I have planted (for the third time) some leyland cypress. Every time before, the plants have slowly turned brown and died. It finally dawned on me that there may be too much salt in the soil. The new trees are beginning to exhibit the same, early browing problems. Is there something that I can pour around the trees on a regular basis (digging the dirt out is not possible) that would counter the salt problem?

You can try balancing out the NaCl salt by applying Epsom Salt (magnesium sulfate), dry molasses, and more mature compost, and maybe even aerobic compost tea, around the salty areas.

This will not not only balance the sodium, chlorine, magnesium, sulfur, potassium, and calcium in the soil, but also bring more soil biology on the scene to help make the soil healthy again.

Thank you. Please further explain 'more mature compost' and 'aerobic compost tea'.

Mature homemade compost is usually at least 1-2 months old, full decomposed, no stinky smells, crumbly, and not hot or warm any more.

Aerobic compost tea is usually made from mature compost in non-chlorinated water (or rainwater), and a little molasses or dry molasses to stimulate and grow the beneficial composting bacteria and fungi and algae in the mixture, brewed in a container over a short period of time (less than 1-3 days), with a bubbling air pump.

Balancing the salt is the answer but you have to know what salts and how much before you can deal with it. Visit the Texas Plant and Soil Lab website and look for the test that covers salts. Get that and tell them what you are trying to do. Also tell them you are organic and they will give you a long list of things you can do.