Spraying Horticulture Oil when trees are dormant.

We use the term "Dormant" oil when describing the Horticulture Oil sprayed in the spring to suffocate aphid eggs and scale.

This is a very important application in that it is organic, and does not harm beneficial insects.

Every spring I get the question, "my tree is in bud - isn't it too late to spray dormant oil".

Twenty years ago...yes, today...no!

We still use that term "dormant" because it is far more practical to layer the bark with the oil when leaves are not in the way; however the new Supreme Oils are safe to spray over buds and leaves.
Article on newer refined oils we use.

The other question is rain, "will the rain ruin the oil application."

The oil is distributed with water as the carrier so a light rain is  not going to have an effect.

I strongly encourage using the organic oils and even warranty the tree if you have done a oil application and a systemic drench because these applications are so much more environmentally sound.

Boise area browned evergreens

Why are my evergreens brown and are they dead?

You may have evergreen trees that look like a blow torch was waved over them. This is from the sudden deep freeze we had around Thanksgiving last year. Normally these trees would be very cold hardy but they need a slower cold process to harden off for winter and last fall they did not get that.
Here is an article from the Extension office in Utah about the situation.

So are they dead and should you replace them?
Trees never do anything fast, so we should never had a fast reaction. Give them time and see if they recover. I am doing deep root feedings (Normally done in the fall) on these damaged trees. An interesting observation is that the trees I have been deep root feeding for two or more years did not show any damage. Healthy trees have a better ability to withstand strange weather changes and environments.

Cost to do a deep root is around $8 a tree with a $44 minimum.