Bowthorpe Marshes – Scrub and Pathway Maintenance

Friday 20th May 2016

It’s a sure sign that the holiday season is upon us when the number of volunteers reporting for duty is sorely depleted. This was the case today but as it turned out it was no bad thing as the three of us plus Matt managed to finish all the planned work early.

Today we were on ‘Bowthorpe Marshes’ (Location D on the ‘Where we work’ page on our web site) to cut back blackthorn bushes and also to replace some rotten decking boards on footbridges. Blackthorn is a very invasive plant species and if left unchecked it will totally dominate all other vegetation. This can be seen at other sites that Matt manages, most noticeably on Swardeston Common. There, large areas of the common have been completely taken over by blackthorn, which creates a dense, impenetrable, and very prickly tangle of branches. Very good for some species of birds but very bad for other plant life. They spread rapidly via suckers which can be 15 – 20 cms apart and in a year or two can grow to 60 – 70 cms high. Once the plant has become established it will take a lot of effort to clear a small area of blackthorn and burn the branches, so keeping their growth in check will save a lot more work in the future.

Examples of male and female Banded Demoiselles (Calopteryx splendens) and Orange-tip butterflies (Anthocharis cardamines).

On Bowthorpe Marshes it is important to keep the growth of blackthorn in check, so today we were cutting back a patch of ground that we last cut down in the autumn of 2014. This will allow the grass and wild flowers to flourish which in turn will attract more birds and insects. To demonstrate this point, today we saw on the marsh ‘banded demoiselles’ and ‘orange tip butterflies’ (the latter, which feeds on the ‘Cuckooflower’, is a plant that is returning to the marsh as a result of the marsh management work done by Norwich Fringe Project).  Even so it took two people with brush cutters over two hours to cut down the new growth on an area about the size of a tennis court.

Blackthorn clearing and grass cutting with a very smoky fire.

We then set about disposing of the bushes by burning them (burning is not something that is normally done at this time of year but with a large pile of blackthorn to dispose of burning was really the only option), which is when the situation got ‘’interesting’’. Blackthorn normally burns easily but these young shoots, full of spring sap created large amounts of dense white/grey smoke which completely enveloped the whole marsh area. Fearful that we were going to see blue flashing lights atop of large red trucks descending on us, Matt thought it would be a good plan to ring Norfolk Fire & Rescue HQ to explain to them that if they got a call to say that the marsh was on fire, not to worry as all was under control. In the autumn and winter periods we are quite used to creating smoke when we burn trees that have been cut down but today this prodigious amount of smoke was quite exceptional. There was a gentle breeze blowing across the marsh which was just enough to move the smoke towards the distant houses but not enough to disperse the smoke.  It seemed as if we had created our own London smog of the 1950’s.

Between the smoke signals, repair of the boardwalk was in progress.
Between the smoke signals, repair of the boardwalk was in progress.

Whether the Fire Service received any calls about our smoke or not, they didn’t say when we rang again to say we had finished our pyrotechnics for the day. When all was burned, we duly dampened the fire down with water from a nearby pond.

The rotten decking boards had been replaced whilst the brush cutters were at work, so for the second week in a row we were able to finish our allotted tasks soon after lunch. Just as well it is close to holiday time, because if the usual number of volunteers had turned up, we would have been homeward bound before lunch.

Written by Alan Rae, Norwich Fringe Project Volunteer.