'Autumn Blaze' Maple Problems

Sap Rot

• Sap rot, also known as heart rot, is a wood decay condition caused by parasitic fungi. The invading fungus decays the wood of trunks, limbs and branches from the inside out, killing sapwood storage and conductive tissues. It also significantly reduces wood strength, which creates the risk of heavy, deadly limbs unexpectedly breaking off and falling. By the time limbs fall or other signs of infection are seen -- link conks or mushrooms, the fungi's reproductive bodies -- the damage is extensive. If sap rot-infected trees present the risk of falling limbs, they need to be removed. Maples are susceptible to a variety of fungi, including artist's conk, sulphur fungus, oyster mushrooms, parchment fungus, turkey tail, hairy turkey tail and varnish rot fungus. Varnish rot fungus, in particular, can quickly kill maples.

Physical Damage

• The Autumn Blaze maple is a cross between two soft-wooded maple species, making it more vulnerable to physical damage than are hardwood maples. Though this hybrid fairs better than the red maple under heavy ice and snow -- due to its silver maple adaptations of a strong central leader and wider crotch angles -- it is still prone to breakage. This breakage can create numerous problems, from a physical imbalance of the tree, to greater susceptibility to fungal, bacterial and pest invasions.

Chlorosis

• Silver maples, a genetic contributor to Autumn Blaze maples, are particularly prone to chlorosis and Autumn Blazes might suffer this condition due to a lack of iron. Chlorosis is a term used to describe a nutrient deficiency in trees -- often iron or maganese -- that produces yellow or yellow-green leaves, with or without discoloration of the veins and leaf scorch. In maples, this condition is often caused by acidic soils. If soil pH reaches above 7.0, nutrient deficiencies can occur in maples. Improper pH can also lead to a lack of symbiotic mycorrhizae fungi, which help the trees absorb nutrients.

Surface Roots and Rapid Growth

• Surface roots are a common issue with red and silver maples, along with their hybrids. Feeder roots from these trees often protrude above the surface, making turf growth impossible or inadvisable due to possible root damage from mowing equipment. Roots can be covered with organic mulch, but not soil. Autumn Blaze maples also are known for their fast growth rate. While an asset to newly established and young trees, it can become a liability if there is not enough space. Make sure to plan for a tree that can grow 60 feet tall and 40 feet wide.