer look, I noticed a lot of small white dots all over the underside of the foliage. I am assuming they are Aphids considering the Zelkova was next to the Maples but I am not sure as they don't seem to be moving or have limbs of any kind.

Does any know what these are and how to treat them properly?

Look like aphid eggs. This time of year just cut the leaves off and bin them they are all going to drop in a few weeks anyway. This way you can throw the leaves away and get rid of the pests before they hatch.
Cheers
Kirky

Ditto to what Kirky said, but it is a fair sign of aphids when you see ants.

Thanks for the help Watto and Kirky!

I've cut off the leaves of the Zelkova so hopefully that will do it. I'll keep an eye on the neighboring trees to make sure these annoying bugs haven't spread. It's a shame I won't be able to see the leave change colour this year but hopefully there will be many years to come for this tree!