How Long Can a Dead Tree Remain Standing?

Trees often die slowly, but they eventually reach the point where gravity takes over and they fall. But how long can a dead tree remain standing? Some dead trees can stay standing for many years, although it can be difficult to predict. Factors like the wind and the species of tree play a role. Here’s a closer look at what can cause a decaying tree to fall, plus when you should consider removing a tree.

What Causes a Dead Tree to Fall?

In natural forests, a dead tree that stays standing is called a “snag” and is considered important for environmental health. But in your yard, a standing dead tree is a whole different matter—one that carries significant risks if it falls.

In a forest, mature trees that die often stay standing for between 2 and 5 years before they fall. But dead trees are unpredictable, and it’s difficult to pinpoint exactly when one will fall. Decay progresses at different rates for different trees. It could be a matter of days or weeks, or many years before a tree falls. But in nearly every case, trees finally fall because their anchoring root system and heartwood can no longer support them.

Those massive roots do more than just bring in nutrients through the soil: They also help keep the tree, which can weigh up to 500 pounds or more, supported and steady. Once the roots die off and the heartwood starts decaying, it’s only a matter of time before the tree falls.

The diameter of the tree will also dictate when it will fall. Trunks larger than 16 inches at about shoulder height have considerably more heartwood and larger roots which need to decay before the tree will fall.

The other primary factor that affects how long a dead tree remains standing is the wind. Many dead trees fall during seasonal storms, and the added weight from rain or snow only hastens the process. Trees growing in a thick forest tend to have more protection against the elements than isolated trees in your backyard, which is why they often take longer to fall.

The Type of Tree Is a Factor

The species of the tree affects how quickly it will fall. For example, the tough yellow cedars of Alaska can stay standing for decades after they’ve died. Hardwood species often remain standing longer because they resist decay. Species like cedars have antimicrobial properties, too.

The species also affects the shape of the tree, how it distributes weight, and what climate (bad weather included) it prefers to grow in, which could be why research has found that ponderosa pines fall faster than species like Douglas fir or lodgepole pine.

As we mentioned earlier, trees in your yard generally have less protection and tend to fall sooner.

The Cause of Death Also Plays a Role

If a tree dies because its roots were crushed or attacked by disease, it’s more likely that the tree will fall quickly. Trees that are overtaken by root fungus, for example, can die and fall in a matter of months. 

On the other hand, if a tree dies with its roots intact and well-preserved, it’s much more likely to stay standing longer. Trees that died from drought, for example, tend to stay upright until decay has time to slowly set in.

The Dangers of a Dead Tree That’s Still Standing

Unlike forest snags, a dead tree on your property is far from harmless. Once trees reach above 20 feet, they are heavy and tall enough to cause lots of damage when they fall. Your fence, roof, exterior walls, and carefully crafted landscape could all be at risk from a falling tree. Plus, you never know when heavy branches might fall.

If the tree died from disease, it’s possible the disease will spread to healthy trees. The decaying wood also attracts termites and other pests you don’t want near your home. And as the wood dries out, it can catch fire more easily.

Not sure about the status of your tree? It can be difficult to tell when a tree is dying. When in doubt, contact an arborist or similar tree maintenance professional near you for a consultation. They’ll be able to assess the health of your tree, suggest a course of action if the tree can be saved, or let you know it’s time to remove the tree before it falls.

Removing a Dead Tree

If you have experience using a properly-sized chainsaw, cutting down a small tree can be a DIY job. But it’s not safe for homeowners to remove large trees on their own; in those cases, you should contact a professional tree removal service near you to do the job. Tree removal costs range from $200 to $2,000 depending on the number of trees and their size.