Manitoba Maple
Acer negundo
Active Threats to Manitoba Maple
Maple Tar Spot
Common fungal disease causing black spots on maple leaves. Mostly cosmetic and does not seriously harm healthy trees.
Signs to watch for:
- •Black tar-like spots on leaves
- •Yellow halos around spots
- •Early leaf drop in severe cases
Recommended Action: Rake and dispose of fallen leaves in autumn to reduce spores. No treatment typically needed.
Free consultation available
Overview
Native but considered weedy and undesirable for landscapes. Fast-growing pioneer species
Commonly planted in prairie regions (hence Manitoba Maple) for quick shade, less common as intentional planting in Eastern Ontario
Identification
Leaves
Unusual for a maple - compound leaves with 3-7 leaflets arranged like an ash tree. Opposite arrangement confirms it's a maple.
Bark
Young bark is smooth and pale, developing narrow furrows and interlacing ridges with age.
Flowers
Male and female flowers on separate trees. Male flowers are clusters of red stamens, female are greenish.
Fruit
Paired samaras forming V-shape, produced abundantly on female trees. Can create litter problem.
Growing Conditions
Climate
Extremely adaptable to wide range of conditions including extreme cold, drought, and poor soil
Hardiness Zones: 2, 3, 4a, 4b, 5a, 5b
Light Requirements
Soil
Moisture: dry, moist, wet
Drainage: well-drained, moderate, poor
pH Range: 4.5 - 8
Tolerance
Care & Maintenance
Pruning
Best Season: October-March
Frequency: Regular structural pruning needed due to weak wood
- Prune in October-March (late fall to winter)
- Remove weak crotches and crossing branches
- Establish strong structure when young
Avoid: Spring when sap flows heavily
Watering
Establishment: Weekly watering for first year
Mature: Extremely drought tolerant
Seasonal Care Timeline
Spring
- Heavy seed production on female trees
- Storm damage common due to weak wood
- Aggressive seeding and sprouting
Summer
- Box elder bugs present
- Weak branches break in storms
- Heat and drought tolerant
Fall
- Box elder bugs congregate and may enter homes
- Leaf drop
- Storm preparation
Winter
- Weak branches break under snow and ice
- Remove hazardous branches
- Consider removal and replacement with better species
Common Issues
Weak Wood and Structure
HighNaturally weak wood prone to breakage and poor structure
Symptoms: Branch breakage, Splitting at crotches, Storm damage
Treatment: Regular structural pruning, remove hazardous branches
Prevention: Develop strong structure when young, ongoing maintenance
Professional arborist recommended
Box Elder Bug
LowInsects that feed on seeds and invade homes
Symptoms: Red and black bugs on tree, Bugs entering homes in fall
Treatment: Control is difficult and often unnecessary
Prevention: Remove female trees that produce seeds
Quick Facts
When to Call an Arborist
Recommended inspection: Annual inspection essential due to weak wood
- •Cracks at branch unions
- •Leaning or structural defects
- •Large dead branches
- •Tree near structures
- •Consider removal and replacement with better species
Free consultation for Belleville residents
Recommended Services
Based on Manitoba Maple characteristics