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Hi I have forwarded pi... #154345

Asked September 25, 2013, 11:42 AM EDT

Hi I have forwarded pictures to Mary Kay Malinoski and attached one here. Have a major problem on west side of four mature white pine. 95% of visible bud growth on west side for this year looks like the picture submitted (Typical). There is a minor problem on the east side (5%). do not know if this is insect or other damage. Only one of several cut open did contain a single larvae. One, pictures sent, had a spent cocoon attached to it. The rest that I have cut open look like the "interior" picture sent to Mary Kay. Impression is that once the 2012 needles drop the west side of the trees will be completely bare. See "Possible 2012 Damage". Assume this will eventually kill the trees? Wes Earp

Howard County Maryland

Expert Response

Thank you for the additional photographs.  They were examined by several members of our professional staff and the consensus among all of them is that there is no visible evidence of insect or disease.  In fact, the damage strongly resembles herbicidal damage.  Your tree appears to be an Austrian pine instead of a White pine, and Austrian pine is very susceptible to a disease known as Diplodia Tip Blight, but some of the more classic symptoms of that disease are absent.  Also, the tips of the branches are more 'distorted' in appearance which is strongly symptomatic of herbicidal damage.
The question might be asked: was some form of broadleaf herbicide applied to the soil in the general vicinity of the tree's root zone?  Such an application could have been made earlier in the year, perhaps in the spring. 
No treatment is necessary.  Simply wait and see how the tree responds in the spring.  You should see new growth sprouting from each branch just below the damaged area.  If you wish, you can then remove the damaged tips. 
LS
Hi,

Thanks for the response.  The trees are White Pine not Austrin.  But, you are most likely correct in in your conclusions.  The damage is limited to one side of the trees and all are in a row along the the property line.  We do no lawn maintenance other than mowing but several of the properties that abut ours do use lawn care companies.  This would be the second case of herbicide damage this year from a neighbor's activities. 

This damage reaches heights of 40 feet or more suggesting a highly volatile compound.  The damage is approximately five feet inside the property line but the companies don't respect it, so an application could have been made right up to the "drip line".  Is this typical of 2,4 D or other broadleaft compounds?  Or, is it more likely a case of bad timing with regard to wind direction, temperature, or microclimatic affect?

Wes Earp
The Question Asker Replied September 27, 2013, 9:36 AM EDT
There are two herbicides that have demonstrated damaging effects on needled evergreens.  Imprelis is no longer available,  but the other, Dicamba,  is still available in many formulations, even those available to homeowners.  This herbicide is included in several combination products.
Both can move through the soil, although topical application sometimes results in surface movement.  2,4-D and glyphosate are more capable of volatilization and airborne drift.
LS

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