Ants attacking my plum tree

[GojiBerryCrab]

Hi everyone
Can anyone help me with a problem I seem to have with my Plum Tree?
Firstly I'll describe the tree. I don't know it's age but it's around 2ft high. It's a Prunus Avium.
The problem is that there are small a few red 'blobs' just below almost every leaf. It didn't worry me at first, but then I noticed ants on most of these blobs, and it knew it wasn't coincidence. Are the ants eating the blobs and the blobs are natural parts of the tree, or have the ants even created the blobs (e.g. eggs?!) . I don't know what to do!
If anyone can diagnose the prblem (if there is one) or/and give me any advice, I would be very grateful. I really don't want the infection to get to my beloved Goji Berry Tree!
Thanks!

[GojiBerryCrab]

P.S. I just want to add that I live in Britain, so we might have different diseases than the USA, which I've noticed most users are from. I don't know if that helps. I also want to add that the ants were black - again, I don't know if that helps. So, give any advice you can please! Thanks!

[tomc]

P.S. I just want to add that I live in Britain, so we might have different diseases than the USA, which I've noticed most users are from. I don't know if that helps. I also want to add that the ants were black - again, I don't know if that helps. So, give any advice you can please! Thanks!

My guess, will be resolved by your examination. A magnifying glass will reveal I expect that the ants are busy with aphids.

If there are aphids, a strong spray of water will wash most aphids off. Repeat as needed.

Aphids are also very suseptible to diatomaceous earth or insecticidal soap. Again repeat as needed.

If you treat for aphids (what I think your problem is) often enough, the ants will depart for gentler neighborhoods.

[applestar]

My cherry leaves have small red blob/knob where the leaf narrows to stem, so they may be the same for your plum.

I agree it's likely aphids or other sucking pests. Right now, I'm on the lookout for curled up leaves which indicates heavy infestation of aphids inside the leaves.

[DoubleDogFarm]

and leaf curl can be a worm also.

Do you have Tanglefoot in Britain? It's a vary sticky substance you can put around the trunk low on the tree. I usually apply it about 6" up from the ground. A couple inch wide band. The ants will stick to it if they attempt to climb.

Like stated already hose off or use Safer soap to remove the aphids.


Eric

[JONA878]

There are at least two sorts of aphid that will attack plum in the UK.
The first is the more dangerous to the tree as it courses the leaves to curl over making getting at it very difficult. This is a black coloured aphid and happens early in the season around the flowering period or very soon after.
Along with this is the Straw Bed Aphid. As it name suggests it is straw coloured and is not such a prolific breader and although a pest does not cause such damage as the black fellow.
This one does not cause leaf curl and can be ' got at ' with either soapy water or an aphid specific pesticide.

[GojiBerryCrab]

I've taken some pictures of the 'blobs', and the ants on the blobs (which is a bit blurry sorry!)

Do you still think they're amphids?
[img]https://i1091.photobucket.com/albums/i382/MaynorSmit/DSCF1864.jpg[/img] [img]https://i1091.photobucket.com/albums/i382/MaynorSmit/DSCF1870.jpg[/img]

[applestar]

Oh gosh, I re-read my post and it DOES sound like I said the red blobs are aphids.
No, no. the red blobs are part of the structure of the leaves.

Sorry for the confusion.

[GojiBerryCrab]

Ah, thanks. So the blobs are part of the tree!
Now I'll just have to get rid of the ants

[JONA878]

Hi
I don't believe they are Aphids GojiBeryCrab.......that's one hell of a mouthfull.. ....but I also don't think it is a natural structure.
I think they may be small gauls produced by the plant as a result of either virus from aphid bite or a gaul wasp of some sort.
Either could induce the plant to weep which would attract ants to the liquid exuded.
I could be wrong....probably am.... but either way.. I don't believe they threaten your tree at all.

[!potatoes!]

sweet cherries grow EXACTLY those structures, just where the leafstem meets the broad part of the leaf. they're extra-floral nectaries, and since they do produce nectar, they are very popular with ants. I doubt the ants are doing any damage.

oh. prunus avium. that IS a kind of sweet cherry. close to plum, but not one. natural structures, though.

[Kisal]

Those "blobs" are called extra-floral nectaries. If you watch, you should see honeybees working them. They do on my cherry tree, anyway.

[JONA878]

Yup...got that one way wrong.
Filed away for the future.

[Kisal]

I think the second question I asked when I joined this site was for an ID of those "things" on my cherry tree. I don't recall ever getting an answer. After much research, I finally discovered what they were, so now, I share the info every time I get a chance.