Stink Bug vs Squash Bug: Similarities and Differences

Stink bugs and Squash bugs are some of the most common invasive species in gardens. Both have similar feeding habits and to an extent, both look quite similar.

Telling the difference between these species isn’t easy. Both can invade gardens and they can impact the growth of various types of squash such as zucchini.

However, there are ways to tell these species apart.

What are Stink bugs?

Stink bugs are a specie of flattened bugs with shield-like body size. They grow up to 1 inch and they’re mainly known for being as long as they are wide.

There are various species of Stink bugs but many come in a brown or brown-gray color.

An adult brown marmorated stink bug

Stink bugs eat the liquid of fruits and vegetables.

They eat peas and beans. But they also go for fruits they find in the garden such as apples and peaches.

Stink bugs are further damaging fruits and vegetables by spreading diseases that stung plant growth.

These bugs are known for spreading yeast-spot diseases which may affect the health of fruits and vegetables.

What are Squash bugs?

An adult squash bug

Squash bugs are known to have a similar size to Stink bugs. However, Squash bugs are primarily known for feeding on squash, pumpkin, and other squash species.

These bugs are mostly brown or gray, similar to many species of Stink bugs. They also have wings that cover their shield-shaped bodies.

Squash bugs rarely use their wings as they prefer to rely on their legs to move from one plant to another.

Why Stink bugs are often confused with Squash bugs?

Stink bugs and Squash bugs have both been called the Shield bug based on the shape of their body. However, these bugs are different species.

They have differences and similarities. Here’s what makes them hard to distinguish.

Similar foul odor

Stink Bugs and Squash bugs both release a similar foul odor. This is a bad smell they are known to release when handled or threatened.

Stink bugs and Squash bugs have a limited number of predators due to this innate ability. They release this foul smell which makes them taste bad but which keeps them safe and in high numbers in gardens, farms, and on crops.

Hard shells shaped like a shield

Both Stink bugs and Squash bugs are known for their hard shells. This has a defensive role against predators. Most importantly, both species have a shield-like body shape which confuses precise species identification.

Similar brown or gray color

Stink bugs and Squash bugs come in many colors such as yellow, green, stripes, and marked bodies. However, brown and gray coloring is very common in both species which causes further confusion.

Similar size

Both species are known to be small as they grow up to 1 inch. They are seen as small bugs but wide bugs given they have a wide body (except the head).

3 pairs of legs

Both species are known for having 3 pairs of legs. With 6 legs and a similar body shape, these bugs are routinely misidentified. Even their antennas look similar as they can be colored in the same color as the rest of the body.

Both species are shield-shaped and they might also come in a similar brown or gray color. Stink bugs are known for being larger as they’re wider.

Both species can be detrimental. Squash bugs are considered less detrimental as they only impact pumpkin, squash, and melon. These are all part of the cucurbit family.

Squash bug vs Stink Bug: 5 major differences

While partially similar, these species are different even in size. The most obvious differences between Stink bugs and Squash bugs can be summarized as follows.

1. Stink bugs have wider bodies

Subtle differences in body shape can be seen between these species. Stink bugs are known for having a wider body, especially towards the tip of the abdomen.

Squash bugs have a more oval abdomen tip with an elongated profile. This makes it appear narrower.

2. Squash bugs have a rounder shape

Stink bugs and Stink bugs are both known for having a shield-like body shape. Of the two species, the Squash bug looks the least like a shield due to its more elongated body.

A rounder body shape is characteristic of Squash bugs. Otherwise, both species appear to have a flattened body.

3. Squash bugs are slightly shorter

Squash bugs are known to have a common size of about half an inch. Stink bugs are known to grow to almost a full inch. This is why Stink bugs may appear larger, especially since they’re also wider.

However, size alone is not a sufficient indicator to tell these species apart as it varies considerably.

Access to food can limit or enhance the size of a bug. Both Squash bugs and Stink bugs are known for growing to a smaller size compared to their maximum recorded size even when growing on crops.

As a result, some Stink bugs may be larger than Squash bugs and some Squash bugs might be larger than Stink bugs depending on their age and environment.

4. Squash bugs only eat squash

Squash bugs eat all types of squash and pumpkin. They’re mostly interested in leaves, wines, and the juice of the fruit.

Apart from them eating these parts of the squash, their saliva also impacts the squash. The saliva of Squash bugs is toxic. The plant eventually dies.

5. Stink bugs don’t eat cucurbits

Stink bugs aren’t known for eating squash and pumpkin. This is the easiest method of separating the species as Stink bugs aren’t seen on the pumpkin.

Stink bugs prefer tomatoes and other vegetables. The place where you see these bugs can help you quickly identify the species without further looking at other physical traits.

Summary

Stink bugs and Squash bugs are very similar species that are mostly seen in the garden.

These bugs can also fly indoors, especially when the temperature starts to drop in the fall. They might also make their way indoors attracted to artificial light.

Both species are now home pests as they only eat fruits and vegetables from the garden. However, they are found in different parts of the garden.

As the name suggests, the Squash bug is mostly seen on cucurbits and in the garden or in areas where cucurbits grow.

Stink bugs have a wider habitat as they don’t depend on a single species of vegetables and they might also eat fruit. Both Squash bugs and Stink bugs overwinter in sheltered locations such as under rocks and leaves or indoors for better protection against cold weather.

Further Reading: