I have a need for a hedge for privacy and to block a bad view problem, and for this to work it needs to be evergreen.

However, the site has a very high water table, there has been some tree rot in deciduous trees, and the hedge would be understory, so the light could vary from half day sun to very shady.

What could I use for this? Fast growing would be helpful.

Dear MP,

The most shade tolerant evergreen is a Canadian(Eastern) Hemlock, yet literature suggests the need for moist, yet well drained soil. Arborvitae may also be a choice, again provided with a well drained soil. To achieve this you can plant very shallow, use a planting berm if possible. Start out with smaller rather than larger plants to allow them to aclimate to the wetter soils. Even raising them up six inches can make a major difference.

Because they would be growing in an understory situation, lightly pruning them to help them fill out to provide the privacy you desire. Planting two rows, alternating the them will get you privacy quicker too.

Sincerely, RH