GDD update 9.27.19

Trying to get back on schedule – whatever that means!


We had some potentially exciting weather last night at the Beneficial Habitat Twilight meeting last night but most of it missed us!  It was nice to see some of you there!


We got a different viewpoint on some possible benefits of even those insects we consider pests from Jason Dombroskie, Cornell’s Insect Diagnostician – who has met few insects he didn’t like in some way.  That benefit might just be that they are food for insects that help control other insects.  We are learning a lot about what types of beneficial insects are in our habitat plots that might help control pests as we evaluate our samples.  Lots of ground beetles and hover flies.


And some good news on spotted lanternfly.  Some areas may not have sufficient GDD to allow completion of the life cycle.  Penn State is studying it now.  Hurray for GDD!


One of the things Maria van Dyke talked about last night is the Pesticide Decision-Making Guide to Protect Pollinators in Landscape, Ornamental and Turf Management.  It is available at the NYS IPM website at,%20Ornamental%20and%20Turf%20Management_022619.pdf


And Amara Dunn did a great job of walking everyone through the plots.   You can live somewhat vicariously by checking out her blog Biocontrol Bytes.

(you can read all the posts if you take off the ?s=habitat at the end of the url)

And what should you be scouting?

Spruce spider mite – 2375- 2806 GDD

Doug fir needle midge – remove heavily infested trees (carefully so you don’t spread the pest) before larvae exit the needles (needles will turn brown). Mark infested trees for placing traps in the spring

Elongate hemlock scale – keep scouting for crawlers.

Cryptomeria scale crawlers – 1750-2130 GDD

Japanese beetle adults – 1029-2154 GDD



Wading River and Riverhead LIHREC have more GDD than anything on the list – but I think you might still do some scouting, just in case the insects don’t read the books.

Have a great week!