Is this needlecast on my Tsuga mertensiana?

[G-Hoppa]

Any hemlock people out there seen this before? Could it be Rhizosphaera needle cast? If so, I'm thinking Mancozeb. But it doesn't seem quite right - I can't see the tell-tale little black spores, and it's not just the inner needles - it's all along the branch on several branches.

 

[NOZZLE HEAD]

It’s possibly the Rhizosphaera needlecast. You may not see the little black spores if the tree itself is fighting the fungus.

All mancozeb will do is stop it from spreading to new growth. Which may be uninfected if the black sprores aren’t out yet.

A systemic fungicide will be more effective at protecting the new growth as it elongates. A product containing “phosphites” should help as well.

 

[G-Hoppa]

Well, in between rainy spells, I've used Mancozeb to hopefully stop infection of the new needles. I just received my order of Bonide Infuse (similar to Cleary's from what I understand) - so now it's time to figure out dosage of the systemic.

 

[River's Edge]

Well, in between rainy spells, I've used Mancozeb to hopefully stop infection of the new needles. I just received my order of Bonide Infuse (similar to Cleary's from what I understand) - so now it's time to figure out dosage of the systemic.

I have used 1 teaspoon per container of two gallons. It has been effective with no adverse affects that I have noted. Sprinkle on the surface and water as usual. Noted improvement in tree health within three to four weeks in my experience.
I have never seen needle cast on a Mountain Hemlock, so cannot help you with that part! Was the tree recently collected within the last year?

 

[G-Hoppa]

I have used 1 teaspoon per container of two gallons. It has been effective with no adverse affects that I have noted. Sprinkle on the surface and water as usual. Noted improvement in tree health within three to four weeks in my experience.
I have never seen needle cast on a Mountain Hemlock, so cannot help you with that part! Was the tree recently collected within the last year?

Thanks for the tip on dosage.
This Mtn Hemlock was collected maybe 3 years ago, and it's been in my yard for 2 years. I haven't seen that type of needle discoloration before. I have a half dozen collected Mtn. Hemlocks in various stages of development, and none are showing that symptom. Hasn't seemed to slow down the spring flush on this tree, whatever it is.

 

[River's Edge]

Thanks for the tip on dosage.
This Mtn Hemlock was collected maybe 3 years ago, and it's been in my yard for 2 years. I haven't seen that type of needle discoloration before. I have a half dozen collected Mtn. Hemlocks in various stages of development, and none are showing that symptom. Hasn't seemed to slow down the spring flush on this tree, whatever it is.

Watch the new needles for a pattern of banding developing! The completely brown needles look like physical damage. A few show the light tan interspersed with green portions that are indicative of a fungal issue.