Black crowberry
Empetrum nigrum
Family: Ericaceae
Fire effect on plant
Black crowberry is top-killed by fire. Its underground parts may be killed by moderate through to severe fires (Foster 1985; Matthews 1992) .
Key traits
A low creeping shrub, that can form dense mats. Young crowberries have a strong deep penetrating primary root, but the rooting system expands as many lateral shallow roots form within the top 10 cm of the soil (Bell and Tallis 1973). Branches upon touching the ground can grow adventitious roots (Bell and Tallis 1973).
Seeds can survive fire with post-fire seedling recruitment seen, but it is not a regular occurrence (Lutz 1956). Seeds are animal-dispersed large distances.
Plant response to fire
Black crowberry grows in areas exposed to periodic burning of heather in UK. Some suggest that it increases in abundance directly after fire in these ecosystems before other taller shrubs re-establish (Gimingham 1964). Others class it as fire-sensitive (Sinker 1962), and it has been shown to decrease after fire in spruce forest ecosystems (Foster 1985). It has been suggested that this species can survive controlled burning or prescribed fires that are of low severity where the ground temperatures remain cool. But in wildfires of high severity, the shallow root systems will likely be killed (Bell and Tallis 1973). A study of the deep-burning wildfire on Howden Moor, South Pennines, UK in 1959 found that black crowberry took 12 years to begin to re-establish (Bell and Tallis 1973).
Timing of life history
Perennial species. Seeds likely produced from second growing season. Flowering May to June.
Conservation status
None.
References
"Bell, J. N. B., Tallis, J. H. 1973. Biological flora of the British Isles: Empertrum nigrum L. Journal of Ecology 61: 289-305. [Empirical evidence; Academic literature]
Foster, D. R. 1985. Vegetation development following fire in Picea mariana (black spruce) - Pleurozium forests of south-eastern Labrador, Canada. Journal of Ecology 73: 517-534. [Empirical evidence; Academic literature]
Gimingham, C. H. (1964). Dwarf-shrub heaths. The Vegetation of Scotland (Ed. by J. H. Burnett), pp. 232-87. Oliver and Boyd, Edinburgh. [Empirical evidence; Academic literature]
Lutz, H. J. 1956. Ecological effects of forest fires in the interior of Alaska. Tech. Bull. No. 1133. Washington, DC: U.S. Department of Agriculture, Forest Service. 121 p [Empirical evidence; Grey literature]
Matthews, R.F. 1992. Empetrum nigrum. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.usda.gov/database/feis/plants/shrub/empnig/all.html [Expert opinion; Grey literature]
Sinker, C. A. 1962. The north Shropshire meres and mosses: a background for ecologists. Field Studies 1: 101-38. [Empirical evidence; Academic literature]"