How to water trees in a Missouri drought

How much

The Missouri Department of Conservation's drought advice is to give trees the equivalent of about 2 inches of rain a week, soaked in slowly.

To check, set a few cans or cups under the tree while you water and stop when they average 2 inches, or push a screwdriver or probe into the soil and stop when it is wet 6 to 8 inches down.

Where

Water the ground under the canopy, from near the trunk out to the drip line, where the longest branches end. That is where most of the roots that take up water are.

For a large tree, water one section at a time and move the hose or soaker to a new part of the root zone every few days.

When and how

• Water overnight or early in the morning, not in the afternoon heat.
• Use a soaker hose, a slow sprinkler or drip line. For a small tree, a bucket with a few small holes works.
• Don't spray the leaves, and don't push a pipe into the soil to water deep.
• If the ground cracks, fill the cracks with mulch or soil instead of stamping them shut; that can tear surface roots.

Which trees first

Trees planted in the last two or three years lost part of their roots when they were dug and are the most likely to die in a drought. Water them first, then large trees near the house that would be costly to lose.