Bentley Wood
Site feature providing more detailed description, photos and other information for the butterfly observer
Photo 1 - View Along The Switchback From The Car Park
Highlights
- Large mixed woodland on Hants/Wilts border
- Nationally recognised for its importance as a butterfly site
- Every woodland species resident in central southern
- Small colony of Marsh Fritillary
- One of the best sites in the country to observe Purple Emperor
Description
Bentley Wood is large mixed woodland on the Hants/Wilts border - and yes, OK, so most of it is in Wiltshire! Its importance as a butterfly site is nationally recognised, and reinforced through its designation as a Site of Special Scientific Interest (SSSI). More than 35 butterfly species are recorded there regularly, including every woodland species resident in central southern
For visitors approaching from Hampshire, use the Tytherley Road entrance. The car park is located about ½ km along a rather bumpy track. For visits during May to see the small fritillaries (Pearl-bordered, Small Pearl-bordered and Marsh Fritillary), go to the Eastern Clearing (arrowed on map) by heading on foot 100 yards back down the track, then under a wooden bar into the clearing (Photo 2). The Pearl-bordered are first on the wing - from around the second week in May, with the Marsh Fritillary and Small Pearl-bordered appearing typically in the third and fourth weeks respectively. Hence in late May all 3 species should be on the wing although the Pearl-bordered will be fading by then. Whilst the Pearl-bordered Fritillaries can be found over a large area of the clearing, and also along some of the open rides in the wood, the Marsh Fritillary and Small-Pearl-bordered favour the eastern end towards the
Photo 2 - The Eastern Clearing - Site For Pearl-bordered Fritillary
If your visit is in July and aimed at Purple Emperor, they are most active during the mornings, so be there early (e.g. 9am). Bright or broken cloud conditions with little wind seem to be best, but the species is unpredictable. The car park is a good place to wait, since the males will occasionally swoop down from a nearby oak and do a circuit or two - sometimes landing briefly on a shiny metallic car or a tyre which has the remnants of dung on it! Visitors occasionally put well ripened fruit on top of the visitor board to attract Purple Emperors – and with some success. Apparently Danish blue vein cheese is good too! I have also found the switchback as far as the first major cross-tracks to be productive, with puddles and animal droppings attracting the butterflies down to feed.
As already indicated, Silver-washed Fritillary can be very common, and there can be an unusually high proportion of the normally rare female aberrant form, called Valezina, where the golden brown background colour is replaced by a greenish bronze.
There are also several small colonies of White-letter Hairstreak around the wood, the best known being close to the Ralph Whitlock memorial. Turn right at the first cross-tracks on the switchback, continue through a slight depression and across another set of cross-tracks until the main track is about to turn right. There are two isolated Wych Elms facing you on this bend (map) which are home to a colony of White-letter Hairstreak. The memorial is a few yards down the minor track to the left where there are more elms (some diseased) and elm suckers, which are also worth a look for White-letter activity.
If your visit is not particularly aimed at a particular species, but simply because Bentley Wood is such an excellent woodland butterfly site, then just enjoy your visit – it is a special place. The different areas of the wood have their own unique characteristics, which reflect in their butterfly populations, and exploration of some of its more remote areas will rarely disappoint.