Monday, April 15, 2013

Acer rubrum - Red Maple

The red maples are a very popular landscape tree, especially with people from other colder areas. They are large deciduous trees, extremely variable in leaf shape as well as their growth habit. ( I am going to include the hybrids with silver maples in this group though they are a distinct species A. x freemanii but are difficult to distinguish from red maples.)

Why so popular? The picture below is why people plant them. Beautiful red fall color. The 'Red Sunset' Maple is one of the most commonly planted trees.



The species are for the most part large, 40-65'. Young trees tend to be quite pyramidal. Branches become ascending with age and develop into a rounded tree are maturity.

Here is another shot of a fairly typical specimen, but its in full bloom.



Leaves are either 3 or weakly 5 lobed, and which you see depends on the cultivar you are looking at.  The margins of the lobes are finely serrated and the sinus is angled. Lower surface has a waxy bloom. Upper surface is dark green. Generally they have a pretty long red tinged petiole.



This image is from a publication in the Journal of Arboriculture from years ago, showing the variability of leaf sizes, lobes, and serration on the leaves.



Flowers are small, red and in large clusters blooming and setting seed well before the leaves emerge. You might actually notice the tree in bloom because of its red or pinkish colored flowers.


Fruit is a pair of winged samaras, small .75" long with 60 degrees between the wings. Mature very early, usually red in color and fall by early summer.




Young stems are brown with lenticels. Terminal buds are clusted much like A. saccharinum. Older stems are gray to silver colored.


Many cultivars exist. Red Sunset (Franks Red) and October Glory are very popular but so are many others. See the columnar ones at the shopping center on Mt. Herman Rd in Scotts Valley (though they topped them last year).

Misidentification? Other maples perhaps. If you encounter one of the columnar forms of A x freemanii you might think its a silver maple only because of the leaf.

Locations:
Aptos: 409 Townsend - 3 fast growers, just recently "pruned" not sure which cultivar to be honest. 
Santa Cruz : 931 Mission Blvd. are a pair or decent looking ones.

Pleasure Point: 558 35th

Scotts Valley : Mt Herman Rd at the shopping mall at the CVS/McDonalds end by the road. These are columnar forms, most likely 'Armstrong'.

Edited 5/24