Summer ended early this year and September has been cold and wet here in Norfolk. This summer’s last hot, sunny days were at the end of August and on one of the hottest of these days (August Bank Holiday, 28th August 2017) we visited the Norfolk Brecks with our friend Ian. We took a train from Norwich to Brandon and a taxi to Cranwich Camp, and then walked back to Brandon station on some lovely tracks and paths.

One of the plants we had gone to see at Cranwich Camp was Spanish Catchfly, Silene otites.

Spanish Catchfly, Silene otites, at Cranwich Camp.

Spanish Catchfly, Silene otites, is a member of the Carnation family, the Caryophyllaceae. Silene is the biggest genus in the family, with around 700 species, and in the British Isles it includes the Campions and several other Catchflies. Silene is named after Silenus, a woodland deity in Greek mythology, companion and tutor to the wine god Dionysus.

Spanish Catchfly is a rare native plant in the British Isles, and it is a speciality of Breckland, where it grows on grass heaths and, in Suffolk, on some roadsides. Cranwich Camp, an area of SSSI grassland in west Norfolk, west of Mundford and south of the village of Cranwich, is one of the best places to see it. A Labour camp was set up on the site in 1935 and unemployed men from the north of England were housed there and made to do manual work in exchange for dole money. In World War Two the camp was used by the armed forces. In more recent years, the site was notified as a Site of Special Scientific Interest (SSSI) because it is home to several rare invertebrates and plants. The latter include Spanish Catchfly and Proliferous Pink.

Spanish Catchfly is a perennial plant, which forms a rosette of narrow, dark green leaves. Tall, narrow spikes of tiny, lacy, cream-coloured flowers occur from June to September – when we were there in late August, some had run to seed but others were still in bud. The plant is more or less dioecious – there are separate male and female plants, though the male plants sometimes bear a few hermaphrodite flowers, usually with only a vestigial ovary.

Male flowers

Female plant with seed capsules

Like several of its relatives, Spanish Catchfly has scented flowers, especially after dusk. Night-flying moths and mosquitoes are the main pollinators and the flowers emit a range of chemicals to provide their scent. It has been suggested that Catchflies’ sticky hairs may have evolved to prevent the theft of pollen by wingless insects climbing the stems.

Silene otites does best in an open grass sward. In denser grassland, the plants are eventually crowded out and the seedlings need disturbed ground to establish successfully.

Until the late 1990s there were thousands of Spanish Catchfly plants at Cranwich Camp, but a survey in 2007 found only 221 plants. Something had to be done and in 2011 turf was stripped from part of the site. The experiment was a success: by 2013 over 2900 plants were recorded in the stripped area. Spanish Catchfly was certainly abundant when we visited Cranwich Camp in August.

Spanish Catchfly is widespread throughout Europe and it is fairly common in eastern, central and southern Europe but very local in the northern parts of its range, including the British Isles. In the west its distribution extends from Iberia northwards to Britain, while the eastern edge of its range extends to Poland, the Caucasus, northern Iran and Siberia.