Subject: -Holly Trees (DEGRADE) bird habitat (distinguish from Oregon Grape)
Date: Feb 22 20:47:23 2004
From: Stewart Wechsler - ecostewart at quidnunc.net


Kelly Cassidy writes:
Before you kill the holly, be sure it isn't Oregon Grape (genus Mahonia).
Mahonia, a native, has prickly, holly-like leaves.

If anyone wants to know how to distinguish Oregon Grapes form Holly here
goes:

The following is a good photo of a female English Holly Ilex aquifolium:

http://ispb.univ-lyon1.fr/cours/botanique/photos_dicoty/dico%20D%20a%20K/ile
x_aquifolium.jpg

Or the other images from google search:


http://images.google.com/images?q=%22Ilex+aquifolium%22&ie=UTF-8&oe=UTF-8&hl
=en&btnG=Google+Search

the following are images of Low and Tall Oregon Grapes, Mahonia/Berberis
nervosa and M/B. aquifolium

http://images.google.com/images?q=%22mahonia+aquifolium%22+OR+%22mahonia+ner
vosa%22+OR+%22berberis+aquifolium%22+OR+%22berberis+nervosa%22&ie=UTF-8&oe=U
TF-8&hl=en&btnG=Google+Search

English Hollies can grow to 60' tall and quite dense. Tall Oregon Grape
to 15' maximum and usually not that dense. Low Oregon Grape grows to 2 1/2
'. Holly leaves are simple. Oregon Grape are compound with 2-9 pairs of
opposite leaflets plus one terminal one. Tall Oregon Grape, Mahonia
aquifolium has 2-4 pairs and Low Oregon Grape, Mahonia nervosa has 4-9
pairs. Holly berries are red and not on spikes. Oregon Grape fruits are on
spikes (short on Tall Oregon Grape, and long on Low Oregon Grape) and are
dark with a light blue blush. The attractive yellow flowers on spikes of
the Oregon Grapes are starting to bloom now and may attract hummingbirds.
Surprisingly, Pileated Woodpeckers eat Oregon Grape fruits. The Tall
species M. aquifolium grows in drier sunnier sites by western Washington
standards, and Low Oregon Grape, M. nervosa is usually in more shaded sites
that aren't as dry.

Stewart Wechsler
West Seattle
mailto:ecostewart at quidnunc.net