CajunGrl, thanks for your response. I don't think it's sumac. I can see a guy getting a sumac rash on his chest, torso and back, but as a girl, I never have my shirt and bra off (the straight line rash extended up onto my chest) so it's just not possible I came into contact with something like sumac in this area of my body.
I did some research for straight line Lyme disease rash this morning. I found this in a thread on another site about Lyme Disease:
"Interesting to note, in the largest Lyme study to date, which was the Lyme vaccine trials (Glaxo SmithKline), it was found that a diffuse blotchy appearing rash was the most common EM, not the "bullseye". Only 60% of patients developed any rash at all.
An EM can take on numerous appearances and shapes. It can be raised or not, it can be hot and/or itchy or it may not be, it may be circular or it may appear as a line or it may be some other shape altogether. Multiple EM's can occur if the bacteria migrate to other sites. Also good to be aware that on darker skintones the EM can be mistaken for a bruise.
There is an excellent picture of this type of long, thin, "straight line" EM in Karen Vanderhoof-Forschner's book."