Lightning Strikes: Case Study of a Spotted Gum in Adamstown Heights

Understanding the Impact of Lightning Strikes on Trees: A Case Study

Approximately six months ago, a dramatic event unfolded when lightning struck this extraordinary Spotted Gum (Corymbia maculata) in Adamstown Heights. After witnessing the unsettling incident, the vigilant customer immediately contacted Waratah Professional Tree Care. Our knowledgeable senior arborist, Steve, swiftly arrived at the scene to conduct a thorough assessment of the damage. He implemented a careful remedial prune aimed at enhancing the tree’s prospects for recovery. The entry and exit wounds from the lightning strike were clearly visible, whilst the neighbouring tree suffered catastrophic damage, losing all of its foliage due to the overwhelming force of the lightning.

Following the incident, the customer observed a significant decline in the health of the tree. Concerned about its condition, they requested Steve to return for a follow-up assessment to evaluate the tree's potential for recovery after the storm.

What Are the Long-Term Effects of Lightning Strikes on Trees?

The charred electrical patterns, known as Lichtenberg figures, were distinctly visible, marking the bark of the trunk. Both the entry wound, where the lightning struck, and the exit wound, where it earthed, were easily identifiable and unmistakable.

Lightning does not merely scorch the outer bark of a tree; the internal damage it inflicts can be considerably more severe and widespread.

When a bolt of lightning strikes a tree, the immense electrical charge travels through the tree, seeking the path of least resistance to the ground, typically through the water-conducting tissue located just beneath the bark. The heat generated is extreme and instantaneous, effectively boiling the sap within the cambium layer, which is the thin band of living cells responsible for the tree's growth and the transport of essential nutrients and water throughout the tree.

Once the cambium layer is compromised, the tree loses its ability to transport sugars from the leaves down to the roots and water from the roots to the leafy canopy. The affected cells perish, growth halts, and overall vitality diminishes. This loss critically undermines the structural integrity of the tree.

The tree does not die instantly, which is why the decline may take weeks or even months to become visually apparent. This particular Spotted Gum shows some signs of regrowth, indicating that it is still struggling to survive. However, the overall prognosis remains uncertain and cautious.

What Are the Prognostic Indicators for This Tree's Recovery?

The extent of damage the tree sustained relies heavily on how much of the cambium layer was destroyed and whether the root system also suffered from the earthing strike.

Steve’s assessment revealed several urgent priorities:

• Immediate safety measures: It is crucial to monitor the structural integrity of the tree. A tree that has been struck by lightning may appear stable while being severely weakened internally. Any substantial deadwood present in the canopy poses a falling hazard and requires prompt attention to prevent accidents.
• Vigilance for secondary infections: The wounds created by a lightning strike can serve as entry points for fungal diseases and wood-boring insects. A compromised tree becomes vulnerable and necessitates close observation and dedicated care.
• Regular evaluations: The amount of regrowth observed in the coming months will provide valuable insights into the tree’s long-term prognosis. If the regrowth is robust and continues, there is hope for recovery. Conversely, if it stalls, removal may ultimately be the safest option to mitigate further risk to nearby structures or individuals.

Should You Be Concerned About Lightning Strikes Impacting Your Trees?

While lightning strikes are relatively rare occurrences, they are not as infrequent as many people might believe. Tall, isolated trees and those situated near water are statistically at a higher risk of being struck. Spotted Gums, like many eucalyptus species, are particularly conductive due to their moisture content and height.

If you notice a sudden or unexplained decline in a tree, especially following a storm, it is wise to have an arborist evaluate it at the earliest opportunity. Early intervention offers the tree the best chance for recovery and protects you from the dangers associated with a compromised tree that remains undetected.

Detailed Overview of the Case Study Conducted

This assessment was conducted by Steve Brown, senior arborist at Waratah Professional Tree Care. Waratah has been providing arborist services across Newcastle and the Hunter Region since 1998. We proudly hold ISO 9001, ISO 14001, and ISO 45001 certifications through Global Compliance Certification.

Essential Questions and Answers Regarding Lightning Strikes on Trees

Can a tree recover after being struck by lightning?
Yes, some trees can recover from lightning strikes, particularly if the impact was a glancing blow and the damage to the cambium is limited to one side of the trunk. The potential for recovery hinges on the species, the tree's overall health before the strike, and the extent of damage to the conducting tissue. An evaluation by an arborist is essential for determining the prognosis, ensuring that appropriate measures are taken.

How can I identify if my tree has been struck by lightning?
Look for signs such as bark that has been blown off or scorched in a spiral or vertical pattern down the trunk, entry and exit wounds, sudden dieback of the canopy in the weeks following a storm, and in some cases, split wood or shattered branches. The presence of Lichtenberg figure burn patterns on the bark is a definitive indicator of lightning damage.

Is a tree that has been struck by lightning dangerous?
Yes, it can be. A tree that has sustained significant internal damage from a lightning strike may fail structurally without exhibiting obvious external signs of distress. If you suspect lightning damage, it is crucial to have the tree assessed by a qualified arborist without delay to ensure safety.

What actions should I take if I suspect my tree has been struck by lightning?
Ensure that people and pets are kept at a safe distance from the affected tree until it has been evaluated. Contact a qualified arborist as soon as possible to assess the situation. Avoid attempting to assess the structural damage yourself, as internal damage may not always be visible from the outside and could pose a risk.

If you have a tree that you are concerned about after storm damage or a lightning strike, Waratah Professional Tree Care provides onsite assessments across Newcastle and the Hunter Region starting from $110.
Contact us at (02) 4956 6602 for a professional evaluation.