Many people are wondering this spring if their trees are still alive after the winter storm in February. Live oaks are especially stressed and are looking bare, while crape myrtles have been very slow to bud out, and some appear completely dead from the ground up. Palm trees were greatly affected by the freezing temperatures as well, and in Austin a large percentage died.
It’s difficult to know which damaged trees will survive. According to Ben Bertram, head arborist for Treefolks, “If it has green leaves now, it’s not a guarantee that it’s going to live, but if it doesn’t have any green growth right now at this point, it’s definitely something that we need to be concerned about.”
However, arborists continue to find trees they thought were dead starting to grow new buds. The consensus among professionals at Texas A&M Forest and across the state is wait and be patient. Trees such as live oaks may end up remaining partially bare this year but should develop normally next year.
Inspecting Storm-Damaged Trees
Here are some points to check that will help you determine whether a damaged tree is worth keeping:
- Major broken branches. The larger a broken branch, the more difficult it will be for the tree to recover. It has little chance of surviving if the majority of its main branches are missing.
- Missing leader branch (vertical stem at the top of the trunk). A missing leader weakens the structure and destroys the tree’s natural shape. The tree may live but can become either stunted or misshapen.
- At least half the tree’s crown (branches and leaves) should be left undamaged. A tree missing more than 50 percent of its branches likely can’t produce enough leaves to nurture it through the season.
- The remaining branches need to be able to fill out a balanced tree structure. You want a pleasing shape and appearance when the tree replaces its missing leaves.
- Size of wounds from broken branches or damaged bark. The smaller the wound is in relation to the limb size, the more likely it is to heal. For example, a 2-3-inch wound on a 12-inch diameter branch will be covered in new bark in a couple of years. An unhealed wound leaves the tree susceptible to pests and disease.
- The tree fails a scratch test. Use a fingernail or pocketknife to remove a small bark strip. It still has life if the area underneath is green and moist. In a dead or dying tree the area will be brown and dry. Repeat this test over several areas of the tree to determine if just a few branches are dead, or the entire tree.
- The trunk is split, or the tree was already weakened by disease or pests before the storm. In this case, the tree probably isn’t worth saving.
This is a term used for trees that according to the arborist Matt Petty “are dead, and just don’t know it yet. They’re in decline with crippling health or safety issues that are not visible to the untrained eye.”
Zombie trees have always been with us, but this year’s storm created more when the vascular systems in some trees became freeze-dried. These trees can still have green leaves, but the branches will look worn and brittle. Some may be hosting insects, have a few cracks in the trunk, or are covered in fungi. They may even look completely healthy but are actually rotting from the inside out.
Most zombie trees should start showing telltale signs in July and August with the heat, while it may take years before others display death symptoms. Some of these can be saved, but others should be removed before they fall and injure people or property.
Call an Arborist
If you’re not sure the damage is severe enough to warrant removing the tree, or you also want a check for hidden damage, call in a professional ISA Certified arborist. An arborist will also assess and rehabilitate a zombie tree if it’s worth saving.
You can also use the scratch test on a shrub to see if it’s dead by scraping a small area of a branch’s outer bark with your fingernail or knife. Green, moist tissue indicates life. Try several areas of the shrub, especially close to the roots where new growth shows first.
As well, try bending a small branch or twig. Dead branches and twigs break or snap off, while live ones are flexible. A shrub can have several dead branches and still be alive, so test more than one.
For shrubs that appear dead — with no green tissues when scratched and twigs that break when bent — leave them until the summer. If no growth appears by then, remove them. But if there’s strong sprout growth at the bases, you can cut the shrubs back to within a couple of inches of the soil line. The sprouts can then be trained as the new trunks. This can be done with varieties of crape myrtles that aren’t sending out new growth along their upper stems, and they then should regrow quickly.
Dead Tree Removal
Should you decide to remove a tree, hire a professional if the tree is large. A professional has the proper mechanical equipment and guide ropes for removing large branches before the tree is cut down. For smaller trees that you can fell yourself, take the following steps:
1. Wear the proper safety equipment:
- Steel toe boots
- Pants and long-sleeved shirt
- Hard hat
- Safety goggles
- Ear protection — plugs or earmuffs that reduce sound
- Work gloves
2. Make sure there are no overhead obstacles such as trees or wires that would prevent the tree from falling. Next, clear the area around the tree — at least a distance double the tree’s height.
3. Choose the most natural direction for the tree to fall (e.g., tree leans to the right).
4. Plan two different retreat routes, and make sure each has a clear path. Take the first route if the tree falls in the expected direction, and the second route if it doesn’t.
5. Use an axe or chainsaw to make a cut at a 70-degree angle into the side of the tree facing the direction you want it to fall. Make the cut about 1/4 of the tree’s diameter.
6. Turn the chainsaw or axe sideways and cut horizontally to meet the bottom of your first cut. Stop when the two cuts meet to create a notch.
7. On the opposite side of the tree make a horizontal cut directly behind, and slightly above the notch, leaving 1 inch of wood to make a hinge. Don’t saw completely through the trunk.
8. Pull your chainsaw or axe out and take your first retreat route as the tree falls. If the tree doesn’t fall immediately, push on the hinge so the tree falls in the proper direction.
9. Remove the branches (limbing), starting at the bottom of the tree, and working your way to the top. Do this twice, removing branches on the opposite side from you so the tree is providing protection from the chainsaw.
10. If using the log for firewood, cut it into 24-inch lengths. Then cut the branches into lengths for bundling, according to local collection bylaws.
To keep your sprinkler system in peak condition, call the experts at Smart Earth Sprinklers at (512) 694-1147 or contact us online.