For non-aggressive wasps I've had great luck spraying nests with this Spectracide wasp remover in the evening. For a nest up high in an eave, soffit, or tree, this Gotcha pole adapter clamps onto the can so you can spray from the end of an extension pole and treat the nest from 10+ feet away instead of standing right under it. And for anything aggressive I wear this ridiculous-looking upper torso beekeeping suit and keep my distance. It seems silly, but trust me, I learned the hard way.
If you have ever peered into an exposed wasp nest or knocked one down during the off-season, you may have noticed rows of small, pale, grub-like creatures tucked into the papery cells. These are wasp larvae, the immature feeding stage of a wasp’s life. Understanding what wasp larvae are, what they look like, what they eat, and what their presence means can help homeowners respond calmly and safely when they encounter them.
This guide focuses specifically on the larval stage of wasp development. If you are trying to identify the adult insects flying around your property, our complete wasp identification guide is a better starting point.
Wasp larvae are the second stage in a wasp’s life cycle. Wasps undergo complete metamorphosis, meaning they pass through four distinct stages: egg, larva, pupa, and adult. The larva is the growing, feeding stage, roughly equivalent to a caterpillar in a butterfly’s life cycle.
The larval stage exists for one purpose: to eat and grow. A wasp larva does almost nothing else. It cannot fly, walk, sting, or leave its cell. It simply remains in place inside the nest, is fed by adult workers, and steadily grows until it is ready to transform into a pupa and then an adult wasp.
For social wasps such as paper wasps, yellowjackets, and hornets, the larvae develop inside the familiar papery nest. For solitary wasps such as mud daubers and digger wasps, larvae develop inside mud tubes, underground burrows, or other individual chambers stocked with food by a single female.
Wasp larvae are small, soft-bodied, and pale. Knowing what they look like helps you confirm what you are dealing with and distinguish them from other insect larvae.
Key features of wasp larvae include:
When a nest cell is capped with a white, silky, dome-shaped covering, the larva inside has stopped feeding and entered the pupal stage. Those capped cells are no longer larvae but pupae transforming into adults.
It is easy to mistake wasp larvae for the grubs of beetles, fly maggots, or moth larvae. The most reliable clue is context: if the pale grubs are sitting in the cells of a papery, hexagonal nest, a mud tube, or a sealed burrow, they are almost certainly wasp larvae.
The diet of wasp larvae is one of the most surprising and important parts of wasp biology, and it differs sharply from what adult wasps eat.
Wasp larvae are carnivorous. To build the tissue they need to grow, they require a high-protein diet. Adult workers hunt down prey such as caterpillars, flies, spiders, aphids, and other soft-bodied insects. They chew this prey into a soft, manageable paste and feed it directly to the larvae in the nest.
This is precisely why social wasps are considered beneficial in gardens and on farms. A single thriving paper wasp or yellowjacket colony can remove thousands of pest insects over a season, all to feed its hungry larvae. If you want to understand the broader role of wasp feeding, see our guide on what wasps eat.
Adult wasps, by contrast, cannot digest solid prey well. They feed mainly on sugars, including flower nectar, ripe fruit, plant sap, and the sweet drinks and foods at your summer picnic. This split diet, protein for the young and sugar for the adults, drives much of wasp behavior.
Here is the clever part. When an adult worker feeds prey to a larva, the larva responds by producing a sugary, nutrient-rich secretion that the adult drinks. This exchange, called trophallaxis, gives the adult a reward and helps keep the colony functioning as a unit.
It also explains a seasonal change in wasp behavior. In late summer and fall, the colony stops raising new young. Once the larvae are gone, adults lose their easy supply of sweet larval secretions and become far more interested in finding sugar elsewhere, which is why wasps seem so much more aggressive around food and drinks in autumn.
No. Wasp larvae cannot sting or bite people. A wasp’s stinger is a modified egg-laying organ that only develops in adult females, and larvae do not possess one. Their small jaws are used only to accept food, not to defend themselves.
This means the larvae themselves are harmless to handle. The real danger is the adult wasps guarding them. A nest full of larvae is a nest the colony will defend aggressively. Disturbing a nest to get a look at the larvae can provoke dozens of adult wasps to sting in defense. If you are stung during such an encounter, our wasp sting treatment guide explains how to respond.
The journey from egg to adult wasp is surprisingly quick during the warm months.
The entire cycle from egg to adult often takes only three to four weeks in peak summer, which is how a small spring nest can grow into a large colony by late summer. Temperature plays a major role: development slows considerably in cooler weather. For more on the overall timeline, see how long wasps live.
Not all wasp larvae grow up the same way. The two broad groups handle their young very differently.
Paper wasps, yellowjackets, and hornets are social. Their larvae are raised communally inside a shared nest and are fed continuously by a rotating crew of adult workers. Because the colony grows throughout the season, a mature social nest can contain hundreds or even thousands of larvae and pupae at once.
Mud daubers, digger wasps, and cicada killers are solitary. A single female builds and provisions individual cells, then leaves. Instead of feeding her young day by day, she stocks each cell with paralyzed prey, such as spiders for mud daubers or cicadas for cicada killers, lays an egg, and seals the chamber. The larva hatches and eats the stored, still-living prey until it is ready to pupate. The mother never returns, and the larva develops entirely on its own.
This difference matters for homeowners. A solitary wasp’s nest, such as a mud dauber tube, contains only a few larvae and is defended by a non-aggressive lone female. A social wasp nest contains far more larvae and a large defensive workforce.
Finding wasp larvae almost always means there is, or recently was, an active nest nearby. What you should do depends on where you find them.
The larvae themselves carry no venom and cannot harm you. They are not known to spread disease to humans. The concern is never the grubs but the adults defending them and the structural nest they occupy. A nest in a wall void or attic should be addressed because the colony will continue to grow as more larvae mature into workers.
If you discover an active nest full of larvae in a high-traffic area, inside a wall or attic, or anywhere near people with known sting allergies, professional removal is the safest choice. Large social colonies in particular can react violently when disturbed, and a nest hidden inside a structure is difficult to treat thoroughly on your own. A licensed pest control professional can remove the nest, larvae and all, while minimizing the risk of stings.
Wasp larvae are the quiet, hungry engine of every wasp colony. Pale, legless, and confined to their cells, they cannot sting or bite, and on their own they are completely harmless. Their real significance is what they tell you: where there are larvae, there is a nest, and where there is a nest, there are adult wasps prepared to defend it. By recognizing wasp larvae, understanding their protein-driven diet, and knowing how quickly they mature into adults, homeowners can make smarter, safer decisions about whether to leave a nest alone or have it removed.
For a broader overview of the species you might encounter, return to our complete wasp identification guide, and if you found these grubs while investigating a nest, our baby wasp guide covers the full immature stage in additional detail.