I have this brown stuff growing on all the leaves on my pear tree in my garden.

Does anyone know what this is? I think it might be some plant disease.

Does anyone have any advice on fixing this?

  • A few pictures would be really helpful. There are readers from all over the world here, in the Caribbean a "pear" is most probably an avocado, in temperate zones more likely the apples and pears variety. "Stuff" is a bit vague as you can imagine; these issues would be resolved very quickly with a picture of the whole tree and a close-up of a normal compared to an infected leaf. Sep 8, 2018 at 14:12
  • the stackoverflow app failed to upload the image. had to do it over the web.
    – X0r0N
    Sep 8, 2018 at 14:29
  • Its definitely Pear Rust, but the link provided in the answer below doesn't give the full story - pear rust is a gymnangosporangium rust and it needs both Juniper and Pear to complete its life cycle, which is not information contained in that link. Here's some more up to date information, although its a UK one rhs.org.uk/advice/profile?PID=236. There's little point in removing any junipers you may have - they're a very common plant and the spores travel a fair distance anyway, but judicious and timely pruning of any you do have will reduce the level of infection.
    – Bamboo
    Sep 8, 2018 at 15:42

2 Answers 2


Aha, thanks for the picture, makes all the difference. Here is a link to Pear Rust Gall; please take a look at the information provided and see how it compares. There are other pages addressing the same issue on pears that may also help narrow it down. Are you in the UK?

The fix for this is to prevent spores from reaching the pear tree. The alternate host for the fungus is junipers, so keep an eye on local junipers to see if they show signs. If so, consult with your local experts what can be done. Also collect and burn infected leaves as soon as possible.

  • Yes I am in the UK. It looks like pear rust as you suggested. It seems all the leaves are infected. I guess I'll figure out how to burn the leaves.
    – X0r0N
    Sep 8, 2018 at 15:48

Rust is really common every year on pear and crabapple leaves. They're closely related. It's just ugly but the tree will be fine. I haven't seen rust on ornamental pears. it shouldn't affect the fruit.

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