Q: What are grubs and chinch bugs?

A:  Grubs and chinch bugs are insects that can cause damage to the roots, crowns or blades of your urban lawn depending upon the lifecycle stage of the insect, time of year and quality of the lawn. 

get rid of grubs naturallyUsually the damage is seen as a dying area of grass with characteristic brown patches.  It is very important to diagnose the problem accurately since dog spots, over fertilization and diseases can all create the tell-tale brown patches. 

Identifying the insect and the damage it is doing is important before deciding upon a specific course of action.

Grub is a term used most often to refer to the larval stage of one of three beetle species:  the European chafer, June beetle and Japanese beetle.  It is in the grub stage that these insects do the most damage by feeding on grass roots causing the grass to die. Because the grubs have destroyed the roots the grass pulls back easily. 

The grubs of all these beetles appear as white, C-shaped larva with tan heads and six legs.  Depending upon the species of beetle, the grubs most actively feed on grass roots in the fall and to a lesser degree in the spring.  Animals digging in search of the grubs to eat can also damage your lawn. 

The defense against grubs is long rooted, healthy grass and an environment with lots of natural predators.  If you can not control grubs with cultural practices alone, nematodes have proven effective when properly applied.  Raking the area, top dressing and re-seeding can repair grub damage.

Chinch Bugs are small insects that grow to about 4mm. in length. When they first hatch they are red but darken as they mature. Chinch bugs have piercing mouth parts and feed on the crown and stem of grass, sucking out the sap from the plant.  Chinch bugs thrive in dry weather. 

Damage to lawns is always more severe in hot, dry summers. The injury appears as irregular sunken patches of dead grass and is usually noticed in August. Chinch bugs like to hide in thatch and prefer sunny dry areas that are poorly watered. 

Core AerationA good horticultural program with thatch reduction, core aeration and proper fertilizing will go a long way to preventing problems with chinch bugs.  Research has also shown that over-seeding with grass that contains endophytes offers some resistance to chinch bug feeding.

Leatherjackets are a relatively new insect problem. The leatherjacket is the larva of the European Crane Fly, a flying insect that looks a lot like a very big mosquito that doesn’t bite. Leatherjacket larvae are grey-brown in colour, legless, tubular in shape and are mostly seen under the soil surface. They primarily feed on the roots and crowns of grass in spring (April and May), but will also come to the surface and feed on stems and grass blades. 

Leatherjackets can seriously damage a lawn when they are present in large numbers and the lawn is already thin or under stress from drought or poor soil.  Birds looking for leatherjackets to eat may also damage a lawn. 

A thick, healthy natural lawn should be able to withstand a moderate population of leatherjackets. If additional control is required, nematodes have been proven effective. We  can provide you with a professional consult to assess your lawn problems. Nematode applications in June, July/August and September as a preventative measure is quite effective.