Arborvitae Have Suddenly Turned Brown On Outside

Question From: M. McCarty - PENNSYLVANIA
Q: We have ten arborvitaes in our back yard and four at separate locations have very quickly (within two weeks) turned brown however there is still some green on the inside. The other six are shedding mildly and are quite tall whereas the four browned ones are only 6-7 ft tall. None of the ten in the back yard have ever shed however the ones in our front yard shed about every two years then they'll go into a growth spurt. Could it be the four in the back yard had gotten too thick over the years and just needed a good shedding in order to grow taller?

A: Sudden browning is often caused by chemical damage often the result of drift. And it doesn't necessarily have to be a pesticide. Power washing with chemicals toxic to plants will do it. I suggest you get an onsite inspection from a certified arborist. To find one in your area go to and enter your zip code. Best Nancy and Happy Gardening.