Subject: plants shelter
Date: Jun 16 12:55:05 2004
From: Kelly Cassidy - lostriver at completebbs.com


Teresa and any other readers interested in providing shelter,

The short answer is that any vegetation taller than mowed grass provides
better cover than a lawn. Here's the long-winded answer:

What you can do depends on how much space you have, how much of a gardener
you are (or want to be), the potential fire danger, and whether you have a
back yard out of sight of neighbors who might object to "brush and weeds."

It's instructive to drive around a typical neighborhood and look at the
arrangement of shrubs, trees, and herbaceous vegetation (i.e., non-woody
plants) and compare to the arrangement of these elements in a less
cultivated NW environment.

Shrubs in landscaping are most often used 1) as foundation plants along the
side of a building, 2) as a boundary delineator, placed in a narrow line, 3)
as a "specimen" plant placed alone in a lawn or in a perennial bed, 4) as a
hillside soil stabilizer (often low junipers).

In a less cultivated situation in the NW, shrubs are more often seen as 1)
the understory of an open-canopy forest, 2) a shrub patch or thicket, 3) a
linear arrangement along a distinct environment feature like a stream but
usually bordered by or mixed in with medium or tall herbaceous vegetation,
4) if isolated, usually among herbaceous vegetation taller than the standard
mowed lawn.

The typical cultivated situation provides minimal cover because the shrub is
isolated from other shrubs or from herbaceous plants and trees suitable as
hiding/foraging areas. To make them even more isolated, many gardeners keep
the ground at the base of the shrub as barren as possible with landscape
cloth and/or a gravel mulch. Similar problems occur with trees in a
cultivated landscape.

So (trying to keep this from getting too long winded), your shrub or tree
cover will be most valuable if you aim for one of the following:

1) a shrub patch, instead of a shrub line, either as a mix of many shrub
species or a stand of native species that typically forms patches. Between
the shrubs (which will take some years to fill in), a mix of grass and forbs
(non-grassy herbaceous plants) provides a sheltered foraging area so the
birds can move between shrubs and herbaceous vegetation without crossing
dangerous open space. This arrangement takes a lot of ambition and you need
to be a reasonably dedicated gardener to get things established and keep the
weeds out until the other plants are large enough to prevent new plants from
moving in. The cover value is greatly enhanced if fallen leaves are left in
place and dead plant part are left standing through the winter.

2) A broad perennial bed with a mix of plants (including grasses) left
standing in the winter, with shrubs placed within the beds.

3) Shrubs placed in a patch near a big tree or along a line of trees. (Note
that most shrubs should be placed at or beyond the drip line of a tree;
otherwise, the tree will be too much competition.)

These arrangements allow birds to go from tree to shrub or from shrub to
relatively protected ground to forage. It's nice to use natives, but most
wildlife isn't all that picky. There's a big emphasis in backyard habitat
literature on planting shrubs with fleshy fruit. Waxwings and robins have
undoubtedly benefited, but even they need other sources of food when the
fruit is not in season. Your plants also need to provide insects, other
invertebrates, seeds, and cover. The sources of food for the insects and
invertebrates are BOTH living and dead plant material. In fact, in many
ecosystems, the DEAD plant material is more important than the living as a
source of food and cover. IF FIRE IS NOT AN ISSUE, leave the dead branches,
fallen leaves, and standing dead material where it is.

Some caveats:

1.) In most neighborhoods, it's better to leave the front yard with a
"conventional" neat, tidy look to avoid irritating the neighbors.

2) Don't leave dead plant material near your house or structures to reduce
the fire and carpenter ant dangers. Don't leave a lot of brush or flammable
material near a road or walkway where a passerby with a cigarette could
easily start a fire.

3) A compost pile is better than bagging your leaves and having them hauled
away, but the wildlife gets more benefit from plant material left in place
than concentrated in a compost pile where nitrogen losses are high and much
of the invertebrate participation in decay is lost.

4) (This might stir up some objection) I personally think bird feeders are
incompatible with improving the habitat because they increase the problem of
human-dependent pests like Norway and Black Rats. "Domestic" rats, and
other animals strongly associated with people, rely on a combination of a
seasonally-independent food supply and cover. Seasonally-independent means
the quantity and type of food does not vary with the season. The native
animals are adapted to the seasonal changes in food supply. Without bird
feeders, they may suffer high mortality in bad winters or dry summers, but
their mortality will be lower than the species that are totally dependent on
the feeders. Most communities tackle the rat-control problem by addressing
the cover need aggressively. No junk piles, no wood piles near the ground,
no brush, etc. They attack the food issue by trying to keep garbage from
being too accessible. They don't try to control bird feeders and pet food
left outside because it's too hard and politically unfeasible. It's much
easier to control the cover. If you increase the cover in your yard with
brush and vegetation AND have a seasonally-independent food supply, you will
likely see an increase in the rat, raccoon, opossum, etc. population. To
avoid a rat problem, you can either have a feeder, but no cover or establish
cover but get rid of the feeder. Unfortunately, you can't control what the
neighbors do. If you have the cover and they have a feeder, you'll have a
rat problem.

I'm currently grappling with a lot of these issues myself in trying to
improve the habitat on my lot. In removing some of the flammable brush by
the road and aggressive weed control, I feel like I've made the habitat less
wildlife friendly than it was before, at least for the time being. Fire is
not the huge danger in western Washington that it is in eastern Washington,
but it is not insignificant.

To answer your simpler question about shrub species, if you plant a shrub
patch, I'd suggest a mix of species. As a gardener, I don't like prickly
shrubs, but a lot of birds like them for protection. I'm not a stickler for
natives but definitely avoid anything that might run rampant. Perhaps a mix
of roses (native if possible or a non-invasive shrub rose), salmonberry,
thimbleberry, hawthorn, one of the native wild cherries, Oceanspray
(Holodiscus), Devil's Club (Vicious ouchious, aka Oplopanax horridus),
Amelanchier alnifolia, Hazelnut (Corylus cornuta), elderberry, Pacific
ninebark (Physocarpus capitatus), etc., etc. Throw in a couple of showy,
rugged, low-maintenance cultivated shrubs if you don't want it to look too
wild. A path with a distinct border will also make things look more
planned. Hide the detritus out of sight if appearance is an issue.

Kelly (can't give a short answer) Cassidy
Pullman, WA