Why they die in a row rather than one at a time
Leyland cypress was the default privacy screen in Middle Tennessee subdivisions for two decades. It is fast, cheap and evergreen, and it was normally planted four to six feet apart in a single line down a side or rear lot boundary. That spacing is the problem. At maturity those trees are competing for the same water in the same strip of ground, and stress is what invites Seiridium canker in.
Once canker is in a row it moves. You see one tree flag brown from the inside out, then its neighbour, then a third, usually over two or three seasons rather than all at once. By the time a homeowner calls us, the typical White House job is not one dead cypress. It is four to nine of them along a fence line, half of them completely brown and the rest on the way.
A screen is one root mass, not eight stumps
Planted that tightly, the root plates knit together. Between adjacent trunks you get a continuous mat of woody root two to six inches under the surface, and by the time you have ground the third stump you are no longer cutting discrete stumps at all, you are working a strip.
That changes the machine plan. The wheel spends more of its time in a shallow, wide sweep along the line than it does dropping into a single face, and the total spoil is larger than the stump diameters suggest because so much of the volume is that connecting root mat. It also means the finished result is a trench-shaped disturbance the length of the row, not a set of round patches, and it will need soil and seed rather than just raking. Plan the repair when you plan the removal.
Access is the whole quote
Leylands were planted on the boundary, which is where the fence is. On the tighter White House lots, and Indian Ridge and Holly Tree are the obvious examples, the strip between a fence and the house wall can be under three feet. A tow-behind machine will never see that ground.
What we need to know before quoting is the narrowest point on the route and whether a fence panel can come off. Often the cheapest version of the job involves removing two or three panels, working the row from the open side, and putting them back. That is worth a conversation with the neighbour whose fence it is. Second question: which side of the line are the trees actually on. A screen planted in 2004 by eye is frequently not where the deed says the boundary runs, and that is worth knowing before a machine is switched on.
What to plant instead, if anything
The instinct is to replace like for like and the result is the same call in eighteen years. If the screen is going back, spacing it wider and mixing species is what breaks the pattern, since a canker that takes one plant does not automatically take the next one along.
Eastern red cedar handles this ground and this drainage without complaint. Nellie Stevens holly is already common in the newer White House builds and takes a hard shear. Where a fast screen genuinely matters, an arborvitae like Green Giant is a more durable choice than Leyland in the same slot. Whatever goes back, do not plant it into the grindings. Wood chips are a poor rooting medium and they tie up nitrogen as they break down. Pull the spoil out, backfill with topsoil, then plant.
The short version
A dead Leyland screen is one connected job, not a set of separate stumps, and the connecting root mat is what drives the spoil volume and the price. Sort out fence access and the property line before booking, and if you replant, widen the spacing and change the species.