Tulip Poplar Wind Damage

Native to the moist, wind-sheltered woodlands across the eastern United States, tulip poplar (Liriodendron tulipifera) is often considered a weak-wooded tree. Trees are less sturdy and resilient when stressed by drought, insect pests or fungal diseases or when poorly anchored in soft, wet soils. While heavy snow or ice often causes large limbs to collapse, thunderstorm gusts can put extreme weight loads on poorly structured limbs, causing breakage or toppling the entire tree.

Significance

When the tulip poplar is young it grows with a cone-like structure. This arrangement naturally distributes branching and weight from foliage and wind more evenly: Larger and stronger branches are lower in the canopy and are supported by the trunk. As these trees mature, the form becomes more irregular and oval, with horizontal branching.

Wind Damage Susceptibility

Horticulturists with Iowa State University rate tulip poplar as an "intermediate" when it comes to susceptibility to storm damage. It's neither prone to wind damage nor resistant, though it becomes more prone to damage when improperly maintained or pruned poorly. The U.S. Forest Service comments that slender tulip poplar trees are often harmed, as are the top growth, called leaders, on trees. Keep in mind that any gust of wind wreaks havoc on trees when the physical strength of branches can't handle the stress.

Effects

Depending on strength of storm winds, the damage sustained by a tulip poplar ranges from mere leaf and twig debris to broken limbs or snapping off of branches at their junction with the trunk. Cracking fractures occur in strong, twisting winds.

Evaluation

Iowa State University recommends any tree that sustains injury -- splitting or removal of more than one-third of the circumference of the bark -- are most likely best fully removed. When the top erect leader branch is broken on large trees, the later regrowth may compromise the structural integrity of the tree and lead to further damage in storms. Young trees tend to recover better when the leader is broken and good training in the form of pruning occurs to re-establish a well-structured tree. All wounds on a tulip poplar tree increase opportunities for pests and diseases to infiltrate the vascular tissues.

Repair

Large tulip poplars require equipment and resources supplied by professional arborists. On trees that are small enough for decent access by homeowners, Iowa State University suggests immediate pruning is warranted after wind damage happens. Make any repair pruning cuts as small and as clean as possible; do not use wound sealants or pruning paints. Pruning saws make cutting branches easier as long as the cutting teeth are sharp. Never cut branches flush to their point of attachment; instead maintain the swollen collar at the base of branches and cut into the stub. This creates a small, more circular wound as compared to an oval wound once the collar is compromised. The U.S. Forest Service states tulip poplars usually make excellent and fast regrowth recovery after windstorms, but repeated damage inevitably causes an irregular, unhealthy or poorly growing tree.

Prevention

Pruning a tulip poplar when its younger than 15-to-20 years of age, creates a balanced branching structure. Begin pruning trees two-to-three years after planting them, according to Iowa State University. Small trees yield smaller pruning cut wounds and continue to grow branches that are the best positioned and angled as chosen by the gardener. A key concern is removing crossing, rubbing, inward-growing or diseased branches in the top of the young tree to ensure a perfectly shaped tree later in life, making it more resilient to winds.