Divisi
Citrus psyllid
Trioza erytreae · Insect
Photo: Tony Rebelo (iNaturalist) · CC BY-SA 4.0
The African citrus psyllid (Trioza erytreae) is a tiny sap-sucking insect — about the size of a grain of rice — that breeds only on the soft new leaves (the flush) of citrus: orange, lemon and lime. Its own feeding does little lasting harm; the real danger is that it is the African carrier of citrus greening (also called Huanglongbing, or HLB), an incurable bacterial disease that slowly starves and kills citrus trees. It thrives in cool, moist highland country, and wherever it meets fresh flush it can quietly turn a healthy orchard into a dying one.
Kristopher Brand (iNaturalist) · CC0 1.0 
Florida Division of Plant Industry Archive, Florida Department of Agriculture and Consumer Services, Bugwood.org · CC BY 3.0 us
Why it matters
On its own, this little insect barely dents your trees. The real danger is what it carries: citrus greening, an incurable disease it passes from tree to tree the way a mosquito passes malaria. Once greening takes hold, your fruit turns small, lopsided and bitter, branches die back, and a badly hit orchard can lose up to 40% of its harvest before the trees slowly die. There is no medicine — you cannot cure a sick tree, you can only stop healthy ones from being infected — which is why catching the insect early, on the new flush (the soft young leaves), is everything.
When to act
Any psyllids or open-pit galls found on new flush warrant action because of the greening (HLB) disease risk; there is effectively zero tolerance near young trees.
This guidance is general, compiled from published agronomic references including FAO and CABI. Thresholds and timing shift with your crop, your variety and the season.
In much of the region a spray is simply called mushonga — medicine. But a chemical group you cannot name is one you cannot rotate, and a product you did not write down has no pre-harvest interval you can observe. Mushonga, and other farming words →
The full citrus psyllid field guide
- Identify it
- Scout for it
- Control it
13 field-guide sections in the app
The full guide to citrus psyllid — every symptom to check, how and when to walk your field looking for it, and the controls that actually work, ranked. Built into your crop plan, so you are told to look before it costs you a harvest.
Crops it affects
Frequently asked questions
How do I identify citrus psyllid?
The first thing you notice is damage on the soft new growth — the tender, pale or reddish young leaves the tree keeps pushing out (the flush). The psyllid's feeding raises little cup- or crater-shaped bumps called pit galls, so the leaf looks like it has goose-bumps or blisters with an open pit underneath; the leaves also curl, pucker and yellow. A sticky honeydew (the insect's sugary droppings) coats the leaves and later turns black with sooty mould.
When should I take action against citrus psyllid?
Any psyllids or open-pit galls found on new flush warrant action because of the greening (HLB) disease risk; there is effectively zero tolerance near young trees.
How do I control citrus psyllid?
Start clean and stay clean — this is your strongest protection. Only plant certified disease-free nursery trees; greening most often arrives hidden inside infected young stock. Then walk your orchard, and any citrus next door, for sick trees (blotchy lopsided mottle, small bitter fruit, branch dieback) and remove and burn them promptly, along with any abandoned or neglected citrus nearby — every infected tree is a well the psyllids draw greening from and carry to your healthy trees. Where you can, push your trees to flush together in one short burst rather than a trickle all year, so the psyllid gets a smaller window to breed.
Which crops does citrus psyllid affect?
Among the crops covered here: Lemon, Lime.
Catch it before it costs you a harvest
Divisi builds scouting into your crop plan — it tells you when to walk your field, what to look for at that stage, and what to do when you find it. Free for farmers, works offline.
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