PSC 2620: Woody Trees and ShrubCourse HomeWeek 11

Acer grandidentatum - Bigtooth or Rocky Mountain Maple

Plant Viewer
Acer grandidentatum has three or five deeply cut rounded lobes. The margin has irregular serrations. The samaras are are held in a straight line with the seed held above. The wing turns papery brown before the seed does.
The bark is brown in color and has small ridges and furrows. In fall the leaves turn a bright mixtures of oranges and reds.

Plant Description

Acer grandidentatum, or Bigtooth Maple, is a small to medium tree or large shrub that grows natively in the hills and mountains of the intermountain west. It can grow to 30-40 feet high, but many specimens in the wild grow to only 25 feet. It is often found in a multi-stem form in the wild, but tree-form is available in limited quantities commercially. It has a spreading form, with a moderately dense canopy. It is widely adaptable to soil and moisture conditions, but will not tolerate a complete drought location.

The bark of the tree is a pale brown color. It has very slight ridges and furrows, and from a distance can appear as smooth. The samaras wings of the samaras are held in a straight line, with the seeds forming above it. The wings will turn a papery brown before the seed.

The leaf has three or five mildly rounded lobes (the small pair of lobes at the base of the leaf may not form) with and is deeply cut. The margin of the leaf has large, irregular teeth serrations. The has a palmate venation pattern which can be used to determine if the individual leaf has three or five lobes. The leaf is three-four inches wide and bright green. In the fall the leaves turn a brilliant orange or red color, clearly visible in the canyons during fall.

Landscape Use

The multi-stem form can be used in restoration projects or in naturalized plantings. It is also a good selection for incorporating into a wind block. The tree form is suitable for use as a parking strip tree or lawn tree. Plant it in masses to really take advantage of the fall color.

Points of Interest

Bigtooth Maple can be tapped for syrup like Sugar Maple can.