Now that the third warmest November on record has come to an end, winter has swept down from the Arctic and the first frosts of the season have arrived. Herne Hill’s streets are looking a little forlorn after a vivid autumn, but there are still patches of very late colour to enjoy. And of course these dormant months until the end of March are the perfect time to plant bare-rooted trees.
Planting campaign kicks off
It won’t have escaped your notice that preparations for the winter/spring planting season are well underway. Southwark’s contractors were out and about during November and 46 brand new tree pits have appeared, all neatly edged, filled with soil and ready for their saplings. We’re currently projecting 76 new arrivals are coming along, including trees on grassy areas that don’t need pits, although that total will change as the weeks go by.
We’ve posted a detailed and up-to-date planting schedule on the website but here’s a street-by-street summary (as of December 7) of what’s expected where:
Beckwith Road: 4 trees
Burbage Road: 1 tree
Carver Road: 3 trees
Casino Avenue: 16 trees
Danecroft Road: 6 trees
Delawyk Crescent: 1 tree
Elfindale Road: 2 trees
Elmwood Road: 3 trees
Frankfurt Road: 3 trees
Half Moon Lane: 3 trees
Herne Hill: 2 trees
Hollingbourne Road: 3 trees
Holmdene Avenue: 1 tree
Nairne Grove: 5 trees
Red Post Hill: 7 trees
Ruskin Walk: 4 trees
Sunray Avenue: 4 trees
Warmington Road: 3 trees
Wyneham Road: 5 trees
Some of these numbers are in a bit of flux. On Casino Avenue, for example, five more pits were dug last month but then filled in and tarred over within days. We’re trying to find out from the council what was behind that decision. On a positive note, though, Wyneham Road has got one more tree pit than we were expecting, outside no. 14.
There are a few other locations where we’re still not sure about the prospects, among them a handful of places where trees were lost earlier this year. But on the whole it’s very heartening to see so many trees on the way, especially on long stretches of pavement on Nairne Grove, Warmington Road, Wyneham and Casino that have stayed virtually bare up to now.
Don’t forget we’ve applied for more funds from the council to plant bigger, shadier trees this time next year. It would be great if our street leaders could start thinking about where these might go. We’re looking for roads with one or more big gaps to fill, reasonably wide pavements and houses that are set back a little to give the trees space to grow. Do let us know your thoughts. We’ll come up with some suitable species in the meantime.
The last of autumn
This year’s autumn came late, delayed by heatwave, the drought and the subsequent heavy rainstorms that spurred unexpected late summer growth. Even now, in December, some trees are clinging to their leaves well after others have shed them all.
A few of the sweet gums (Liquidambar styraciflua) that we featured in October for their autumn colour are still making a splash. One outside the Dulwich Mead flats at 48-50 Half Moon Lane, just opposite Ruskin Walk, is still very prettily decorated in green, yellow, orange, red and very dark burgundy. You can’t miss it if you’re scanning the horizon from the bus stop to see whether your 37 to Brixton is on its way.
Our very few whitebeams (Sorbus aria) also put on a nice show this year. The birds had taken all the bright red berries well before the end of November, but the big leaves on this tree at 80 Holmdene were still hanging on.
There’s another whitebeam outside 66 Ruskin, not as big as the Holmdene tree and rather cramped under a very vigorous and shapely Pauls’ Scarlet hawthorn (Crataegus laevigata ʽPaul's Scarlet’) in the front garden there. The only other street whitebeam that we’re familiar with is a little two-year-old outside Bessemer Grange school, next to 17 Nairne Grove.
It’s a shame they’re not more plentiful. They’re one of the few British natives to thrive on our streets, with cheerful white blossom in May, glossy green leaves with a strikingly pale, slightly furry underside and bunches of berries in late summer and autumn.
Callery pears: a thorny problem in the USA
By contrast, Herne Hill has dozens of Callery pears (Pyrus calleryana) and they’ve also been reluctant to drop their leaves. They seem to have been more colourful than usual in the last month or two, like this rather lovely specimen at the top of Hollingbourne, by the entrance to the Herne Hill School kindergarten on the corner.
It’s a Chanticleer cultivar (Pyrus calleryana Chanticleer), the most numerous variety in the area. We also have four Redspires (Pyrus calleryana Redspire), which in some ways are more interesting - two on Stradella, at no. 4 and no. 6, and a pair on Wyneham Road, one at no. 9 and one at the Beckwith end of the street, outside 39b Beckwith. Their autumn colours are usually better than the Chanticleers, and in the summer the foliage on their thick, upswept limbs is darker, glossier and denser.
The Callery pear was brought to Europe from China in the 19th century by the Italian-born botanist Joseph-Marie Callery and introduced to the United States in the early 1900s. There it was valued as a hardy rootstock for the common edible pear (Pyrus communis). In other words, a cutting from an edible pear was grafted on to the roots and part of the stem of a Pyrus calleryana to produce a hardier and more disease-resistant fruiting pear.
It wasn’t until the 1950s that ornamental varieties like Bradford started to be developed, also grafted on to rootstock from the parent. Widely planted as landscape trees from the 1960s onwards, within 30 years cultivated pears were found to have spread to gardens, roadsides, empty plots of land, fields and forests, displacing native trees. They’re now considered an invasive species all over the eastern USA and are being banned from sale in South Carolina, Pennsylvania and Ohio.
The problem arose because although individual grafted cultivars of Callery pears can’t reproduce, they can cross-pollinate with other varieties. So while one Chanticleer can’t pollinate another, it can cross with a Bradford, say. Birds eat the fruit of the new offspring and drop the seeds across the countryside, where they grow aggressively. Nothing can grow under a dense thicket of these ‘wild’ Callery pears and wildlife can’t get past their long, vicious thorns.
These thorns are a throwback to the original well-armoured Callery pears from China, which provided the rootstock for the grafted varieties. Thorns don’t grow on the branches of our ornamental pears, but you will see them on the suckers that often spring from the base of the Chanticleers. That’s why we prune back these vigorous shoots every winter.
What are trees worth?
We all value our trees highly: for their beauty, their contribution to our well-being and the environmental benefits they bring. But a new report from Forest Research, the research agency of the Forestry Commission, has for the first time put a monetary value on what they call non-woodland trees: single trees in urban and rural settings, groups of trees covering less than 0.1 hectares and small woods. Together they cover about three-quarters of a million hectares in the UK, including streets, gardens, parks and fields.
The study says the ‘ecosystem services’ these trees provide are worth between £1.4 billion and £3.8 billion a year to the country. Their most valuable service is carbon sequestration - the capture and storage of carbon dioxide from the atmosphere. The next biggest is the removal of air pollution, but they also prevent rainwater run-off, reduce noise, mitigate flooding and regulate the temperature.
Three years ago, a report by the Treeconomics consultancy made similar estimates for the 82,000 trees managed by Southwark Council in streets, parks, housing estates, school grounds and woodland. It found that they
removed over 19 tonnes of air-borne pollutants every year, saving £1.3 million in health and other social costs
stored over 50,000 tonnes of carbon above and below ground, with a value of £12.5 million
and diverted over 31,000 cubic metres of stormwater run-off from the sewers, avoiding £47,000 in treatment charges.
Kommentare