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WSU/Pend Oreille Extension introduced the Sense of Place series in 1999, with a focus on place-based stewardship education. Since 2001, a partnership with the Kalispel Tribe of Indians Natural Resources Department (KNRD) has supported this newsletter and allowed us to expand class offerings through EPA funding. Further staff support comes through Renewable Resources Extension Act (RREA). Our newest partner, sponsor of the Rain Garden Challenge, is the Pend Oreille Conservation District. Many thanks to our partners and to you, our readers, for your continued enthusiasm for "digging" into the natural history and culture ofthis part of the world.

Improving with Age - Restoration Plantings


by Sandie Durand • Cascara Consulting

Compiling a long list of items that actually improve with age might be a difficult task these days; most seem to wear out, become obsolete or require continued maintenance to sustain their usefulness. Fortunately for soil stabilization projects there is a technique that can be added to the aforementioned list, Bioengineering. (Bioengineering can be defined as integrating living woody and herbaceous materials with organic and inorganic materials to increase the strength and structure of the soil. Allen and Leech 1997)

As landowners along the Pend Oreille River and its tributaries search for options to address stabilizing eroding shorelines, the term “bioengineering” is discussed through the Hydraulics Permit Application (HPA) process, which is included within the Joint Aquatics Resource Permit Application (JARPA). When soil stabilization is deemed necessary, an important benefit of implementing this type of stabilization technique is that it improves with age. Due to the integral vegetative component, this technique increases the soil binding capability as the aging root system grows deeper, spreads out and interweaves to form a strong, living matrix. Diversity of plant species plays a key role in this ever-improving mix of root system and multi-layered vegetative canopy.

The following partial list of Pend Oreille native plants, in conjunction with native grasses, are typically recommended for restoration projects due to their soil binding capability, habitat value and historic presence within our river landscape.

Willow species Red-osier dogwood Serviceberry Black hawthorn
Chokecherry Cascara Oregon grape Douglas spirea
Black cottonwood Thimbleberry Kinnikinnick Alder
Hazelnut Wild rose Ponderosa pine Water birch
Common snowberry Russet buffaloberry Mockorange Red-cedar
Oceanspray Black twinberry Western larch Aspen
Mallow ninebark Bulrush Douglas maple White pine


Riprap, or rock armoring, is a familiar and ever-increasing sight along our shoreline development, but many of these stabilization projects are lacking a vital and permit required vegetative component, like willow and red-osier dogwood, which would increase their erosion control effectiveness, restore lost habitat value and soften visual impacts to the surrounding landscape. As an example, pre-soaked (5 - 7 days) willow whips can be placed in existing riprap or depending on site location, longer willow pole bundles (wattles) can be placed against the prepared, angled bank in a manner which then allows rock to be placed over the majority of willow pole length, while the base of the bundles rest in water even at low water levels. The willow will root and sprout along the entire length of the cutting, ultimately growing up through the rock area and providing substantial benefit to the soil stabilization effort, with a minimum of additional cost.

(Salix exigua ssp. melanopsis), commonly known as Coyote, Sandbar or Dusky willow, is an excellent native species for soil stabilization projects along our shorelines, as it establishes quickly, colonizes by wide spreading root system and is right at home with seasonal high-water flows. The growth habit of this particular willow is such that it achieves a mature height of approximately 12 - 13 feet and the graceful stems are supple enough to withstand the powerful forces of ice/debris flows and spring runoff current.

Native willow habitat supports wildlife species ranging from elegant butterflies to the large and ever fascinating moose. Dense thickets provide excellent hiding, nesting and thermal cover, while the leaves, stems, catkins and buds are browsed by wildlife species such as waterfowl, grouse, snowshoe hare, moose, deer and elk during various seasons. Beaver utilize willow for both food and building material. Leaf drop provides nutrients, which benefit our fish populations.

Traditional uses of willow have included fishing weirs, baskets, mats, twine/rope, dolls, pack boards, drying racks, and fuel.

Including native plants that produce both soft mast (berries) and hard mast (nuts) in restoration projects encourages a greater diversity of wildlife usage, which is a principal goal as we try to replicate specific habitat types. Pend Oreille has one true nut producing plant which is valued not only for those tasty nuts, but also for the leaves, catkins, stems and soil stabilizing root system: Beaked hazelnut.

(Corylus cornuta) Beaked hazelnut is a sprawling deciduous shrub reaching up to 10 feet in height with multi-branching form. The spreading rhizome growth habit supports the soil binding capability, while the brushy thickets offer excellent protective cover for wildlife. The nuts, enclosed in light green bristly husks, grow alone or in clusters of two to three near the end of the twig. The drooping male catkins are prominent in winter.

Along with humans, pine and northern flying squirrels, chipmunks, both black and grizzly bears and the Steller’s jay all harvest the savory nuts. Deer browse the leaves and twigs. Winter finds rodents and snowshoe hare nibbling stems/bark, with ruffed grouse foraging on buds and catkins.

Various traditional uses of hazelnut have included food/trade items, baskets, spoons, fish traps, fishhooks, blue dyes and rope.

I encourage all interested landowners and contractors to research bioengineering techniques through upcoming workshops, visiting Kalispel Tribe demonstration sites and by talking to agency resources.

Let’s “Branch Out” in Pend Oreille County…Improving with Age!

Sources:
USDA-NRCS Plant Materials Center TN # 21 (Boise, January 2008) Planting Willow and Cottonwood Poles under Rock Riprap
USDA-NRCS Plant Materials Center - MT TN# (36) (February 2001) Users Guide to Description, Propagation, and Establishment of Native Shrubs and Trees for Riparian Areas in the Intermountain West
USDA-NRCS Plant Materials Center - (May 1998) Interagency Riparian/Wetland Project. The Practical Streambank Bioengineering Guide




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