Saturday 7 September 2013

Native and Non-Native

It's always a bit of an argument just how far you go in advocating species fundamentalism in relation to native and non native trees and wildlife generally. The trusty rule of thumb that what looks right may well be right works for me but sadly might not be the same for you. Still I think it should be part of the picture.

More likely to be used in arguments are tables of species diversity and biomass. Like all statistics they need regular updating and rigorous appraisal. The table of Value of Different Tree Species for Invertebrates and Lichens is useful as a guide though it might need some more work to be comprehensive. It shows the introduced Horse Chestnut as having only four insect species associated with it.



This one is very much a lone specimen at the Lenny Hill cross-routes. Some promising conkers on it, and I've always suspected its origin was a conker falling out of a small boy's pocket. I've not seen any others within half a mile.

Oak and Birch are, along with Willow, at the top of the table for this biodiversity measure. Willow is present but doesn't dominate on Blacka as yet while Oak and Birch are plentiful. Native Oak is quoted as having 423 species plus 324 associated lichen species. For Birch it's 334 and 126.



The introduced Oak here, which I take to be Turkey Oak, does not figure separately in the table. Interestingly its early foliage this year was devastated by certain insect activity and those leaves can be seen on this photo. As can be seen it recovered vigorously later on leaving the ravaged early leaves 

Generally I stick to the view that we should do all we can to encourage the natural renewal and the plantings of native trees. They have a vital role in ecological restoration and, anyway, I just like the look of them in the wilder setting. The other more exotic stuff serves a purpose in the fantasy lands of landscape gardening found in stately home parkland that I occasionally enjoy. But wild land has its own enchantment. In all the talk of heritage in our landscape what can have more heritage value than the plants trees and other wildlife that is native to our island?

No comments: