Hawk moth (sphinx) caterpillar
The biggest caterpillar you will find on a sesame plant — which is exactly what makes it one of the easiest to catch before it strips the leaves.
- Pest type
- Large defoliating caterpillar
- Attacks
- Leaves (whole-plant defoliation)
- Worst in
- Patchy, sudden outbreaks
- Main risk
- Rapid leaf loss on individual plants
Overview
The hawk moth, or sphinx caterpillar, is a large green caterpillar with a visible tail-horn near its rear end, much bigger and more conspicuous than the other, smaller sesame caterpillar pests. It feeds on leaves and can strip an individual plant rapidly if left alone.
Because of its size, it is one of the easiest field pests to spot by eye during a routine walk through the crop, and hand-picking is a genuinely practical control — a few large caterpillars removed by hand often solves the problem on its own before it needs a spray.
How to identify it
- Large green caterpillars with a visible tail-horn near the rear end — much bigger and more conspicuous than most other sesame caterpillar pests.
- Plants stripped of leaves rapidly, often in scattered individual plants or small patches rather than evenly across the field.
- Because of its size, this caterpillar is one of the easiest crop pests to spot by eye during a routine field walk.
The damage it does
- Heavy leaf loss on individual plants, which cuts the plant’s ability to fill pods and seed properly.
- Usually patchy across the field, but damage on an affected plant can be sudden and severe.
- A few large caterpillars can strip a plant of most of its leaves within days if left alone.
When to act
- Walk the field regularly and look for stripped or partly stripped plants — the caterpillars themselves are large and easy to confirm once you spot the damage.
- Act while numbers are still low, since hand-picking is genuinely practical for this pest given how large and visible it is.
- Treat only the affected patches rather than the whole field where the outbreak is localised.
Organic & cultural control
- Hand-pick the caterpillars — their large size makes them easy to catch and this is often enough to control a light infestation on its own.
- Check plants regularly enough to catch caterpillars while they are still small and before they have stripped much foliage.
- Encouraging birds and natural predators in the field helps keep numbers down between outbreaks.
Chemical control
- Spot-spray a recommended insecticide only on affected patches if numbers are too high for hand-picking to keep up.
- Because the pest is usually patchy, a full-field spray is rarely necessary — treat the trouble spots instead.
- Confirm the current recommended product and dose for sesame with your local KVK.
Crops most at risk
Where this problem is called out in our crop guides — open a crop for the full package of practices.
Frequently asked questions
I found a large green caterpillar with a horn-like tail on my sesame plant. What is it, and should I worry?
That is the hawk moth (sphinx) caterpillar. It is large and easy to spot, and though it can strip a plant of leaves quickly, hand-picking usually controls it well since there are rarely huge numbers of them.
Do I need to spray my whole field for this pest?
Usually not. This caterpillar tends to cause patchy, localised damage rather than an even field-wide attack, so spot-checking and hand-picking, with a spot-spray only on badly affected patches, is normally enough.
How is this different from other sesame caterpillars?
It is much larger and has a distinctive tail-horn, unlike the smaller leaf webber or gall fly pests of sesame. Its size is actually an advantage for you — it is one of the easiest sesame pests to spot and hand-pick before it causes much damage.
Symptoms and control measures follow ICAR, KVK and state agricultural-university package-of-practices; any named chemical is a registered use. Always read the product label and confirm the dose for your crop and zone. editorial policy.