1mm-long insect ID from Tennessee
The insects you have found must be of a species of thrips. This excerpt from Wikipedia fits your description well:


  Thrips (order Thysanoptera) are minute (1 mm long or less), slender insects with fringed wings and unique asymmetrical mouthparts. Different thrips species feed, mostly on plants although a few are predators, by puncturing and sucking up the contents. Approximately 6,000 species have been described. 


I won't try to identify the exact species, but here is a photo of a yellowish-orange thrip I have found:

 

Image source:

https://6legs2many.files.wordpress.com/2012/04/thysanoptera_thrips_fringe_wings.jpg