Sick Scots Pine trees.

(Question)

Hello,
I have two mature Scot’s Pine trees in my yard that are having trouble. Dying lower branches, brown needles and thinning. They are about 25 years old. I also have a groundhog that burrows nearby. Do you think that is my problem? What should I do?

(Answer)

Hello,

Thank you for contacting Toronto Master Gardeners.
Unfortunately your photos are not very clear and just give a general overall view of decline  in the needle growth. It is almost impossible to diagnose from the information and photos provided.
A number of issues can affect Scots pines including:
Fungal disease.
Insects
Root issues
Drought
Trees planted too deep
Girdling roots
I would suggest that you contact Landscape Ontario to find a certified arborist near you to inspect the trees.  Certified arborists are qualified to treat disease and insect problems.
Some of the diseases affecting Scots pines and appearing at this time of year are outlined below:
Pine Tree Disease Overview

Disease: Dothistroma needle blight
Symptoms appear:March/April
Species: Primarily Austrian but also on Red pine, Scots pine
Timing of control: May – July

Disease: Lophodermium needle cast
Symptoms appear: April/May
Species: Primarily Scots pine but also found on Austrian and Red pine
Timing of control: August – September

Disease: Brown spot needle blight
Symptoms appear: August/September
Species: Primarily Scots pine but also on Red pine, Austrian
Timing of control: May – June

This article was published by Michigan State University Extension

I hope this was helpful.

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