Amur Maple | Chautauqua Park in Boulder
Norway Maple | Chautauqua Park in Boulder
Norway Maple | Flower Cluster
Acer
Maple
These are a very popularly planted tree in landscapes along the front range. They grow medium to fast and there are many species big and small to choose from. The maples have long held a prominent position in our yards, parks and along many city streets. Predominantly Silver, Sugar and Norway maples have been the Acer species of choice. However grand and significant they’ve been, their presence paralleling the population growth of the west for the past one hundred years, we have discovered faults and phased many of these selections out in recent years. Luckily, thanks to modern advances in hybridization there are many new and auspicious options in maples available when color and tradition are commanded in the landscape.
Maples tend to have deficiencies of iron in the high PH soils of the front range and suffer from chlorosis as a result. Iron chlorosis shows up as a yellowing of the leaves and is often isolated to one side or part of a tree but can affect the entire canopy.
Some varieties of maple are predisposed to poor physical structure often resulting in disastrous limb and leader failure as the tree matures. Early structural pruning can be helpful and sometimes can establish an architecture sufficient to the plants long term survival.
Sun scald is common on young trees and where outer/upper branches have been removed or broken exposing the supple bark of previously protected limbs.
With most container or ball & burlap (B&B) plant material, we look for girdling roots which are fairly common in these trees and can be a huge issue if left to neglect and chance. While looking at the roots check for a root flare which should be discovered by digging if not readily apparent.
Maples have very few issues with disease along the front range. They are susceptible to Verticillium root rot when under stress. The most common stresses for maples are soil related. Also found during particularly wet and warm springs are the occasional fungal problem on the leaves of some maples.
Maples will sometimes succumb to an aphid population if stressed from poor soil or root conditions. Because the aphids are opportunistic or secondary they will hardly have a long term negative effect on the tree. More rarely we see mites on the leaves of this species as well.
They grow medium to fast reaching a mature height of 45’ and a canopy spread of 35’ with a generally rounded canopy shape and they like medium soil moisture. A cross between (hybrid) Silver and Red maple.
This cultivar has been very popular the past ten years most notably for its vivid display of oranges and reds in the autumn. They grow medium to fast reaching a mature height of 45’ and a canopy spread of 35’ with a generally rounded canopy shape and they like medium soil moisture.
These are a very popular tree planting in landscapes along the Front Range. They grow at a medium rate to a mature height of 50’ and a canopy spread of 40’ with a generally rounded shape and they like medium soil moisture. They typically display dark green, dense foliage that turns yellow or brown in the fall. They are often found struggling in dry soils and have difficulty with sunscald and leaf scorch.
There are a number of cultivars available of the Norway maple, the most popular is the ‘Deborah’ and the slightly smaller ’Royal Red’ which has dark red-purple foliage.
A fast growing tree with a mature size of 45’ X 40’ and a conical shape. A shade tolerant species flowering (red) early in the growing season and shutting down with red leaves in the fall. A challenging choice for the Front Range considering the difficulty this species has in alkaline soils.
Maturing to 45X35 with a round canopy they are considered a medium growth tree with a red to orangish fall foliage. Hardier than the other red maples.
Very similar to original red maple but tends to have a broader canopy shape.
Reaching 65’X50’ these trees are generally upright or rounded growing fast and they need high soil moisture to thrive. Red-orange fall foliage and prefer well drained soils.
Silver maples are a past favorite street and yard tree that have fallen from grace as their issues have played out in property damage. They tend to have surface roots causing problems with turf, sidewalks, driveways and streets. They have an affinity for sewer and water lines which comes at a great expense to those in stewardship of such infrastructure. Being fast growers they are poor compartmentalizers meaning that they often develop large cavities from decay as they mature becoming extremely hazardous to anything or anyone under their immense canopies.
A smaller and tougher variety of the Silver Maple that deals much better with dry soils and hot summers thanks to its waxy dark leaves.
A large tree reaching heights of 150’ in the northeast but typically 50’X35’ along the front range with an oval shape they are slow growers and need high soil moisture. These are the neon signs of the forests of the northeastern autumn. Absolutely spectacular fall colors make them a very popular landscape tree. Structural pruning early on life is important for this species do to mature into healthy trees.
There are a few cultivars available.
Maples have been and continue to be an important source of commercial grade wood and of course maple syrup from the Sugar Maple. They also have enormous economic significance in the northeast as they attract millions of visitors each fall who observe and photograph the incredible reds, yellows and oranges of the maples (especially the Sugar Maple!)
The Canadian flag is the image of a Sugar Maple leaf.