Wasp nests will eventually go away on their own, but how long they remain depends on the type of wasp and location of the nest. There are a few key factors that determine how quickly an abandoned wasp nest will disappear:
Wasp Nest Lifecycles
Different species of wasps have different nesting habits that affect how long their nests will persist:
- Paper wasps – Nests are only used for one season, then abandoned. Paper envelopes protecting the cells will weather and degrade within a few months after wasps leave.
- Yellowjackets – Nest envelopes are more durable and can persist for over a year if undisturbed. Nests are typically reused and expanded for multiple seasons.
- Hornets – Giant nests can be used for many years and tend to resist weathering. If not damaged, they can remain for several years after abandonment.
- Mud daubers – Mud nests are very durable and can last for years before crumbling away on their own.
So paper wasp nests will degrade the quickest, while hornet and mud dauber nests tend to linger much longer when abandoned.
Exposure to Elements
How quickly an abandoned nest decomposes also depends on how exposed it is to the elements:
- Nests protected under eaves or porch overhangs will break down slower.
- Nests hanging out in the open or exposed to rain, sun, and wind will degrade quicker.
- Nests attached to outdoor walls or fences will weather faster than those nested in trees or shrubs.
Greater exposure to things like sun, moisture, temperature extremes, and physical abrasion will help deteriorate fiber envelopes and nest materials faster.
Activity of Other Insects
Other insects can hasten the removal of an abandoned nest:
- Wood- or paper-feeding insects like termites and carpenter ants will damage nests.
- Saprophytic fungi and molds may grow on and decompose nest materials.
- Cocoons and larvae left in nests may attract scavengers looking for an easy protein source.
- Birds sometimes dismantle old nests to reuse the materials for their own nest building.
Any insect or animal activity that removes portions of the nest structure will accelerate the breakdown process.
Damage and Decay
Physical damage and general deterioration will also contribute to nest breakdown over time:
- Brittle nest envelopes crack and split open when subjected to weather extremes, allowing moisture inside.
- Alternating wet and dry, freezing and thawing conditions can accelerate breakdown of nest materials.
- Ultraviolet radiation from sunlight causes slow disintegration of paper envelopes.
- Rain and moisture soak into nests, promoting mold, mildew and rot.
- High winds may progressively rip pieces of the nest apart.
Even the most durable wasp nests will eventually succumb to seasonal weathering and decay over successive years.
Removal Factors
There are a few proactive steps that can be taken to encourage an abandoned nest to be removed more quickly:
- Knocking down the nest with a pole or water jet will accelerate dismantling.
- Removing the nest from its attachment point will expose it to faster degradation.
- Breaking the nest into smaller pieces will increase surface area and decomposition speed.
- Applying an insecticide will prevent wasps from reusing the nest.
- Setting out small pieces near ant or termite colonies may spur removals.
But keep in mind, physically removing nests, especially from higher locations, poses a risk of triggering aggressive defense behavior from any wasps still occupying the nest nearby.
Summary
On their own, the amount of time an abandoned wasp nest will remain intact can vary greatly depending on species, location, and exposure. Paper nests in the open may last only weeks or months. Giant hornet nests in protected areas can linger for many years. But all nests will eventually succumb to some combination of weathering, insect and animal activity, and simple decay. And if elimination is desired sooner, nests can be manually dismantled or removed from their anchor points and exposed to hasten the natural degradation process.
| Wasp Species | Typical Nest Persistence |
|---|---|
| Paper wasps | 2-4 months |
| Yellowjackets | 12-18 months |
| Hornets | 2-3 years |
| Mud daubers | 3-5 years |
Factors Accelerating Nest Breakdown
- Exposure to sun, rain, and wind
- Physical damage from weather extremes
- Foraging insects removing materials
- UV radiation degrading paper envelopes
- Alternating wet and dry conditions
- Mold, mildew, and rot
Removal Techniques
- Knock nest down with pole/water jet
- Remove nest from anchor point
- Break into smaller pieces
- Apply insecticide treatment
- Set out near ant/termite colonies
