110 likes | 126 Views
This report highlights areas for improvement in the Amey species list for tree planting in Sheffield. It suggests selecting species with higher wildlife value, considering innovative and disease-resistant varieties, accommodating local conditions, and addressing care issues after planting.
E N D
Views on the Amey list of tree species used when planting new saplings Sheffield Tree Action Groups (STAG) September 2019
Positives • The (expanded) list Darren Butt showed us in September 2018 is a long list of 78 species • It includes many species and genus unused (or barely used) in the 36,000 trees Amey inherited in 2012 • If used in full, it really would increase the variety and disease/pest resilience of the tree stock in Sheffield
Areas for improvement – Many species are not useful to wildlife • Many of the Cherry species used are of varieties which have limited nectar value to insects such as bees • Others also of really low value to wildlife (egGinko) • Canopy size small (either fastigiate or small cultivars), again limiting the wildlife value
Areas for improvement – The list could be more forward thinking and innovative • The elm species used are not ideal. • Whilst DED resistant, they are Asian cultivars. • There are much better DED resistant varieties now available • eg “Fiorente”, “Rebona” and “Wingham” – helping to promote varieties that are close to native Field Elms • The Sorbus varieties used could include some of the very rare native varieties • eg Wild Service, and Wilmott’s Whitebeam – • These would help to increase the population of threatened native trees which also have wildlife value
Areas for improvement – Extreme focus on low maintenance varieties • Fastigiate trees are clearly most appropriate in some circumstances – for example on narrow terraced streets • But canopy is king – in terms of the various benefits. • Similarly, many of the species are slow growing, or small at full size • Need to only use small and/or fastigiate trees where absolutely necessary. Full size trees in all other circumstances
Areas for improvement – Does it really take into account the latest thinking on likely tree diseases and pests soon to enter the UK? • DEFRA have a list on their website of the likely next threats – the known knowns and known unknowns • Does the Amey species list fully take this into account?
Areas for improvement – Incorrect species for location • Are local conditions always thought about? • Wind resistant trees in windy spots? • Drought resistant trees in areas baked by sunshine • Trees that don’t mind waterlogged conditions in areas prone to flooding, or in heavy clay • Needs to take account of "special" areas - these include conservation areas, memorial trees, avenues, and the fact that 1/3 of Sheffield District is in the Peak National Park where specific rules may apply to what you can plant. • Some species selection has been odd: • Black Pine on corner of narrow pavement • London Plane in an avenue of 96 Lime trees • Lime tree in a tree pit of a Lime that died from fungus
Areas for improvement – Earlier flowering species could be used • Early emerging insects struggle to find nectar • Could more early flowering trees be used? • eg add Magnolia, and increase the use of both Birch and the right sort ofearly flowering Cherry
Areas for improvement – Undersize trees being planted • Even ignoring the species list, the specimens being sourced do not always meet the contract requirements in terms of girth and height for new plantings • Leaves them vulnerable and gets them off to a bad start • Not just odd examples – large numbers
Areas for improvement – Care after planting • Care after planting leaves a lot to be desired • Watering regime is part of the contract and was not adhered to • Weeds in tree pit also • Is the use of woodchip as mulch appropriate? – takes nitrogen from the soil when it decomposes, • “Liberal” use of weedkiller to kill weeds in pavement cracks – and into tree pits…. • Lots of examples of strimmer damage to new saplings – completely careless
Summary • The Amey species list is a start, but it needs some work • Most important is not the list itself, but picking trees from the list appropriate to each site, ensuring: • Canopy size is maximised – limiting the use of fastigiate and small species • “The biggest possible tree for the space available” • Maximising wildlife value • Ensuring specimens used in new planting meet the contract specification (height and girth) • Supporting the trees carefully in their first two years