March 22, 2016

Christmas Tree IPM Update 3.22.16

Just a little snow fell at my house yesterday but it still feels springy!

And that leads us directly into the first question I received this spring:  When should I treat for white pine weevil?  Now (although maybe a slightly warmer day than today) urging by the Cornus maas blooming outside my office window and the silver maple I saw blooming in Geneva last week.  7-58 growing degree days.  You are trying to control the adults before they lay eggs and you know how a young white pine weevil’s fancy turns to love in the early spring.  Target the top third of the plant where they hang out.

Brian’s blog post on wpw:
For more pictures:
Do you get Sarah Pickel’s PA Christmas tree IPM report?  A good way to see what is heading our way.  Contact her at: c-sapickel@pa.gov
Sarah Pickel | IPM Education Specialist
PA Department of Agriculture | Bureau of Plant Industry
2301 North Cameron Street | Harrisburg, PA 17110
P: 717-772-5227

What is she seeing besides white pine weevil?
Pales weevil – larger than White pine weevil and with different habits.  While mostly a pine problem, the adults will feed on the bark of other conifers resulting in flagged or dead branches.  Eggs and larvae are only found in newly cut (less than a year) pine stumps so chipping or removing pine stumps is a good management practice.

Eriophyid mites – just starting.  These mites are tiny so it takes close scouting.  They can be carrot shaped or more elongated.  The eggs may be in clusters on the bottom of the needles.  Just a bit larger than the stomata spots.  There is a threshold for this pest – 80% of twigs with mites and at least 8 mites on a single needle on one shoot.  Get your hand lenses out!
Are you out in the trees yet?  I bet you are on the warm days.  Seems appealing when I am in my office.  I did walk my  conifer plantation the other day, though!  Lost one but the other 8 are happy.  🙂

Have a great week!