PaBIA September 23, 2015 Eblast

Mature Introduced Pine Sawfly Larvae — credit Steven Katovich, USDA Forest Service

As of September 22:

PaBIA thanks all those who took the time to report on the status of introduced pine sawfly infestation on their properties. We are surprised at the widespread nature of this outbreak and will use the replies to create a map that will identify the perimeter of the outbreak in our area as well as “hot spots.”  So far there have been roughly 90 replies, many reporting severe infestation, some with defoliation. Some remarked in the

PaB Defoliated Tree – Fall 2015

increased incidence of the pine shoot beetle, which also attacks

 trees stressed by drought. So far, the larvae seem to avoid the red pines, which nonetheless are susceptible to a variety of pine shoot and pine cone beetles. Shelagh Grant has been unable to reply individually but wishes to thank everyone who responded.  Their assistance will be invaluable when planning a tour of the area next Monday or Tuesday (depending on weather.) 

On the advice of our local councillors, the Township of the Archipelago (TOA) has kindly arranged for David Bywater (GBBR) and Ken Webb of Westwind to conduct an inspection tour and prepare a report for Council’s consideration.  Shelagh will be accompanying them.  We will be looking for defoliation and any signs of ongoing infestation, primarily from the water but may land at a couple of reported “hot spots.” Should anyone not wish us to visit your site, please let us 

 

As the member of the Environment Committee responsible for Forest Health, Shelagh has been in touch with numerous officials with the Ministry of Natural Resources and Forests (MNRF), the Ministry of the Environment and Climate Change (MOECC), Westwind, the TOA and others. Sandy Boeckh, as director of the environment portfolio has contacted others, including the Georgian Bay Association. The objective is to collect as much information as possible on methods of control and prevention to protect our white pines from further degradation. Our underlying goal is to achieve effective coordination and cooperation among all parties and agencies directly or indirectly involved, towards devising the best strategy possible to be instituted by next Spring. It goes without saying that any proposed action will be designed to ensure overall protection of the environment and health of those residing there.

The most promising news is that heavy rain and wind last week, accompanied by colder temperatures at night, seemed to bring down a sizable number of the larvae which were hopefully too weak to

Introduced Pine Sawfly Cocoon — G. Csoka, Hungary Forest Research Institute

pupate.

If visiting your cottage this fall, you might try to gather and destroy any brown pupae cases found on the ground or lower branches, as these will winter over and produce the adult sawfly which will fly to healthy pine branches in the Spring and lay up to 70 eggs in slits along the

Sawfly Eggs in Needles

needles

‘ edges to produce a new generation of larvae.  At present, the larvae in the pines, especially the tall ones tend to be far too widely scattered in the trees for any form of spraying to be effective. Everyone should keep an eye out for a tight-knit gathering of tiny worms that have just emerged from their egg sacs on small trees or lower branches indicating a third generation.  Depending on the location and size of such a branch, these might be best dealt with by removing the branch and destroying the larvae in your fireplace or pit. Keep in mind that one larvae = one pupa case = one sawfly = 70 eggs and potential of 70 new larvae.  Hence, any closed pupa cases, whether on the ground or a low tree branch should also be destroyed as they can winter over in extremely cold weather. If your trees need water, this should be done by soaking the area slowly with a regular hose to avoid any major runoff that might take precious topsoil with it.

Further reports, especially with photographs showing the extent of defoliation among your pines, are welcome and should be sent to Shelagh to be added to the list.  For those with small islands and only a few white pines, we share your heartfelt concerns and ask for your patience and continued cooperation.   In the interim, we are all hoping that Mother Nature will assist us with ample rain and much colder weather.