Trees have an extraordinary ability to suck water out of the ground, but only if there’s water there. And not all trees are the same. For example, oaks are deep rooted and can pull the smallest particle off a particle of soil. Maples have a little more difficulty.

Trees suffered during summer’s heat and drought.

Recent rains provide a guideline on what’s alive and what’s dead in turfgrass. For trees, it may be a couple of years before the full extent is known.

Trees have an extraordinary ability to suck water out of the ground, but only if there’s water there. And not all trees are the same. For example, oaks are deep rooted and can pull the smallest particle off a particle of soil. Maples have a little more difficulty, and you can find browned leaf edges, though on some silver maples it may appear almost black.

You’d think that evergreens would be a little better off. They have resin to help them reduce water loss. But this year you’d be wrong. Many evergreens suffered but none worse than arborvitae.

Arborvitae look like someone smashed their branches in a press, creating a flattened branch. Plants are often used as living fences to screen out unwanted views, which might include some neighbors.

Sadly the plants aren’t efficient at conserving moisture or drawing it out of the ground. Individual branches start off with an olive green color followed by a greenish-beige followed by brown. Then the whole plant goes.

Once a plant dies, it’s gone. It won’t come back no matter how much you water, fertilize, swear, beg or pray. If it comes back, it wasn’t dead.

What to look for

So, how do you know for sure? There are a few clues.

If the leaves all are brown and the branches snap like a piece of uncooked spaghetti, get the chainsaw. If you see bark splitting and mushrooms growing out of the base of the tree on top of the brown leaves, give it last rites.

If the leaves are brown but the branches bend like cooked spaghetti, the tree might still be dead. But it could be alive. You’ll need to whittle some of the bark to see if you can see white or green beneath. If the inner pith or wood is white or green, wait until spring. This is a good sign.

Some trees turn brown or drop lots of leaves to save itself. This self-preservation can give the appearance of a dying plant and that’s where problems arise with unsuspecting tree lovers.

If you see nothing but brown under the bark, the tree is probably dead. Because it’s not 100 percent certain the tree is alive or dead, wait until spring to be sure. If it doesn’t leaf out in the spring, it’s dead.

Evergreens tend to drop lots of old needles as their defense mechanism. As long as the new needles are still green or blue, don’t worry until next spring. Just remember that larches and bald cypresses shed all their needles in the fall.

If the current year’s needles turn brown and fall off, check the terminal buds. These buds at the end of the branches will be covered with brown scales, but should be green underneath.

If they are green, wait until May to see if new growth is expanding. Live buds also tend to hold to the limb and take some pressure to pop off.

Buds that are brown and/or pop off easily are not a good sign. Without buds, the tree won’t produce new growth.

Taking action

The best thing you can do is a two-pronged attack.

First, water. Water deeply where the roots are. Water slowly so it soaks down to the roots, past the turfgrass roots. The goal is to wet the soil 12 to 18 inches deep. Watering slowly will allow water to percolate down and then horizontally across the soil profile.

This isn’t a one shot operation. It’s something you do this weekend, and then every other weekend until the ground freezes. The only reason to stop is if it rains 10 to 12 inches over the next eight weeks. Rake the leaves on the alternate weekends or water after raking.

If we get 2 inches of rain during one of the weeks, you can omit the watering that week if you want. But if you do water, it won’t be wasted as long as the water saturates slowly.

Of course follow the water regulations or restrictions of your community.
The other thing to do is to fertilize the plants.

Fertilizing will help stimulate root growth over the next seven months. Coupled with soil moisture, this year’s drought and heat effects can almost be reversed by next April.

Fertilizer won’t bring back a dead or dying tree. Too much fertilizer can hasten death by burning roots that are needed to provide water.

It’s important to get the fertilizer to the tree’s roots and not the lawn’s if there is grass under the tree. You’ll either need to use a deep root feeder or create a grid of holes 12 inches deep every three feet in a ring at the dripline of the tree, another ring three feet out and a third ring three feet in.

Just put 6 ounces of regular garden fertilizer in each hole. And water.

David Robson is a specialist with University of Illinois Extension.