Red Bumps on Leaves

[Jackie Paper]

Hey Hey!

Awesome blog, lovely interface and design. Could anyone help me figure out what this is? I am from South Africa, and I am not sure what the name of the tree is that has the problem but I can find out if needed:

[applestar]

That kind of growths are typically called "galls" Usually there is some kind of insect that lay egg inside the leaves that causes them. My oak tree gets them from tiny little wasps, but the damage is not significant enough to harm the tree.

I don't know what kind of tree or insect is involved in your situation, so the extent of the damage may be different and you may need to control it. I have a Liquidamber tree that I am hoping to turn into an bonsai, and when that tree developed leaf galls, I just clipped off and destroyed the affected leaves.

[Jackie Paper]

Great, thanks so much Applestar. We have been clipping off the infected leaves, but it never ends, and the tree is getting rather large now. Good to know its an insect causing the issue, I'll look out for it!

[rainbowgardener]

Yup, some kind of insect gall. Usually the insect lays an egg with some kind of growth hormone type chemical that stimulates the leaf to grow around it like that. Provides a nice safe enclosed space for the larva to hatch out and grow, protected from any predators. Eventually the larva emerges, metaphosizes into adult and starts the cycle over.

My big old hackberry tree gets covered in these, formed by a tiny psyllid insect. It seems to do the tree no harm.