Shisham defoliator
Caterpillars of two moths that feed on sheesham leaves through the growing season, capable of periodic outbreaks that thin the canopy of trees already at risk from wilt.
- Pest
- Caterpillars (Plecoptera reflexa; Dichomeris eridantis)
- Feeds on
- Leaves through the growing season
- Pattern
- Periodic outbreaks; leaf webber range expanding in hill states
- Main risk
- Slowed growth; added stress that can worsen wilt vulnerability
Overview
The shisham defoliator, Plecoptera reflexa, is the main leaf-feeding caterpillar pest of sheesham across India, capable of periodic outbreaks that significantly thin a tree's canopy. A secondary pest, the shisham leaf webber (Dichomeris eridantis), webs leaves together and feeds within the shelter; research modelling suggests its range is expanding in hill states such as Uttarakhand as the climate warms.
Neither pest is usually as immediately dramatic as an outbreak on poplar or teak, but repeated heavy defoliation matters more on sheesham than it might elsewhere, because the resulting stress can compound a young tree's vulnerability to the far more serious Fusarium wilt/dieback disease that the crop is already prone to.
How to identify it
- Plecoptera reflexa caterpillars feeding openly on leaves through the growing season, capable of stripping significant canopy in an outbreak.
- Dichomeris eridantis caterpillars webbing leaves together and feeding from within the shelter — look for small silk-bound clusters of leaves.
- Periodic population outbreaks rather than constant low-level feeding.
What causes it and when
- Two distinct moths, active through the growing season, found throughout sheesham-growing areas of India.
- The leaf webber's range is documented as expanding in hill states like Uttarakhand as the climate warms, so it is worth watching even outside its traditional range.
Organic and biological control
- Conserve natural predators and parasitoids rather than routine broad-spectrum spraying.
- Hand-collect caterpillars or remove webbed leaf clusters from young trees where an outbreak is small and localised.
Chemical control
- A CIB&RC-registered contact insecticide spot-sprayed at the first sign of a heavy outbreak on young, high-value plantings; confirm the current product with your state forest department or KVK.
- Light, routine defoliation on established trees rarely needs chemical treatment — reserve spraying for a genuine, damaging outbreak.
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
Does defoliation make my sheesham trees more likely to get wilt disease?
It can contribute. Repeated heavy defoliation adds stress to a tree, and water/general stress is one of the documented factors that makes sheesham more vulnerable to Fusarium wilt/dieback. It is not the primary trigger — a fluctuating water table is — but keeping defoliator and leaf webber populations in check is still worth doing on a block already at risk from wilt, rather than treating the two problems as unrelated.
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.