Root borers are notorious pests, but are they dangerous to humans? For example, is broad necked root borer poisonous? Let’s find out.
Seeing scary-looking black beetles at the base of your plants? Despite the appearance, it could be a very harmless root borer!
Black in color with a thick head and strong jaws in front, the Broad-necked Root Borer looks scary both as a larva and an adult.
However, they are not poisonous and cannot harm humans or pets.
Though the same cannot be said for plants. Infected trees can die if they’re young.
Even older, healthy trees can end up with weakened roots, making them liable to falling over.
What Is The Broad Necked Root Borer?
Discovered in 1773, the Broad Necked Root Borer is a type of longhorn beetle.
Their common habitat includes parts of North America, and they’re widely considered pests, both in larval and adult form.
They’re found all the way from Quebec in Canada, through North Carolina to Arkansas in the South.
They look quite similar to the Black Caterpillar Hunter but have a thicker neck which helps distinguish them.
What Does It Look Like?
The Prionus laticollis is dark brown to black in color with a hard body protected by an exoskeleton.
The underside or belly is yellow in color.
When compared to other longhorn beetles, the broad-necked root borer has a much thicker neck covered with spikes – giving them their name.
Female broad-necked root borers are almost twice the size of males, and this makes it impossible for them to fly, despite having wings.
Males are smaller in size and can fly.
Females also have a long thing, an ovipositor at the end, which helps them deposit eggs within the ground.
Both sexes have black mandibles, with the males having the larger ones that they use in territorial fights.
As with other beetles, the root borer is quite efficient at burrowing at the base of trees and shrubs – especially oak.
Are They Dangerous To Humans?
Despite their scary look, root borers are not poisonous. They cannot harm humans or pets – even if your pet happens to ingest them.
However, they do have strong burrowing mandibles which can deliver a strong bite.
While I don’t suggest it, you can pick them up gently and throw them away. The beetles do not usually bite unless they are attacked.
Do They Bite or Sting?
They cannot bite or sting. While the female might look like she has a sting – it is actually an ovipositor.
The ovipositor is a thin, needle-like organ that protrudes from the rear of the female.
This helps them to lay eggs deep within the ground. They then use the ovipositor to cover the eggs with more soil by moving them up and down.
Are They Poisonous/Venomous?
Root borers do not possess any venom. Hence, they are not poisonous.
Even if this beetle does end up biting you, you will only suffer from temporary local inflammation.
It is rare for them to attack or bite humans, as most of their aggression is reserved for other beetles.
What Is Their Lifecycle?
The female will generally lay clutches of eggs at the base of trees and shrubs.
Generally, each clutch contains groups of two to three eggs. After covering the eggs with soil again, both sexes leave.
The eggs turn from sharp white to pale yellow and eventually a washed-out shade of pink.
Finally, just before the larvae hatch, the eggs take on an ivory shade.
The larvae chew their way out through the egg and can be as large as 3.5 inches.
They have well-developed mandibles that they use to burrow out of the soil and feed on bark or soft, dead wood.
Eventually, they start burrowing through roots, damaging crops they come in contact with.
After this, the larvae enter into a pupal stage from which adult beetles emerge.
The adults feed on tree foliage and fruits. The entire process can take upto three years.
What Do Broad Necked Root Borers Eat?
Larvae start by feeding on softwood and eventually start eating the roots of a variety of trees – even those of older, larger plants.
Adults eat foliage, fruits, and dark and internal plant tissue.
Due to their voracious appetite, the broad-necked root borer is a huge pest for gardens and agricultural lands.
Some common fruit trees they attack are peaches, apples, grapes, and other deciduous softwood trees.
Where Do They Live?
Generally, the larvae can be found at the base of deciduous trees, where they feed on shoots and roots.
Adults also mostly hide within plant debris, at the base of shrubs, or within their food source.
Frequently Asked Questions
What does broad-necked root borer eat?
The broad-necked root borer is an invasive beetle species native to North America.
Its larvae feed on the roots of trees, such as maple, oak, and beech, as well as any other woody material.
Adult beetles eat the foliage and can cause extensive damage to vegetation. They have also been known to vector a number of diseases that further damage plants.
In order to control this species, it is important to plow deeply in order to reach their larvae so they can be destroyed by pesticides or biological control agents.
Do broad-necked root borers fly?
Broad-necked root borers are large beetles; however, although they have wings, they do not fly.
These beetles spend their life cycle below the soil, having very brief interactions with sunlight during adult emergence and mating activities.
By living in the ground, Broad-necked Root Borers are capable of causing severe damage to crops and trees.
They were among the first identified serious pests of sweet potatoes in North America and remain a major pest in some areas still today.
Do wood borers bite humans?
Wood borers do not bite humans, as they are insect larvae that feed on wood.
However, adult wood borers do have the capability to bite humans if one gets too close to the adults or attempts to handle them.
Therefore, it is important to be careful when dealing with wood materials that may have been infected with wood borers.
Additionally, the droppings of these pests can cause respiratory problems in humans if one is exposed to them for extended periods of time.
What is the best remedy against borers?
The best remedy against borers is to practice preventive measures and intervene quickly when they are identified.
Prevention means regularly examining plants for signs of borer damage and removal of weakened or dead stems and branches, as these can act as a source of infestation.
If borers are found, promptly prune the stem or branch and twig several inches back past any visible signs or activity.
In some cases, spot treatments with insecticides may be necessary for severe infestations.
Finally, keep irrigation up-to-date to keep plants healthy; this reduces their susceptibility to borer attacks.
Wrap Up
While one can use insecticide to get rid of them, it’s best to prevent their growth itself by keeping your plant base clean and debris-free.
This will give them less shelter and egg-laying zones and make them more visible to possible predators.
Another alternative is to paint the bottom 2 feet of trees with latex paint.
If you have an infestation, it’s best to consult degreed professionals for help. Thank you for reading.
