The scouting report of The Morton Arboretum for April 19, 2019.
What indicator plant is in bloom at the Arboretum?
Corneliancherry dogwood (Cornus mas) is in flower
Accumulated Growing Degree Days (Base 50): 40.5 (as of April 18)
Accumulated Growing Degree Days (Base 30): 592 (as of April 18)
- Hemlock needleminer
- Boxwood leafminer
- Boxwood psyllid
- Volutella blight on pachysandra.
- Black knot
- Ficaria verna, a weed of many names
- A little thought about growing degree days
- Crabgrass preventer update