Hemlocks and heat islands

[KentuckySawyer]

I've been asked to submit a report to a local park, regarding suggestions for improvement of their tree plantings. Most of the tree stock there was installed about ten years ago. Some problems include girdling roots, trees planted much too deep, physical abuse caused by park goers, etc.

There are two stands of Tsuga canadensis in the park. One is doing great and the other is looking pretty ratty. The bad stand is right by a blacktop parking lot while the other is surrounded by other plants and trees. Each stand is located on a small hillside with a slight north east orientation. My thought is that the Hemlocks by the asphalt are suffering from the heat.

Any suggestions on helping these lovers of cool, moist environs? I was thinking of physical barriers, but doubt that the park managers would like this. Seems like transplanting the Hemlocks and replacing with heat tolerant species would be the best in the long run.

 

[smokechase II]

Assuming by their absence in your post that there are no indications of fungus or insects in the damaged stand.

Soils, soil moisture, perhaps excessive sunlight or temps have probably been excluded too.

Try to quantify the air and soil temps in the two areas. That's my best guess.

 

[Sheshovel]

I would say you are correct in your evaluation.Asphault attracts holds and radiates heat
changing the micro climate around trees to a very large degree..Cooling the air with sprinklers in the summer heat in the immediate vicinity of the trees helps alot.Also the trees could be suffering from soil compaction,leaving them unable to get the water they require winter or summer.Run-off instead of absorbtion.a light airy mulch would help both problems.