Pine Wilt, etc.? - Ask Extension
The two attached photos are of the same Ponderosa Pine on our land in Woodmen Valley, on the west side of I-25 and between Colorado Springs and the US...
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Pine Wilt, etc.? #828831
Asked May 07, 2023, 3:47 PM EDT
The two attached photos are of the same Ponderosa Pine on our land in Woodmen Valley, on the west side of I-25 and between Colorado Springs and the US Air Force Academy. The pine needles at the top and at the ends of several branches are brown and those on the rest of three are not as green as other adjacent Ponderosas. There are no obvious pitch tubes on the trunk. I have had several other trees on my land with this appearance, and I have cut them down and disposed of them.
Does this look like Pine Wilt? If so, do I need to bring the tree down and dispose of it?
Thank you for your assistance,
Justin Morrill<personal data hidden>
El Paso County Colorado
Expert Response
Hello Justin,
Thank you for your very interesting question about what is killing your Ponderosa pines. It was thought in the past that Ponderosa pines had a natural resistance to Pine Wilt Disease. Currently, it has been found that stressed Ponderosa pines can be killed by this disease. I see light brown needles all over the tree. I am sending information about Pine Wilt Disease so you can compare the information with what is happening to your tree. If your tree has Pine Wilt it should be removed to help prevent further spread by pine sawyers. You can confirm this possible diagnosis by sending a sample up to the Plant Diagnostic Clinic up in Denver.
https://agsci.colostate.edu/agbio/plantclinic/
https://extension.colostate.edu/topic-areas/yard-garden/pine-wilt-disease-2-915/
I am also sending information about Mountain Pine and ips beetles which can attack stressed Ponderosa Pines.
https://extension.colostate.edu/topic-areas/yard-garden/pine-wilt-disease-2-915/
https://extension.colostate.edu/topic-areas/insects/mountain-pine-beetle-5-528/
I am also sending Environmental Disease of Woody Plants, please take a look at the drought section. The symptoms do not seem to match in the pictures to indicate drought damage.
https://extension.colostate.edu/topic-areas/yard-garden/environmental-disorders-of-woody-plants-2-932/
If you would like an arborist to come look at your tree please see the information below.
https://www.treesaregood.org/
Thank you for your very interesting question about what is killing your Ponderosa pines. It was thought in the past that Ponderosa pines had a natural resistance to Pine Wilt Disease. Currently, it has been found that stressed Ponderosa pines can be killed by this disease. I see light brown needles all over the tree. I am sending information about Pine Wilt Disease so you can compare the information with what is happening to your tree. If your tree has Pine Wilt it should be removed to help prevent further spread by pine sawyers. You can confirm this possible diagnosis by sending a sample up to the Plant Diagnostic Clinic up in Denver.
https://agsci.colostate.edu/agbio/plantclinic/
https://extension.colostate.edu/topic-areas/yard-garden/pine-wilt-disease-2-915/
I am also sending information about Mountain Pine and ips beetles which can attack stressed Ponderosa Pines.
https://extension.colostate.edu/topic-areas/yard-garden/pine-wilt-disease-2-915/
https://extension.colostate.edu/topic-areas/insects/mountain-pine-beetle-5-528/
I am also sending Environmental Disease of Woody Plants, please take a look at the drought section. The symptoms do not seem to match in the pictures to indicate drought damage.
https://extension.colostate.edu/topic-areas/yard-garden/environmental-disorders-of-woody-plants-2-932/
If you would like an arborist to come look at your tree please see the information below.
https://www.treesaregood.org/
Thank you very much, Barbara.
Sincerely,
Justin Morrill
From: ask=<personal data hidden> <ask=<personal data hidden>> on behalf of Extension Foundation <<personal data hidden>>
Sent: Monday, May 8, 2023 10:46 AM
To: justin_morrill <<personal data hidden>>
Subject: Re: Pine Wilt, etc.? (#0098757)
Sent: Monday, May 8, 2023 10:46 AM
To: justin_morrill <<personal data hidden>>
Subject: Re: Pine Wilt, etc.? (#0098757)
You are welcome.
