| BEN |
| BOTANICAL ELECTRONIC NEWS |
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| ISSN 1188-603X |
| No. 224 May 17, 1999 | aceska@victoria.tc.ca | Victoria, B.C. |
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Ethnobiologist Dr. Nancy Turner will receive the Order of British Columbia June 17 in a ceremony at Government House.
"Nancy Turner, a professor in University of Victoria school of environmental studies, has an international reputation for her scientific work. She has donated more than 25 years to documenting the endangered knowledge of First Nations groups, focusing on their interactions with the ecosystem for food, medicine and other material." [See also BEN # 173: "Professor Nancy J. Turner received 1997 R. E. Schultes Award."]
Congratulations, Nancy!
P.S. Jean Jaques Andre is another 1999 recipient of the Order of British Columbia. He worked with the B.C. Provincial Museum (now the Royal B.C. Museum) and designed most of their exhibits.
The Loomis Forest Fund, launched to protect 25,000 acres of rugged and pristine state-owned land near the Canadian border, aims to raise $13,1 million by July 1 to purchase and protect it from logging. The Loomis Forest, a largely roadless area in northern Okanogan County, Washington, is a popular recreation area that is host to numerous wildlife species, including grizzly bear and the largest U.S. population of Canada lynx in the lower 48 states.
Washington State's Common School Construction Trusts use the sale of logging rights on state land to finance school buildings. Money raised by the Loomis Forest Fund would be deposited in the trust fund and can be used for that purpose.
The campaign has raised $6.6 million in six months towards the goal of $13,1 million needed by July 1 to purchase the forest. About 3,500 contributors have given to the Loomis Forest Fund. For more information about Loomis Forest Fund, call 206-264-0477 or visit the campaign Web page at http://www.loomisfund.org/
[This paper was presented on the "Helping the Land Heal" conference and published in the Conference Proceedings:
For example, in the Intermountain Region of western United States, just south of the south Okanagan in British Columbia, the alien invasive annual grass, downy brome (cheatgrass, Bromus tectorum), has become dominant in habitats normally occupied by shrubs such as sagebrush (Artemisia tridentata) and antelope bitterbrush (Purshia tridentata) (McArthur et al., 1990). These shrub-steppe ecosystems with fire cycles normally upwards of 50 years, have turned into annual grasslands with a fire periodicity of 1-3 years. Downy brome matures by June and leaves a flammable stalk that can easily be ignited by lightning during thunderstorms in the summer drought. Shrub establishment has been inhibited and large expanses of habitat necessary to shrub-steppe wildlife has been lost. In addition, downy brome competitively excludes other native species by rapidly monopolizing early spring moisture reserves, often the only source of moisture available to germinating seeds and young seedlings (Melgoza et al., 1990).
In 1993, a fire occurred in the south Okanagan that made us rethink the interaction of fire with downy brome, in that here the wildfire event eliminated downy brome from intensely burned plots. This enabled establishment of the perennial bunchgrass needle-and-thread-grass (Stipa comata) in ungrazed plots, and the perennial sand dropseed (Sporobolus cryptandrus) in grazed plots.
The fire occurred through Ecological Reserve 100, otherwise known as Haynes Lease Ecological Reserve. We would like to thank BC Parks and associated personnel, especially Judy Millar, for letting us do this project in the Ecological Reserve. The wildfire occurred on July 9, 1993 with varying degrees of severity. There was a strong fenceline effect. Areas outside of the Ecological Reserve did not burn as severely because they were heavily grazed by cattle and did not have much plant material to burn. We documented five classes of burn severity based on how much remained of above ground vegetation: 1) unburned, 2) lighter than light (only on grazed side) - some herbs such as Antennaria spp. survived the fire, 3) light - some resprouting of shrubs and herb layer, 4) moderate - burned, but still standing shrub layer, and 5) intense (only on ungrazed, Ecoreserve side) - totally blackened and falling shrub layer.
Plant re-establishment following the fire was documented in 298 small (20 X 50 cm: Daubenmire, 1959) permanent plots.
Plant density (number of individuals per species per plot), and percent cover were measured in June of 1994, spring of 1995 and June of 1997. Forty species of plants were found within all plots just one year after the wildfire. In a multispecies analysis (using Canonical Correspondence Analysis: CANOCO), both cattle grazing and burn severity affected the distribution of plant species.
In general, perennial grasses needle-and-thread grass (Stipa comata) and Sandberg's bluegrass (Poa secunda) were associated with more intensely burned plots along with herbaceous perennials long-leaved phlox (Phlox longifolia), pale comandra (Comandra umbellata), and the shrub smooth sumac (Rhus glabra). Disturbance adapted plants such as the weed Russian thistle (Salsola kali), the native annual evening star (Mentzelia albicaulis), and the perennial bunchgrass red three-awn (Aristida longiseta) were associated more with the grazed section than the ungrazed Ecological Reserve. Interestingly, even though downy brome is associated with fire in the Intermountain West, we found that at our plots, it was more associated with plots that did not burn, or that did not burn severely. Upon analysis of the density data of this individual species, in the year following the wildfire, downy brome was virtually eliminated from the most severely burned plots, while remaining high in density in the unburned plots. Lightly and moderately burned plots also had fewer individuals. In 1995 the downy brome population was starting to reestablish in the burned plots, but the intensely burned plots still had far fewer individuals than the unburned plots. This was especially so in the ungrazed Ecological Reserve. In the grazed burned areas outside of the Ecological Reserve the elimination of downy brome lasted only one year. By 1997 downy brome had reestablished in all plots so that there was little difference between unburned and intensely burned plots.
Though we did not measure seeds in the seedbank to test whether the wildfire eliminated viable downy brome seeds, other research in similar areas suggest this is so. Hassan and West (1986) showed that downy brome seeds were reduced by half in burned plots, and that the effect was highly significant in more severely burned plots. Similarly, under experimental conditions, heating soil reduced emergence of downy brome seedlings as compared to unheated soil (Blank et al., 1994). The heat of the fire would not have to penetrate deeply because there is evidence to suggest that a downy brome population is established from the previous year's seeds. The seeds largely do not remain viable in the seed bank after the first year (Crist and Friese, 1993).
The apparent contradiction between these and our results and the conversion of shrub-steppe habitat to fire susceptible annual downy brome grasslands, can be explained by fire temperature. More frequent fires burning grass would not burn as severely as those that burned shrub-steppe, because the fuel loading would be reduced. Cooler fires would not burn as many downy brome seeds. Perhaps one way to get rid of downy brome in the sites where it now dominates would be to add fuel to the system, and then plant native seeds if none remain.
Our data showed that after the wildfire, the two to three year window of reduced downy brome density resulted in establishment of native perennial bunchgrasses. In the ungrazed Ecological Reserve, needle-and-thread grass was initially absent from unburned plots, the same ones that were dominated by downy brome. In the first year following the wildfire, seedlings of needle-and-thread grass emerged in the burned plots, especially so in the moderate and intensely burned plots; again, the same plots now without downy brome. Percent cover of needle-and-thread grass more than tripled between 1994 and 1997 (from less than 2 % to over 6 %), while density increased only slightly in the intensely burned plots (from 0.7 to 1.0), indicating that small individuals germinating in 1994 survived and grew.
In the plots grazed by cattle, sand dropseed (Sporobolus cryptandrus) benefitted from the one year gap left by downy brome, but not to the same extent as needle-and-thread grass under ungrazed conditions. Sand dropseed is known to be a native bunchgrass that is disturbance adapted and is considered an increaser, so it is not surprising that sand dropseed was more abundant on the grazed plots, and that it also responded well to the wildfire. Moderately burned plots had the greatest number of sand dropseed individuals, especially just after the fire, but lightly burned plots had the greatest cover of sand dropseed. Over the three years, number of sand dropseed individuals decreased in moderately burned plots from an average of just under 4.5 per square meter in 1994 to just under 2.5 individuals in 1997, suggesting that many new seedlings did not survive. Percent cover increased slightly from 5% to just over 7 %. In lightly burned plots, density was lower (2.5 individuals per square metre in 1994 to 2 in 1997), but percent cover was highest (14.5 % in 1994 to 18.5 % in 1997), suggesting that the individuals were largely resprouting from already established root stocks.
These results suggest that hot summer fires can be beneficial to the restoration of south Okanagan grassland communities, especially under ungrazed conditions. Downy brome may be eliminated for a long enough period of time to permit seedling establishment of native perennials if the fire is severe enough to burn or kill downy brome seeds in the seed bank.
References:
In spite of its geographic area (Ontario, eastern Canada and NE of the U.S.A.) this book is an important addition to the identification guides even for our area. 875 superb colour photographs illustrate over 600 species of fungi. Dr. Barron estimated that about 500 of these species also occur in western Canada. The author has included slime moulds (Myxomycota), and has paid more attention to mushrooms of "lesser interest" such as "sac fungi" (Ascomycota), jelly fungi, coral and tooth fungi, and bracket fungi. Dr. Barron paid special attention to small mushrooms and his photographic skills are remarkable. Look at Mycena epipterygia (p. 287) or Mycena rorida (p. 283)!
You should also visit Dr. Barron's web page
for examples of photographs published in this book.
The book is well organized. Thumbnail pictures on the back cover, and several pages of thumbnail pictures at the beginning of the book take you quickly to a particular group of fungi. Six keys in various parts of the book help with the identification of those genera where one cannot get a reliable identification just by matching pictures with an unknown mushroom.
The book is very well produced and both the author and the publisher should be congratulated for their achievement.