sábado, 26 de fevereiro de 2011
Arborizaçao urbana das cidades britânicas está ameaçada por doenças
What is killing Britain's street trees?
Trees in Britain are struggling to come to life this winter following outbreak of disease, gritting of roads and over-zealous health and safety.
Climate change and the increasing movement of horticultural plants around the country has increased the risk of disease. Chestnuts are suffering from bleeding canker and a leaf miner moth and many have had to be killed on Britain's streets. Oaks, that are more often found in parks, are being killed by acute oak decline. And Japanese larch, that is a popular ornamental tree, is dying from sudden oak death.
Heaving gritting ove the roads over the last two winters has affected trees. Rock salt - or sodium chloride - is the most popular and cheapest treatment used by gritters, but when the ice or snow melts the toxic runoff can easily seep into soil - starving trees of moisture. Salt will also subject the roots to 'toxic attack' - causing them to slowly die off.
Health and Safety
Councils are increasingly nervous about falling branches and hay fever. A line of 200-year-old trees were felled in Bradford after one fell down in a storm and apple trees were chopped down in North Yorkshire for fear fruit would fall on people's heads.
Fonte: The Teleghaph