Hey all, Im in Oakland ca zone 9 and having problems with scales, and of course ants on a young dwarf lime tree. Looking for alternatives to buying something. Any home remedies for scale treatment? Is the treatment different depending on what type of scales they are?
I've noticed some scale insects (with their attendant ants) on our apricot trees for the past few summers, so I asked about it here last year. The advice boiled down to this: If it's not causing serious damage to the tree, let it be as part of your ecosystem, and hope it stays within reasonable limits. Scales suck sap and in large numbers can weaken the plant, but don't directly damage the fruit.
A dwarf lime tree is small enough for you to just pore over it closely and nudge the scales off with a twig. I find myself doing that sometimes when I'm wandering among our apricot trees just kind of loving the trees. It wouldn't work on a large farm but for a home garden can help. Our trees are tall enough that now I can't reach the upper branches, but the scales haven't had a population explosion as I feared so I guess it's alright.
I saw online that if you put a tanglefoot (sticky fly-paper type surface) collar around the trunk of the tree, the ants can't walk up to tend to the scales or aphids so those die. I don't know if that is true, since scales and aphids seem to be sucking the sap where they are. Are the ants helping the suckers or only milking them? Of course this also depends on your tree standing free of other paths for the ants.
Works at a residential alternative high school in the Himalayas SECMOL.org . "Back home" is Cape Cod, E Coast USA.
Location: Oakland, CA zone 8/9b
posted 5 years ago
Thank you so much for your response. I should have mentioned that last summer all of my fruit dropped off when it was still very small. I didn't think so at the time, but after researching scales a little more I believe it was the cause. At that point I thought I had ants eating aphids. I guess I will try and remove the scales by hand and try and eradicate the ant problem? I have tried many natural remedies to get rid of the ants, but they keep coming back.
There's only one road for ants climbing up a tree -- the trunk. I make a paste of vegetable oil and diatomaceous earth and paint this low around the trunk. Not going to have any ants climbing through that!
Then what to do about the ants and the insects they are tending up in the leaves? A pressure nozzle on a garden hose, set so it will blast the leaves yet not rip them off, will remove a large number of the infernal pests. I have one plum tree they like to go after. The other two they leave alone, but the one in the middle must have some ant/aphid attractant to it. After a trunk painting and a vigorous shower, the tree is left in peace.
Oh, and citrus trees always have a big immature fruit drop, usually around June or so. If you are left with a paltry amount ripening in September, then you should be concerned.
gardener & author
Location: Ladakh, Indian Himalayas at 10,500 feet, zone 5
I too have had problems with scale insects on my citrus . Since I remove them inside in the winter I have to use a top secret very powerful insecticide . Its called WUL one drop in a litre of water sprayed on the plant at weekly intervals while the infection lasts . Outside in the summer I find nature takes its course and the lady birds do the biz if I stand the plants in water the ants cannot get at them.
Keep it quiet but WUL stands for washing up liquid
Living in Anjou , France,
For the many not for the few