GDD update 7.8.19

Gorgeous day today – although sweat was dripping down my nose while I was digging plants this morning.  And collecting lily leaf beetle larvae. I live a charmed existence (really I do as I like all those things).


We are in that season where most of the eggs are laid, or larvae burrowing, or adults hiding from the heat.  The last few 1st generation pests are just about done and the 2nd generation hasn’t started for many yet.  Most insects – in NYS – only have one generation per year – thank heavens.  If you control them in the right window, you are done for the year. That can change as climates change unfortunately.


We have started looking at the insects we are catching in the habitat plots near our Christmas tree planting to see if we find pest, beneficials, or some that just wandered by.  We have 3 methods for catching insects – pan traps for flying insects, pitfall traps for soil insects, and sweep netting for those on the foliage.  Getting them all id’ed will be a chore but we are trying to have enough information to make some sense for our field day in September.   Lots of hover flies – a predator of aphids – in some plots.  Will that result in reduced balsam twig aphid?  We hope so.


Jason Dombroskie, who runs Cornell’s insect diagnostic lab, was helping (wow, is he good!).  I learned that white pine weevil is one of the adult insects that survives the longest.  John Freckleton can support that as he has white pine weevil traps and always tells me how many he has caught.


Things to look out for:


Japanese beetle adults will feed on leaders of fir and maybe other species.  1029-2154 GDD

They also lay eggs that become grubs that can feed on roots.  Japanese beetle traps are good at catching adults but the worry is that they pull them in but don’t catch them all.  If you use them, be careful where you put them.


Two spotted spider mites will start up again – 1300-2000 GDD

They like the heat.  And dust makes them happy.  Pesticides that kill off beneficial mites will sometimes result in a flush of the species we don’t want.  Also excess nitrogen makes them happy.


Pine needle scale 2nd generation is about to start – 1290-1917 GDD


The last few of the ones you’ve been watching:


Cryptomeria scale crawlers – 600-800 GDD

Elongate hemlock scale crawlers – 360-700 GDD

Bagworm – 650-750 GDD


Have a great week – and see you at Franke’s if you are going to the summer CTFANY meeting.