Spruce are not the only trees in trouble. Apparently problems with trees in Calgary relate back to the “Snowtember” event of 2014, the hail last summer and the drought this spring.

Anita Schill is a Registered Consulting Arborist (the highest level of Arborist) and a good friend. My daughter Chelsie Anderson is a private gardener (http://chelsies.ca/) and she posed the question because she keeps seeing her client’s birch trees turning brown. Schill says (by email) that this dieback is entirely expected:

[There are] Several possible reasons… first- the September snow storm in 2014… secondly-several severe hail storms in 2015.. third- a VERY dry spring in 2016.

This is the first year that my birch has looked bad and [it has] birch leafminer – haven’t seen that on my tree for years which tells me how stressed it is. Several branches are dead – mainly on the NW side- which took the brunt from a major hailstorm- we were lucky in Airdrie as far as the snowstorm… not too much branch damage but Calgary was devastated.

I’ve been watering my tree when it’s dry but don’t expect it to recuperate for a few years.

[Tree stress] Depends on the health (stored energy reserves) of the tree. In the case of my tree, it is about 25cm in diameter and has been grown in my yard from a seedling so it is very established and I assumed has lots of reserve energy. Compare this to a recently transplanted tree that has to use reserve energy trying to re-establish it’s root system let alone deal with storm damage.

My tree had multiple wounds along pretty much every branch on the NW side so it had to use reserve energy to seal those wounds. I’m assuming energy reserves were low after that because it was very susceptible to birch leaf miner. The whole tree looks brown but I now have 15-30 cm of new “green” growth at the branch tips that is unaffected. Even though I’ve been watering, nothing is better than these amazing frequent rains we are getting. I believe my tree will be able to reestablish its energy reserves over time [years].

As I said though, I had watered this tree during the dry spring we had. I can see that this helped because the new flush of growth is evident. I’ll continue to water should we get another dry spell… well into fall. I predict that the growth flushes will continue to occur.

On the other hand, a tree that was left dry this spring may shut right down for the year. In this case, rain and watering will not initiate another growth flush this year but will hopefully still help for next year. Check the tree to see if it is establishing winter buds in the axils of the leaves which will help you decide if the tree will have a chance. Keep the soil moist but not waterlogged, mulch would be helpful… Next spring will give you better answers. The tree will decide which if any branches and twigs will be growing. You will easily be able to see which are alive and which are dead. Wait until the leaves have fully expanded before pruning out the dieback.

Anita Schill is a registered consulting arborist. She can be reached through her web page at http://www.treeandleaf.ca/