Minnesota Tree Care Advisors

Characteristics
Disease Management

Boxelder is regarded as one of the "soft" maples and is a native tree in the wilds of Minnesota. Often Boxelder or Manitoba Maple is considered a weed species since it is commonly found seeding into fence rows and woodlot edges.

Medium tree height:		30-50'

Canopy spreads:		25-40', Rounded crown.

Drought Tolerance:		Tolerant

Shade Tolerance:		Intolerant

Soil pH Tolerance:		Tolerant to high pH

Poor Soil Drainage:		Tolerant to flooding

Salt Tolerance:		Sensitive to salt spray and Intermediate to soil salts.

There are a couple of varieties to be found in the nurseries: "Baron" and "Sensation" may be found. Boxelder is not a prized tree - it is considered to be messy and brittle and is a host for the boxelder bug. However, the tree is a survivor and is tolerant of urban stresses. These qualities make it a candidate for areas where other trees tend to fail.

Did you know
Boxelder trees do produce a sap that can be used for maple syrup!

DISEASE		SYMPTOMS	MANAGEMENT
Anthracnose, Discula species and others	Fungi	Tan/brown/black spots and blotches develop on leaves during wet periods. Spring infections result in leaf distortion. Necrosis may follow the veins.	Rake up and destroy or compost fallen leaves. Promote tree vigor. Not seriously damaging to healthy established trees. CHEMICAL: Preventative fungicides should be applied beginning at bud break when deemed necessary. Bordeaux, chlorothalonil, fixed coppers, mancozeb, thiophanate-methyl or zyban.
Leaf spot, Phyllosticta minima	Fungi	Well-defined lesion on the leaf surface with a light-colored center and dark margin at maturity. Tiny black dots (fruiting bodies of the fungus) are often visible.	Rake up and destroy fallen leaves. Avoid wetting the tree foliage during irrigation. Promote tree vigor. Seldom damaging to healthy, established trees. CHEMICAL: Treat preventatively with Bordeaux 8-8-100, fixed coppers or mancozeb.
Target-shaped canker, Nectria galligena, Eutypella parasitica	Fungi	Perennial cankers develop around wounds on immature trees, usually within 10 feet of the ground. The trunk is swollen around the canker, which often has a ãtarget-likeä appearance.	Plant on good sites in proper zone. Prevent damage to trunk and limbs. Promote tree vigor. Remove branches with cankers. May become a hazard tree and should be evaluated as such. CHEMICAL: None.
Tar spot, Rhytisma acerinum	Fungi	Roughly circular, raised black spots on the leaf surface which resemble spots of tar. Seldom a problem.	Maintain tree vigor. Infected leaves can be raked up and destroyed or composted. CHEMICAL: None necessary.
Wilt, Verticillium dahliae	Fungi	Slow growth, dwarfed foliage and/or wilting. Leaves with scorched margins. Defoliation. Often occurs on only one part of the tree. Green to black vascular discoloration may be present in the sapwood of larger branches and the trunk. REFERENCE: Verticillium Wilt of Trees and Shrubs, AG-FO-1164 (MN), Deciduous Tree Diseases, PP-697 (ND).	Fertilize to promote growth; keep nitrogen to a minimum. Prevent moisture stress. Remove dead limbs. Do not plant susceptible tree species where Verticillium is present in the soil. CHEMICAL: None. NURSERY: Preplant fumigation.