What Do Grubs Look Like?

Grubs are the larval stage of various beetles. They have a very distinct appearance that makes them relatively easy to identify if you know what to look for:

• Color: They are typically creamy white with a slightly translucent body. Their hind end is usually a pale brown or tan.
• Shape: Grubs have a C-shaped curved body when at rest, which is one of their most recognizable features.
• Head and Legs: They have a small, brown head and three pairs of tiny legs near the front of their body.
• Size: Depending on their development stage, they can range from 1/4 inch to over 1 inch long. Younger grubs are very tiny and almost see-through, while mature ones are plumper and more noticeable.
• Texture: Their bodies are soft and slightly shiny.

Grubs are usually found just below the surface of soil, especially in lawns, gardens, or areas with rich vegetation. If you dig a little in the soil, particularly under damaged or browning grass, you’ll often spot them curled up.

Where Are Grubs Found?

Grubs are most commonly found just below the surface of soil, especially in areas that provide food and moisture. They prefer environments that make it easy for them to feed on roots and develop safely:

• Lawns and Turf: Grubs thrive in grassy areas, feeding on grass roots. Lawns that are well-watered or have thick, lush grass are prime targets. Damage signs include brown or spongy patches of grass that can be easily pulled up because the roots are eaten.
• Gardens and Flower Beds: They may be found in vegetable gardens, flower beds, or ornamental plant areas. They feed on the roots of plants like carrots, potatoes, or ornamental shrubs.
• Under Mulch or Leaf Litter: Grubs like moist, protected soil, so areas under mulch, compost, or thick leaf layers are common hiding spots.
• Lawns with Poor Drainage or Irrigation: Excessively wet or poorly draining soil attracts grubs, as they prefer soft, moist soil for burrowing and feeding.
• Near Trees and Shrubs: Some grubs, especially from scarab beetles, feed on the roots of shade trees, shrubs, or ornamental plants, so digging around the base of these plants may reveal them.

To check for grubs, lift a section of sod or dig 2–4 inches into the soil in suspected areas. If you find more than 5–10 grubs per square foot, it’s considered a heavy infestation that can seriously damage your lawn.

Grub Life Cycle

Grubs are the larval stage of beetles, and understanding their life cycle is key for effective control:

Egg Stage

• Timing: Late spring to early summer, depending on the beetle species.
• Where: Female beetles lay eggs in soil, usually in grassy areas.
• Appearance: Eggs are small, oval, and white or slightly yellowish.
• Duration: Eggs hatch in 1–3 weeks, depending on soil temperature and moisture.

Larval Stage (Grub Stage)

• Appearance: Creamy white, C-shaped, with a brown head and tiny legs.
• Feeding: Grubs feed on roots of grass and plants, which can cause lawn browning and plant stress.
• Growth: There are 3 larval instars (stages) as they grow.
• Timing: Most active in late summer through fall, when they burrow just below the soil surface.
• Overwintering: In colder regions, grubs burrow deeper into the soil during winter to avoid freezing.

Pupation Stage

• Timing: Late spring to early summer of the following year (for species with a one-year cycle).
• Process: Grubs stop feeding, move slightly deeper into the soil, and transform into pupae.
• Duration: Pupation usually takes 1–3 weeks, depending on species and temperature.

Adult Beetle Stage

• Appearance: Beetles vary by species (e.g., metallic green Japanese beetles, brown June beetles).
• Emergence: Adults emerge from the soil to mate and lay eggs, starting the cycle over.
• Damage: Adult beetles feed on leaves, flowers, and fruits, while grubs continue to damage roots.
• Lifespan: Adult beetles usually live for a few weeks to a few months, depending on species.
• Cycle Length: Most common lawn grubs follow a 1-year life cycle, but some species can take 2–3 years to complete their development.