How to Help Flooded or Waterlogged Trees Recover

Whether it’s due to the after-effects of one of the summer storms or floods that we’ve experienced in Northern Virginia, or simply from overwatering, trees can suffer from too much water. Essentially, waterlogged or flooded trees can drown.

Some trees, like sycamore, pawpaw trees, bald cypress and swamp magnolia (Magnolia virginiana) not only survive but thrive in swampy, wet locations. If you have those kinds of trees on your property, they should be just fine.

But if you have trees that grow better in normal soil conditions, you should keep an eye on any trees that have been inundated with water for signs of distress. Learn to recognize the symptoms of flood damage in trees, how to help them recover, and how to prevent future water damage.

What should I look for?

Even if a tree hasn’t been flooded, it can still be waterlogged (or overly watered). Symptoms of excessive water can include:

• Leaves turning yellow or brown at the edges
• Wilting or drooping leaves
• Leaves browning at the center
• Green leaves that are brittle

It can sometimes be difficult to know if the symptoms above are due to too much water or not enough water – many symptoms are similar. If there’s been recent flooding, it’s pretty obvious why your trees are looking the way they are. But if floods aren’t an issue, check your irrigation system for leaks and make sure the settings are correct (sometimes a dead battery in the controller or a power surge can reset the system).

How can a tree drown?

So how can a tree drown? Doesn’t it need water to grow?

It does, but too much of anything can be a bad thing. Roots not only get water and nutrients from the soil around them, they also get oxygen. Well-aerated soil has pockets of air (oxygen), which the roots take up and send to the rest of the tree.

When the soil becomes waterlogged, the pockets of air are filled with water. Without oxygen, the roots can die. And without roots to sustain the tree and take in moisture, the tree becomes dried out and sickly.

So, in an ironic twist, your tree could die from lack of moisture … because of too much water in the soil. The tree, in effect, suffocates from lack of oxygen and/or dies from root rot.

How can you tell if a tree has too much water?

Watch to see if your tree exhibits any of the signs mentioned above. Leaf scorching or browning will generally start at the top of the tree and the ends of branches. It’s often more noticeable on the side of the tree that faces the wind.

Another sign that there is too much moisture in your soil can be the appearance of mushrooms, algae, or moss around the bottom of the tree. These organisms thrive on excess water.

What can I do?

Prevention is the best cure. If there are areas of your property where you often have standing water, only plant flood-tolerant trees and plants in that area. Any flood-intolerant species should be planted on higher, well-drained ground.

How can I help my trees after flooding?

After a flood, you can’t do anything until the floodwater recedes. And if the water flooding your trees is due to a storm, don’t go out during the storm to “save” your trees. Wait until the weather clears before going outside.

As the water clears, remove debris and excess soil around plants and trees. Look for areas that are not draining well and see if you can improve drainage or divert water away from the trees. If there is mulch around any of your trees, temporarily remove it. Mulch is meant to hold in moisture, so removing it might help the trees “breathe” better.

What should I do if I’ve over-watered my trees?

If the water-saturated ground is due to your own watering, it’s time to change the settings on your irrigation system! And if you water by hand or by setting out a lawn sprinkler, water less frequently and/or supply less water at a time.

The best method for irrigating trees (and many other plants) is to water deeply and infrequently. So if you’re watering every day, it might be too much for your trees to handle.

When is it time to call in a professional?

If you’re not sure how your trees are faring after a storm or if you notice signs of distress in your trees, call a qualified and experienced tree care professional for a consultation. It’s not always easy to tell what’s really affecting your trees. For example, yellowing leaves from root die-back (common after flooding) look very similar to the effects of certain tree pest infestations or diseases. A tree care expert will be able to determine the cause and create a treatment program to work towards making your trees healthy again.

For a longer-term solution for waterlogged trees, sometimes deep-root fertilization can help to aerate the soil around a tree and add back needed nutrients. Professional fertilizer will have a low salt index and slow-release nitrogen to ensure no additional damage to the roots is done.

With more extensive damage, other treatment options may be possible. Contact us to schedule a consultation.

If the area where your tree is located has consistent water pooling, it may be necessary to move the tree to another location where drainage is better and the roots can receive oxygen from the soil. However, this should be one of the last resorts, as moving a well-established tree can harm it further.

Long-Term Care of Waterlogged Trees

It may take waterlogged or flooded trees a few seasons to recover, depending on how long they were deprived of oxygen. Keep an eye on your trees and look for any continuing signs of distress. Many symptoms may not pop up until months later, especially if we have a prolonged hot, dry period.

Stressed trees need extra care, so proper tree care is vital. Working with a tree care professional to ensure that your trees get regular maintenance, such as pruning, mulching, and aeration, as well as watering deeply during dry seasons, can all help to revive your trees.

Finally, if you lost trees due to flooding and want to plant new ones, give us a call. We’re happy to recommend the right trees and where to plant them on your property.