The wildlife and wild places of Leicestershire and Rutland
- Ferns & Horsetails
Ferns & Horsetails
All images on this website have been taken in Leicestershire and Rutland by NatureSpot members. We welcome new contributions - just register and use the Submit Records form to post your photos. Click on any image below to visit the species page. The RED / AMBER / GREEN dots indicate how easy it is to identify the species - see our Identification Difficulty page for more information. A coloured rating followed by an exclamation mark denotes that different ID difficulties apply to either males and females or to the larvae - see the species page for more detail.
Ferns & Horsetails
Adder's Tongue & Moonwort
Horsetails are the relicts of an ancient family that once included tree-sized species, the fossils of which formed huge coal deposits.
Underground rhizomes produce numerous aerial stems; the stems and branches appear jointed and there is a ring of sheaths modified from leaves at each node. The size of the hollows inside a stem, the appearance of the sheaths and the number of stem ridges/sheaths are all used in identification. Cut through a stem-internode with your thumbnail to check and photograph the arrangement of hollows in the cross-section.
The spores are borne on cones at the top of the stems - sometimes on a separate brown or whitish stem.
- fertile cones
- large cone
- Dark light dark pattern of sheath
- Simple structure. Stems feel rough
- Drooping branches that are branched themselves.
In this family are our commonest large woodland ferns - the Male ferns, Buckler ferns and Shield ferns, with pinnate leaves, growing from underground rhizomes. Growth is usually in tufts or shuttlecocks, and they have scaly stems or 'rhachis' and large leaves or fronds divided on either side of the rhachis into leaflets, called 'pinnae'.
The 'sori' underneath the pinnae carry the spores. They are either side of the midrib and are rounded, with a cover or 'indusium'. This is kidney-shaped in Dryopteris and round with a central stalk in Polystichum.
The degree to which the pinnae are divided is a helpful diagnostic character, but the terminology can be confusing - and identification guides may have different interpretation of the amount of frond division. The pinnae may be sub-divided again into 'pinnules', and then divided again into 'pinnulets'. Sometimes this is called '1-pinnate', '2-pinnate' and '3-pinnate', or 'bi-pinnate' and 'tri-pinnate'. Sometimes the pinnae are partly divided, with lobes that may be deeply cut, but don't go right down to the midrib of the pinna; this is called 'pinnately lobed' or 'pinnatifid'. If the lobes are cut down to the midrib, they are called 'pinnatisect'. Some specimens are intermediate, and it can be difficult to work out the type of leaf-division. Immature fronds may be less divided than adult fronds, and the lower or upper parts of the fronds are often uncharacteristic - so always look at the central part of a mature frond.
Dryopteris have rounded lobes; Polystichum have acutely pointed lobes drawn out into 'whiskers'. Lady Fern (Athyrium filix-femina) is similar, with finely divided leaves, but is in a different family with 'C' or 'V' shaped sori.
- 1st record for VC55