Posted: 27/02/2015 at 18:13
Most people interested in ecology have heard of Sir Richard Southwood and his 1961 work on British Trees and Shrubs and their associated insects. I remember memorising the list as a student. But not everyone knows his 1961 work was updated, twice, first in '84 to include mites and lichens and again in 2006. The 2006 update is so much more useful. It always frustrated me that the '61 work was merely an indication of diversity without really describing it's benefit overall to other wildlife in real terms, i.e., insectivores and, subsequently to predators that feed on them etc. Take as, my favourite example, the native Field Maple and the introduced Sycamore. The associated insects for the Field Maple is 26 while the Sycamore just 15, almost half. Yet anyone that knows the Sycamore will know it's covered in juicy greenfly and mites etc.. Consequently Sycamores have had a really bad press since they're quite invasive. A quick look at the updated data, however, shows that the Biomass of the Sycamore's foliage invertebrates is given a 5 star rating as opposed to just 1 star for the native Field Maple. Now, I'm sure nobody is suggesting plant loads of Sycamores but it's reassuring to know that they aren't so bad afterall, and when you take into account Mychorizal Fungi, Wood decay fungi, Wood decay inverts, Leaf litter benefit, Blossom for pollen and nectar, Fruits, Seeds and Epiphite community then it comes in an incredible third place after Native Oaks and the Birches. Very impressive indeed for a non-native!
Well, you can take a look at the data and the original text. I have entered it into various tables it can be sorted according to the different, above, criteria.
I have to admit I've not had a chance to have it proof read so forgive me if there's any mistakes, but you can check it yourself against the original text. By the way, I suggest you have a look at the text before making any decisions based on the data anyway. (The text is also linked on the above page.)