Ashdown Forest is undeniably special (it represents 3% of the remaining heathland in the UK) but it is also quite unusual. For a start, in terms of ‘lowland’ heathland, it’s actually quite high up. There is an arbitrary cut-off point in ecology between lowland heath and moorland, the huge expanses of upland heather managed for grouse shooting. The cut-off is 200m above sea level; the highest point on the Forest is 229m. This means that, compared to the ‘classic’ lowland heaths of places like Purbeck and the Lizard, Ashdown Forest is quite cool and experiences relatively high rainfall.
The other unusual feature is the soils. Heaths are characterised by generally free-draining, acidic, sandy soils. The Forest soils are indeed acidic and sandy, but the particle size of the Ashdown sands is very small, closer to silt. This means that drainage is often poor and, combined with the heavy rainfall, much of the Forest is very wet.
Which is a good thing, as long as you have wellies. Wet flushes, ghyll woodland, valley mires and boggy pools all provide additional habitats for a host species that wouldn’t otherwise be so abundant on the Forest. One group that does particularly well is the Odonata, or dragonflies. I have blogged before about our Small red damselfly, but there are plenty more species to look out for on the Forest.
Perhaps the most impressive – if relatively widespread – species is the Emperor dragonfly, the largest (though not the longest) species found in the UK.
Prize for the longest species goes to the female Golden-ringed dragonfly, a scarce species found across the High Weald but reaching its greatest abundance on the Forest.
A real Forest speciality is the Keeled skimmer, found nowhere else in the county. The male is an attractive chalky blue, similar to the much commoner Broad-bodied chaser.
Similar again is the Four-spotted chaser, though both the male and female are brown. The distinguishing feature is the presence of dark spots on all four wings.
The damselflies, smaller cousins of the dragons, are well represented on the Forest too. I have already blogged about the Large red and rarer Small red; the blues are abundant everywhere, but perhaps my favourite of all is the exquisite Emerald damselfly. If Faberge had made an insect, it would look like this.