Re-introducing native plants to degraded land is an integral consideration in ecosystem restoration. Large areas of disturbed land are currently being revegetated with inexpensive and fast-growing domesticated grass and legume plants of European origin. While these species can 'green-up' and stabilize an area after disturbance, they frequently grow so aggressively that succession to native species is delayed or prevented. Native seed is not widely used for rehabilitating damaged ecosystems because it is costly, availability is limited, and little is known about the husbandry of native species.

       We have embarked on a program to collect, screen, and cultivate native grasses, sedges, legumes and other forbs in a manner which maintains their genetic integrity and which will make their seed available at competitive prices. Borrowing from tree seed orchard design, seed-increase plots have been established at two locations in the Bulkley Valley to produce easily harvested seed with broad genetic diversity. This multi-lineal seed is adapted to most locations between 52° and 60°N and between the Coast Mountains and the Rocky Mountains. It can be used directly for revegetation, or to establish additional seed increase plots. Using a combination of wild and plot-produced seed, we have established more than 158 test plots at 16 sites which have recently been impacted by industrial activities in northern B.C. Results from these widespread test plots will be used to refine seeding procedures, mixtures, and densities.

       This approach is a promising compromise between the use of locally collected native seeds and revegetation with cosmopolitan exotics.

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1. Large areas of land that have been degraded by logging, mining, road construction and other industrial activities are in need of revegetation. This project was undertaken with funding from Forest Renewal B.C. to develop supplies of native seed as an alternative to the European grasses and legumes currently used.

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2. Species were chosen for collection based on their abundance on disturbed sites. Over 900 accessions of 30 different grass, sedge and forb species have been collected over three years. Wild seed was collected from 52° to 60°N, from the Rocky Mountains to the Coast Range.

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Table: Seed accessions of major candidate species acquired to date in northern Interior B.C.

3. The origin of each unique accession was carefully recorded. Seeds were collected in paper bags, stored at room temperature, and later cleaned using soil sieves. Following germination tests, seeds were started in peat-filled styrofoam blocks and grown for 2 to 4 months in a greenhouse.

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4. Seedlings were transplanted into single-species seed-increase plots on land provided by Woodmere Nursery Ltd. (Telkwa, B.C.) and the Canadian Forest Service (at their Smithers, B.C., field station). Spacing of the seedlings was standardized using templates of 10, 20 or 30 cm, depending on the mature stature of each species.

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5. There is obvious morphological and phenological variability within species collected from diverse locations. To quantify and to establish the importance of inter-population genetic differences, Mr. Bryan Ie and Dr. Kermit Ritland (U.B.C. Dept. of Forest Sciences) are conducting electrophoretic and other tests on Elymus glaucus.

We invite population geneticists to conduct similar analysis on any of our species.

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6. A computer-generated planting layout was used in establishing the seed-increase plots. The layout was designed to maximize the possibility of out-crossing between accessions, thereby producing seed with the widest possible genetic diversity, while still adapted to a relatively narrow geographic range.

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7. The plants with which we are working are all perennials. Some plants have flowered and produced a bit of seed in the same year they were started, but most do not produce significant quantities of seed until their second year. Seed-increase plots range in size from 36 to 1,170 m².

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8. At this stage our plot-produced seed is harvested by hand or with a hand-held mechanized "seed stripper." As our plots increase in size, we will utilize other mechanical methods.

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9. Sixteen field seeding trials have been established across the Northern Interior on degraded landings and roadsides. These trials are evaluating different densities and mixtures applied in spring vs. fall. To date, plots have been prepared only by manual raking (or not all) and seeds have been spread by hand.

10. Monitoring of these plots is being conducted on an annual basis. Results to date have documented successful field germination of most grass, sedge and forb species, though high seeding densities (>500 pure live seeds/m²) are required. Preliminary monitoring suggests native plants are slow to establish but show good survival, indicating that short-lived cover crops may be a useful addition to most native seed mixes.