Ancient Woodland Indicators

On Wednesday I attended another CIEEM regional event, which was looking at woodlands and particularly Ancient Woodland Indicators (AWI).

This was held at Hackfall wood just north of Grewelthorpe in North Yorkshire - an area much visited in the past. I have not been up there for several years, and was reminded what a beautiful part of the world it is.

The site is now managed by the Woodland Trust, and has a new car park, footpaths and interpretation board. There are many and varied plants, and stunning views, as well as a range of follies to explore.  This is definitely worth another visit, when I have more time to explore and photograph at my own pace.

We spent a couple of hours in the afternoon taking a slow wander through the steep, riverside woodland - much of it on well worn paths, but occasionally venturing off piste to look at particular plant species.  We considered plants that are good and bad indicators of ancient woodland, and that these can vary from county to county. We managed to locate the distinctive yet easy to miss Herb Paris, and the unusually looking Toothworth that is a parasitic plant found around the base of hazel trees.

We also discussed survey techniques, and the merits of carrying out a range of transect and quadrat surveys to best describe the woodland. We saw how the nature of the woodland can vary even over a very small area, with noticeable changes in vegetation. Some plants have clear preferences for the wetter areas alongside streams for example, or the dark northern areas that receive little light.  Point locations can also be taken to highlight particularly noteworthy plants.

It is also important to consider the factors that make woodland diverse and valuable, such as fallen wood, marshy areas, streams, etc. After a rather strenuous climb back up to the car park, we reconvened at the Crown Inn to socialise and have a bit to eat.