Plant root pests are often harder to spot than other garden pests, due to their tendency to hide away under the surface of the soil. Unfortunately, they can do extensive damage to the plants they infest, and root eating bugs can be a disaster for your garden.
Learning how to successfully identify root eating pests is essential for effective control. If you suspect you have an infestation, the first thing to do is to work out exactly what you’re dealing with. The most common types of root pests include root mealybugs, root aphids, fungus gnat larvae, root maggots, and root weevils.
How can you tell if you have plant root pests?
Wilting leaves, stunted growth, drooping flowers, discoloration, and general poor health are all textbook examples of the damage to plants caused by root eating pests.
Keep in mind!
However, as the symptoms of plant root pests often mimic those of other plant diseases, the true culprits often hide away unnoticed for months.
If your garden is suffering and you’re not sure why try digging around in the soil at the base of your plants. If you find an unusually high number of insects and bugs crawling around down there, there’s a good chance your blooms are under attack from plant root pests.
Identifying these pests correctly is an essential first step for successful extermination. So, what are the most common types of plant root pests, and how can you tell them apart from one another?
What are the most common types of plant root pests?
- What are they? Root mealybugs are a type of mealybug that feeds on the roots of plants. These soft-bodied, sucking insects prefer to hang out beneath the soil surface and can, therefore, go undetected for long periods of time. Like above-ground mealybugs, they secrete wax, which gives them a white, cottony appearance. Plants with root mealybug infestations will look generally unwell and may have stunted growth.
- Identification: The main difference between mealybugs and root mealybugs is which parts of the plant they inhabit. Whereas mealybugs are usually found on the stems and leaves of plants, root mealybugs lurk underground in the root network of the plant. If your pot plants are looking droopy, take them out of the pot and examine the root system for the distinctive white, waxy substance that indicates the presence of root mealybugs
- What are they? Root aphids are closely related to aphids and live at or just above the soil line around plants. Their preferred habitat makes them harder to spot than other types of aphids, meaning a major infestation can develop right under your nose. These tiny, pear-shaped, sap-sucking insects can do significant damage to your plants by draining nutrients from the roots, but only if they are present in large numbers.
- Identification: Root aphids are similar in appearance to other types of aphids and are typically wingless, small, and yellow to gray-green in color. You can, however, tell them apart according to where they hang out on the plant. Root aphids congregate on or just below the soil level, whereas other varieties are found feeding on the leaves and stems of the plant. Plants with root aphid damage will often look generally unwell with wilted, yellowed or curled leaves and stunted growth.
Fungus gnat larvae
- What are they? Fungus gnats are tiny flies that lay their eggs in organic debris or moist soil, often around potted plants. When they hatch, the larvae burrow down into the surrounding soil to feast on decaying organic matter, fungi and root hairs.
- Identification: These legless, worm-like bugs have long, white or clear-ish bodies and shiny black heads.
When present in high numbers, or in especially moist conditions, fungus gnat larvae may leave slime-trails on the surrounding soil similar to those left by slugs and snails.
Large infestations of fungus gnat larvae can cause significant damage to plant roots, causing stunting and even death, particularly in young plants.
- What are they? Root maggots are a type of fly larvae that feed on the roots of plants. Once established they can be impossible to get rid of and can cause wilting, yellowing and stunted growth of host plants. Root maggots most often target young plants and are most active in the spring.
- Identification: Root maggots are yellowish-white, worm-like bugs that usually grow to around ¼ inch in length. They are legless with cylindrical bodies that taper at the head, and tunnel through roots and bulbs they feed off. Plants with root maggot infestations will often look wilted, yellowed and stunted, and heavily damaged plants may die early.
- What are they? Root weevils are a type of beetle that feeds on the roots of infested plants. Adult weevils feed on the foliage of plants in the summer and lay their eggs in the crown of the plant. Once they hatch, the weevil larvae burrow down into the soil to feast on the roots beneath. By doing this, weevil larvae are able to overwinter in your garden, emerging once more in spring to cause widespread damage to your plants.
- Identification: Root weevil larvae are white in pink in color with a distinctive brown head and a curved, legless body. They can reach up to 9mm in length. Plant wilting is your first indication of the presence of root weevils, as these bugs can completely devour roots and deprive the plant of water. Once the adults emerge, you’re likely to notice large chunks missing from the leaves of the plant as they start to much through the foliage.
Root maggots, fungus gnat larvae, root aphids, root mealybugs, and root weevils are all common plant root pests. Unlike other types of garden pest, these bugs don’t feed on foliage. Instead, they burrow down into the soil to chew through the roots of plants, causing widespread damage and depriving the plants of water and nutrients.
Root eating bugs usually cause an overall decline in plant health as a result, leading to wilting and yellowing leaves, stunted growth and even death.
Implementing an integrated pest management plan to keep root pests away from your plants is the best way to prevent an infestation, as these bugs can be tricky to get rid of once they’ve invaded your garden.