Either dry roots or wind damage.
Over watering could definitley turn the tree brown. Back off a bit and the tree should recover.
You want to prune an arborvitae by pruning and cutting off all dead branches, dieased branches and also crossing branches. Watch out not to make the finsh cut too close because the shrub will not heal correctly and may cause an infection. You also have to watch not to make your cut too far away because it will take too long to heal and the cut will have more room for pathogens to start where the infection could possible kill the shrub.
The scientific name for arborvitae shrub is Thuja occidentalis.
arborvitae
The American arborvitae tree has simple, scale-like imbricate leaves in four rows.
appleashapricotavocadoAmerican arborvitae
arborvitae
Any tree can be grown in a container. Arborvitae or Thuja occidentalis is no different but it is like all the rest it needs morer care in a pot.
See the related link on what causes brown discharge after period.
I have no idea ! Someone might help out.
Knots are from the branches in the wood when it was a tree.
they camouflage with their environment to be safe from predators. they often blend their colors with branches because of its color brown.