Depends entirely on how it is done. Poorly executed lopping is one of the most common causes of tree stress and decline. Done correctly it is a legitimate and necessary practice.
Lopping involves cutting large branches or the tops of trees at arbitrary points along the stem rather than at the natural growth junctions that allow a tree to seal over a wound effectively. When a branch is removed at a collar — the slight swelling where a branch meets the trunk or a larger limb — the tree can initiate a biochemical response that closes the wound over time. When a branch is cut in the middle of its length, that closure mechanism does not exist. The exposed wood is vulnerable to fungal colonisation, insect entry, and the gradual onset of structural decay that can work its way inward to the main stem over years.
The Long-Term Consequences of Poor Lopping
The long-term consequences of lopping are well documented and visible in trees throughout the Bay of Plenty that have been repeatedly lopped over the decades. The immediate response is a flush of fast-growing water shoots from below each cut point. These shoots are attached to the surface of the wood rather than embedded in the branch union structure the way properly grown branches are — they are mechanically weak and prone to splitting under load. As the shoots grow heavier over successive seasons, the risk of sudden failure increases significantly. A repeatedly lopped tree often becomes more hazardous over time, not less, despite appearing to be regularly managed.
When Lopping Is the Most Practical Option
There are situations where lopping is the most practical course of action, and an honest arborist will acknowledge this clearly. A tree that has been lopped multiple times may have lost the structural integrity needed to support proper pruning cuts at the original attachment points. In these cases the realistic choice is often between continued reduction and full removal. Similarly, trees that need to be kept significantly smaller than their natural form for powerline clearance or building proximity may require reduction cuts that approximate lopping in their effect, though these should still be made as close to laterals and natural junctions as possible to minimise long-term damage.
Better Alternatives to Consider First
Before accepting that lopping is the only option for your tree, it is worth getting an independent assessment of whether proper pruning or staged reduction could achieve the same practical outcome with substantially less long-term damage. In many cases a tree that appears to need heavy reduction can be brought back into balance through targeted deadwooding, crown thinning, and the removal of specific structural problems — leaving a tree that is safer and healthier without the stress response and ongoing hazard of a lopped canopy creating weakly attached regrowth.
When heavy reduction is genuinely unavoidable, the work should still be done by someone who understands the difference between an indiscriminate lop cut and a reduction cut made to a lateral that can take on the role of the removed section. The latter still causes some stress but gives the tree a better chance of managing the wound and redirecting growth in a less hazardous way. Tree surgery is not always about ideal outcomes — sometimes it is about the least-bad option, applied with real skill and an understanding of how the tree will respond.
Wahitapu Contracting takes an honest approach to every job. If lopping or significant reduction is genuinely the right call for your tree and your situation, we will tell you why and how to minimise ongoing risk. If better alternatives exist, we will explain those too. Call Kauri on 027 600 0446 for a straight assessment.