Sycamore Maple, Acer pseudoplatanus, is a member of the soapberry family (Sapindaceae).
Sycamore maple is a native of Central and Southern Eurasia.
It was originally imported to North America in the 1870s as a horticultural tree for planting in urban areas.
The tree has been present in the wild in North America since the early 1900’s.
The timber from this tree species is widely used to produce building materials.
Sycamore maple can be used for its sugary sap in maple syrup production.
Sycamore Maple is a deciduous tree species that can reach 20m in height. It is a very adaptable species that grows in full sun or light shade, and tolerates some salt. It is native to Europe and western Asia.
Here are some key features that may help to positively identify Sycamore Maple:
Leaves are medium to large, broad, with a leathery texture, dark green above and light green below
Leaves have 5 lobes, with 2 outer lobes reduced, base of leaf is heart-shaped
Leaf edge is coarsely toothed
Bark is scaly and regularly flakes off mature trees, revealing an orange inner bark
Twigs: zig zag, stout, leaf scar nearly surrounds the bud, buds are large and cone-shaped
Flowers are small, greenish, and bloom in the spring in long, drooping clusters
Trees produce winged seeds (samaras) the form in clusters
What it does in the ecosystem
Sycamore maple is an invader of sensitive ecosystems such as woodlands, forests, and riparian zones.
It is a fast-growing tree, and is known to be a first colonizer at woodland edges, old fields, and roadsides.
The tree has high shade tolerance, allowing it to invade densely forested areas where as little as 1% of canopy light reaches the forest floor.
Sycamore maple produces an abundance of seeds each year.
Mature trees produce anywhere from 10,000 to 170,000 seeds (most of which are viable and can germinate.
Winged seeds or “samaras” allow for dispersal by wind up to 50m.
The bountiful seeds can create dense stands of seedlings that can outcompete native tree seedlings for space and nutrients.
Development of established stands in the wild can cause displacement of not only native plants but also the wildlife that depends on them for food and shelter.
Sycamore maple may not produce a viable nutritional replacement for wildlife.
Before selecting a control method, consider
The size of the infestation.
The amount of effort you are willing to expend.
Often, multiple control methods are used simultaneously.
Consider the local ecosystem and what other organisms or ecological processes may be affected by management.
Control methods for sycamore maple are not widely studied.
Since the tree is often found in sensitive habitats, it is important to minimize soil disturbance and impact on surrounding native vegetation and wildlife.
As sycamore maple is a prolific seed producer, it is a wise choice to begin management early in the spring before seed set.
Physical control of sycamore maple is generally considered to be a highly feasible option for management.
Young trees and seedlings can be dug up or hand-pulled, being careful to remove the root system with the plant while minimizing soil disturbance.
Mowing is an option to control groups of newly germinated seedlings, as they would be unable to regrow from left-behind roots.
Larger trees can be removed by cutting them down and either grinding the stump or returning to the site to cut down any new shoots that arise from the stump.
Larger trees can also be girdled.
Girdling involves removing a two-inch-wide ring of bark from near the base of a tree.
Remove the outer bark and the green cambium layer, but avoid cutting into the hard core of the trunk.
If the xylem layer in the core is disturbed the shrub will respond by resprouting. If the cut is not deep enough the tree will heal.
This is why it is key to cut to the appropriate depth.
This technique allows the roots to nourish the crown but prevents the crown from sending nourishment back to the roots, leading to eventual root death.
Trees that have been girdled should continue to be monitored and new sprouts that develop below the girdled site should be removed.
Girdling sizeable infestations is labour-intensive, so this method may not be feasible for large infestations.
Girdling should be reserved for large individuals that cannot be pulled or along waterways where it is the only species along the bank.
Girdling is best undertaken in the springtime.
You will need to return to the site to remove any shoots that may arise from the stump.
Physical control can be completed within a few years as seeds do not persist for long in the soil.
For the first few years, return to the site regularly to remove any seedlings or sprouts that arise from left-behind roots, stumps, and germinating seeds.
Chemical control methods for sycamore maple exist, but the PEIISC does not provide advice on chemical control measures at this time.
If using chemical controls, it is imperative that all local legislation and manufacturer’s instructions be followed during application.
As Sycamore Maple commonly invades sensitive habitats, chemical control may not be a sensible choice, as it can have unintended negative ecological consequences.
DISPOSAL AND REMEDIATION
Removal and disposal of sycamore maple can be facilitated by a wood chipper after roots have been allowed to dry out.
Ensure that no seeds or roots are transported offsite by vehicles, tools, or clothing.
Replanting the area with a variety of native trees and shrubs to increase biodiversity.
Plants such as sugar maple, red maple, striped maple, yellow birch, Eastern hemlock, red spruce, witch hazel, beaked hazelnut, and American fly honeysuckle can help the area to regenerate.