Tags

, , , , , , , ,

dsc_0037

D dilitata

Still high up on the hill above Dare Valley Country Park, fresh growth of yet more species of fern.

This one is 3-pinnate and more or less triangular in outline with young indusia that appear curved to reniform. Merryweather (2007) works very well as the plant is clearly 3-pinnate and there is a very useful table on page 80 that draws out the salient points for each of the Buckler ferns. This one appears at first to have uniform pale scales but the ones closer to the base of the petiole do have a slightly darker stripe through the centre which identifies the fern as Broad Buckler fern Dryopteris dilitata. Hutchinson and Thomas note

‘Immature looking forms of D. dilitata exist particularly in sheep-grazed upland areas round the bases of outcropping rocks, usually less than 30cm and with scales without any dark central venation. They have often been wrongly recorded as D. carthusiana. The broad triangular outline to the frond indicates D. dilitata.'(p. 133)

dsc_0039

Triangular upland form of D dilitata?

Interestingly the fern has minute stalked glands on the leaf surfaces and the mid rib and down turned leaf edges. This is in contrast to Dryopteris aemula which has upturned pinnule margins, sessile glands and dark petiole.

dsc_0068

D carthusiana

In order to provide comparison here is another Buckler fern, Dryopteris carthusiana. This has 3 -pinnate leaves but has uniform coloured scales and the lowest pair of pinnae are shorter than those above it. The leaves are more parallel sided than D dilitata.

DSC_0052.JPG

D oreades

Another member of the Buckler fern family. It is a male fern and lacks the dark junction to the rachis which makes it either Dryoperis filix mas or Dryopteris oreades. This one has minute glands on the stem and the edges of the indusium suggesting it is Dryopteris oreades Mountain Male Fern according to Stace (1997).

dsc_0064

Polypody

In amongst some of the scree slopes are small numbers of Polypody. These are probably going to be Polypodium vulgare or Polypodium interjectum and may require microscopic examination to confirm identification.

Advertisements