Lemon tree has white pods and black discoloration on branch
I noticed these unusual white "pods" on some of the branches of my lemon tree. There is also black substance on the branch along with these pods. Can you tell me what it is and how to get rid of it? Thanks.
Hi Roman
It looks very much like Woolly Aphid or one of the scale bugs. They produce the waxy white deposit to give them protection.If you rub the White stuff off gently you will find the aphid or scale bug beneath.
The black deposit is the sugar deposit they leave as they feed...this quickly grows a mould that is the black you see.
If you only have a small amount wipe them off with a cloth and a little mentholated spirit.
It looks very much like Woolly Aphid or one of the scale bugs. They produce the waxy white deposit to give them protection.If you rub the White stuff off gently you will find the aphid or scale bug beneath.
The black deposit is the sugar deposit they leave as they feed...this quickly grows a mould that is the black you see.
If you only have a small amount wipe them off with a cloth and a little mentholated spirit.
Hi Jona. Thank you for your input. I tried rubbing one of these pods off and there was no aphid underneath. I googled the wooly amphid for photos and it doesn't really look like that. These are cylinder shaped with grooves running down all around. Any other suggestions? I thought they could be mealybugs but again doesn't really look like that. I sprayed with a mixture of water, little dish washing soap and alcohol. Hopefully it helps.
- GardeningCook
- Greener Thumb
- Posts: 787
- Joined: Wed Apr 29, 2015 8:35 pm
- Location: Upper Piedmont area of Virginia, Zone 7a
What you have there is an extremely nasty infestation of Mealybugs. And yes, they do have "grooves" on them, they do attract "Black Sooty Mold", & they do LOVE citrus plants. Can be difficult to eradicate completely, especially at this stage, but it's worth trying.
Here's one link on them, but there are quite a few others online that you may want to read before deciding your best course of action.
https://homeguides.sfgate.com/mealy-bugs ... 26552.html
Here's one link on them, but there are quite a few others online that you may want to read before deciding your best course of action.
https://homeguides.sfgate.com/mealy-bugs ... 26552.html
- rainbowgardener
- Super Green Thumb
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- Joined: Sun Feb 15, 2009 6:04 pm
- Location: TN/GA 7b
Yes, I agree, scale insect. There are a zillion varieties of them in different sizes, shapes, colors. This is just one sample:

https://www.iranicaonline.org/uploads/fi ... fig_5a.jpg
In general, in general they just look like bumps on your branch, usually oval-ish, and they are immobile. You won't find an aphid or anything when you lift the bump, because (oddly enough) the bump IS the insect.
They do excrete a clear, sweet, sticky substance called honeydew, which then gets colonized by the black sooty mold.

https://www.iranicaonline.org/uploads/fi ... fig_5a.jpg
In general, in general they just look like bumps on your branch, usually oval-ish, and they are immobile. You won't find an aphid or anything when you lift the bump, because (oddly enough) the bump IS the insect.
They do excrete a clear, sweet, sticky substance called honeydew, which then gets colonized by the black sooty mold.
I thought they looked more like Cottony cushion scale. Scales are common pests of citrus trees. The black stuff is probably sooty mold that grows on the sap that the scales are sucking out of the tree. The mold grows on the sap.
The mold itself will go away once the scales are taken care of.
Treat the area for ants by putting out ant baits. Terro works on sweet eating ants.
Here is another ant bait recipe: Works for sweet and grease eating ants. measuring spoons, cups and containers should be dedicated for this task just in case. I even have a jar of goober labeled just to make bait.
Mix three parts peanut butter with two parts jelly and add one tablespoon of boric acid per six ounces of mix. Place the bait on pieces of paper so stuff it into large straws and place where you see the ants foraging. Again keep out of the reach of pets and children.
Ants will farm aphids and scale and protect them from their predators.
Scale adults are hard to kill, horticultural oils work better than soap. I use a soft brush and a smaller toothbrush and alcohol to scrub them off the branches and leaves. Then hose off with water. Even if scale is killed by the oil, the shell will remain on the branch. Once the scales are dead, there will be no sap for the mold to live on and it can be washed off with water.
https://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7410.html
The mold itself will go away once the scales are taken care of.
Treat the area for ants by putting out ant baits. Terro works on sweet eating ants.
Here is another ant bait recipe: Works for sweet and grease eating ants. measuring spoons, cups and containers should be dedicated for this task just in case. I even have a jar of goober labeled just to make bait.
Mix three parts peanut butter with two parts jelly and add one tablespoon of boric acid per six ounces of mix. Place the bait on pieces of paper so stuff it into large straws and place where you see the ants foraging. Again keep out of the reach of pets and children.
Ants will farm aphids and scale and protect them from their predators.
Scale adults are hard to kill, horticultural oils work better than soap. I use a soft brush and a smaller toothbrush and alcohol to scrub them off the branches and leaves. Then hose off with water. Even if scale is killed by the oil, the shell will remain on the branch. Once the scales are dead, there will be no sap for the mold to live on and it can be washed off with water.
https://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7410.html