In the Voorsterbos, a planted woodland on a former sea-floor (the Netherlands), artificial gaps within stands of Fagus sylvatica on boulder clay were monitored for five or six years after cutting. Ten fern species and three species of horsetail established in these gaps, with Dryopteris cristata, Thelypteris palustris, Matteuccia struthiopteris and Equisetum telmateia not previously known from the Voorsterbos. Athyrium filix-femina was most successful and formed dense stands in some gaps. Two species (Gymnocarpium dryopteris, Dryopteris cristata) established but have since disappeared. Thelypteris palustris has built up a sustainable population. It seems plausible that the germination of ferns and horsetails took place during the first season following cutting of the gaps and was derived from a spore bank with an optimal microclimate with constant high moisture and humidity in the shaded part of the gaps. Competition from recruiting trees and shrubs was suppressed in some of the gaps for a period of five year through herbivory by Roe deer.
Cyathea sledgei Ranil, Pushpakumara & Fras.-Jenk. is a new tree-fern species from Sri Lanka, morphologically intermediate between C. sinuata Hook. & Grev. and C. hookeri Thwaites. It is easily recognised by its simple but deeply lobed leaves; each lobe has 8-10 pairs of forked veins and 6-9 pairs of sori. It was first recorded as a putative hybrid and the origin of this species is postulated to have been directly through hybridisation between the above two species. It behaves as a species, readily forming populations and apparently being fertile. C. sledgei occurs among populations of the two other species, C. hookeri being similarly restricted in occurrence. All three species are endemic to Sri Lanka, though Large & Braggins (2004) misreported C. sinuata from South India.
The presence of Dryopteris remota (A. Braun ex Döll) Druce in Poland was unclear (Pi•ko•-Mirkowa 1979). Recently the presence of this species in Poland has been confirmed and this paper presents a review and description of Polish localities. Fifteen new localities of D. remota were found in the Beskidy Mountains (S Poland), and two contemporary and six historical sites confirmed. Ecological requirements in Poland are described. Determination of the Polish specimens of D. remota was based on comparison with descriptions and iconography of this species and in consultation with specialists in Dryopteris. A map of the distribution of D. remota within Poland is provided.