Trees, Shrubs and Conifers: Ailing Leylandii Cypress, 1 by MollyMc

MollyMc wrote:
I have about 19 of these planted with 8-10 feet spacing, intended to make a living fence in this area of the yard.

They all received equal watering, same amount of fertilizing, sunlight etc. One is really brown and 2 more look like they are on their way.

I chose these trees for this area because they are supposed to like the soil conditions here, naturally and because they are drought tolerant.

Any ideas on what ails them?