Norwegian Sunset Maple (Acer truncatum x A. platanoides 'Keithsform')
Pacific Sunset Maple (Acer truncatum x A. platanoides 'Warrenred')
The Norwegian Sunset & Pacific Sunset are so similar, they are considered here together.  Most notable is that the Norwegian Sunset is a little taller with more limbs, and the Pacific Sunset is a little shorter with fewer limbs.  Both of these trees appear to be fast growers, but with a moderate mature size, which is a nice combination.

The Norwegian Sunset has an upright oval form with good branch structure (wide angles) and uniform canopy. It has dark green glossy foliage that turns yellow-orange to red in the fall. The Northwest Shade Tree Catalog and Schmidt Nursery claim that the ultimate canopy size for this tree, grown for 30 years in average urban soil, will be 35' tall and 25' wide.

The Pacific Sunset has an upright spreading rounded crown form with a finer branch structure than Norwegian Sunset. The crown on the Pacific Sunset is said to be slightly shorter, at 30' tall by 25' wide. Summer foliage color is very glossy dark green, with fall colors turning yellow-orange to red a little earlier than Norwegian Sunset. They both appear to be very drought tolerant, showing little if any stress in the late dry summer.

Compared to most other maples, both the Norwegian and Pacific Sunset Maples exhibit a thicker, more leathery leaf. These trees also transplant relatively easily. In our nursery and in the landscape, both trees color a bit differently depending on location and the season’s weather. Unfortunately, some years the red, almost maroon, colored leaves tend to fall a little sooner than is desirable. However, I find their fast growth, summer and fall color, and limited height especially exciting and useful. In fact, the Pacific Sunset may be acceptable under, or next to, relatively high power lines. Please email me with thoughts about your own experiences with these trees.