The Crawfordsburn Fern
A significant botanical discovery was made in the Crawfordsburn Estate in the 19th century, almost certainly on land that is now within the Country Park.
A plant, which came to be called the Crawfordsburn fern, was discovered on the Estate in 1861 by one of the Sharman Crawford workers. It is understood that only a single plant was then found. The then Miss Crawford had her name attached to the discovery. The Latin name is Polystichum setiferum DivisilobumCrawfordiae (or Crawfordianum). It is a variety of the Soft Shield-Fern.
We know that fronds were collected in 1864 by William Hooker Ferguson, then director at Belfast Botanic Gardens, and were shared with the National Botanic Gardens at Kew. The second half of the 19th century was the era of the fern craze – pteridomania. This included not just the identification of new species in the wild and the development of cultivars, but also the creation of ferneries, like the one in Belfast’s Botanic Gardens.
The Crawfordsburn fern is notoriously hard to propagate, because unlike most ferns, it does not do so by shedding spores. The technique requires layering under the right conditions.
One expert commentator has said that the find of the Crawfordsburn Fern was very significant and paved the way for others. The Ferns of Ulster, written by two distinguished Holywood residents, William Henry Phillips of Lemonfield and Robert Lloyd Praeger, and published in the Proceedings of the Belfast Naturalists Field Club Appendix 1, volume 2, in January 1887, lists about 50 varieties of Polystichum setiferum. The authors called the Crawfordsburn Fern ‘one of the most beautiful of a beautiful class’, but warned that:‘the plants usually sold as Crawfordsburn Ferns in the market are a far commoner form, viz. Divisilobum Alchinii. The genuine plant is found in very few collections; it is easily recognisable by the very broad and overlapping character of the pinnae and the extreme breadth of the fronds’.
A number of residents in the local villages have growing in their gardens examples of what they believe to be a Crawfordsburn Fern; this was reputedly thanks to the Sharman Crawfords’ last head gardener and a fellow Estate worker, who rescued examples after Colonel Sharman Crawford had died. (Another resident had one which she believed was the real article, the provenance being from her grandmother in 1904.)
Contact has been made with a range of fern experts, both in Northern Ireland and in Britain. The identification of Divisilobum Alchinii for some of these specimens has been made, but the experts are still not absolutely convinced that we have one of the Crawfordiae variety. While arrangements have been made to ensure that one specimen which does appear to meet the criteria is cared for in a discreet place, DNA testing of the plant in the Kew herbarium and Northern Ireland candidates would help to be sure.