Underhill's Lawn Care Tips

It is not too often that we witness the onset of a completely new turf pest, but that is where we find ourselves today. The European Crane Fly was a pest previously known to inhabit maritime regions in North America, being first reported on Cape Breton Island in 1955, and in Vancouver in 1965. Then in 1996, indications of damage caused by the larva of this insect, better known as Leatherjackets, were reported for the first time in Ontario. Now it appears as though they are becoming widespread across many areas of the province.

During the fall of 2002, we were called upon to diagnose what turned out to be severe infestations of adult Crane Flies in our customers yards across the greater Toronto area. Richmond Hill, Markham, Scarborough, Uxbridge, Whitby, Oshawa and Brampton seem to have been the regions with the heaviest Crane Fly populations, and the resulting Leatherjacket larvae. At that point, we took the unusual step of immediately informing all of our customers about the potential of this new pest, and to educate them on monitoring for the Crane Flies so their lawns could be protected from future damage.

If we think back to the 80's, we can recall the initial onset of a relatively unknown and troublesome disease called Necrotic Ring Spot, and the subsequent damage it caused as infestation grew. Furthermore, many of our customers can recall how quickly White Grubs invaded Toronto and surrounding area and how devastating this turf pest turned u to be. We weren't going to let our customers be caught uninformed as Leatherjackets began making their headway into their yards.

European Crane Fly adults resemble a large, daddy-long-leg type of mosquito, but they do not sting, nor do they cause any damage to our lawns. They are relatively weak flyers, tending to "bounce" from area to area as they fly. These adult Crane Flies emerge from the soil during late August and September to mate and lay eggs. Then the Leatherjacket larvae begin to hatch within a few weeks, and are a light gray or greenish brown color with irregular black specs and a pointy head. They get their name because of their thick skin. These Leatherjacket larvae will immediately begin to feed on the turf roots, much like a white grub would. Feeding on the grass roots will continue through the fall, and into the following spring as the larvae grow. Significant turf damage can result if left unchecked. During the months of June and July, the Leatherjacket larvae begin to pupate, only to emerge as the adult Crane Flies and start the cycle over again.

Although the life cycle for Leatherjackets is similar to that of White Grubs, control measures are unique for each. First of all, the control products are different, and unfortunately, our Merit white grub control is not effective on leatherjackets. Secondly, the timing for control treatments must be altered for leatherjackets. Here is the schedule to rid your lawn of leatherjackets before they can cause damage:

Watch for the adult European Crane Flies during September. This is a tell tale sign that your lawn will be used for a leatherjacket feeding ground, with damage to the grass rots commencing within weeks.
Call to book our Fall Leatherjacket Control treatment for October. This will stop any leatherjacket damage for this fall and next spring.
If a fall treatment was missed last year, then an application in the spring will control leatherjackets during their most damaging phase.