Small Nettle Re-visited

Back in July 2009 I wrote about some new plant finds - one of which was Small Nettle (Urtica urens). In that blog entry I wrote:

"This is a smaller, more delicate, annual relative of the Common ‘Stinging’ Nettle (it also stings, by the way!). It is generally considered to be an ‘archeophyte’ – that is a plant introduced into this country, from elsewhere in the world (in this case continental Europe), before the wholly arbitrary date of 1500 AD. Like most archeophytes the seed probably arrived as a contaminant of
the crop seeds which were traded between European countries for millennia."

Since then I have found a few more examples - but it's still quite uncommon round here. Perhaps the most unusual site that I found for it was beside a bus stop opposite Stretford Mall!

As I mentioned in my last posting here, over the Christmas holiday period I stayed with my brother in his new house in North Norfolk (not far from Sandringham - now there's posh!). The countryside in that part of the world is sublime and I spent many happy hours wandering the local heaths, fields and lanes and getting pleasantly lost.

At one point I was ambling along a field boundary, trying to suppress the mild panic arising from the fact that I was fairly thoroughly lost by that point (obviously I managed to find my way back eventually - other-wise I wouldn't be writing this!). I suddenly realised that to my left was a grassy verge full of Common Nettle (U. dioica) and to my right a fallow, ploughed field full of Small Nettle. In spite of the fact that some members of these two populations were literally only inches apart there was no overlap. It just goes to show how precise that habitat requirements of some plants are and why, in South Manchester, Small Nettle is now confined to small areas of disturbed ground such as allotments and 'scuffed up' bits of ground beside bus stops!

Dave Bishop, January 2012

Hawthorn in Flower in January

I thought I'd seen it all when I visited my brother in North Norfolk over the Christmas holidays and found a clump of Snowdrops in flower on Boxing Day.; all a bit awkward really as these could not be described as 'the first Snowdrops of 2012', but rather 'the last Snowdrops of 2011'!

Then on the 13th of this month I took a walk along the river bank, from Chorlton to Didsbury, and found eight species of plant in flower. This was a bit unusual - but I told myself that several of these species can be a bit precocious some years.

Then, the day before yesterday (23.01.2012), I found several Hawthorn bushes in flower in a copse, just above the Mersey, near Kingsway. One of the old names for Hawthorn - 'May Blossom' provides a bit of a clue about when Hawthorn should flower.

I could, of course, go on and on and on about 'global warming' (the evidence for which seems pretty convincing to me and will, no doubt, have dire consequences) but I'll spare you and content myself with noting that something very unusual appears to be going on.

Dave Bishop, January 2012

Checking the Nest Boxes on Chorlton Ees and Ivy Green

Last year (2011) FoCM obtained a Council grant which allowed us to put up 20 bird boxes on the Chorlton Ees and Ivy Green Local Nature Reserve (see John Agar’s blog entry for March 2011). We put up 10 boxes on the Ivy Green side of Chorlton Brook and 10 on the Chorlton Ees side.

Last Sunday (15.01.2012) four of us: Dave Bishop, John Agar, John’s son Mark and Mark’s wife Julie set out to see if any of the boxes had been used over the previous nesting season, and to clean out those with old nests in. John brought his extensible, aluminium ladders and Mark his battery powered, electric screw-driver.

On the Ivy Green side of the brook we were dismayed to see that the first two boxes we checked were lying on the ground at the foot of their trees. At first we suspected vandalism but then we noted that the screws holding the boxes to the trees had snapped and the boxes themselves had left indentations in the bark of the trees. We had fixed the boxes to the trees too tightly and the expansion of the tree bark, in the course of the year, had exerted enough pressure to snap the screws! Nevertheless, both of these boxes contained nests. The very first nest had a single tiny egg in it which had obviously failed to hatch (see the rather blurred photograph above).

Of the next seven boxes, one had fallen - but all seven contained nests. As well as the old nest the third fallen box contained cherry stones with small holes gnawed in them. Such holed stones are a sign of mice – probably Wood Mice (Apodemus sylvaticus) – which had taken advantage of the fallen box for their own purposes.

We then moved across the brook to Chorlton Ees. It was a bit depressing to find that four of these boxes had gone missing. One had obviously been stolen because the thief had screwed the screw back into the tree (!) but there was no sign of the other three. We suspect that their screws had snapped and
the fallen boxes had been picked up and taken home to install in someone’s garden (at least, we hope that they’re being used). The remaining six boxes all had nests in them, although it looked as if one of the boxes had been abandoned part way through nest construction because wasps had taken up residence. You can see the remains of the wasps’ nest in the bottom photograph.

The nests we found seemed to be of two general types i.e. constructed almost entirely of moss or fibrous nests on platforms of grass stalks. The fibres used to construct the second type could have been synthetic, because some were green and others red. I suspect, though, that some of the fibres used
could have been dog hairs. Some of the old nests, mainly of the second type, were heavily contaminated with droppings and we suspect that birds had used them for shelter during bad weather.

All of the old nests were removed and discarded. The boxes then were cleaned out and returned to their trees, but this time the screws were not screwed in so tightly to allow for bark expansion.

John Agar’s conclusions on the significance of our findings are given below:

The likeliest species to have bred in our boxes are:

The Great Tit (Parus major) which is the largest and commonest European tit. This species breeds
in late April-June in deciduous woods, hedgerows, parks and increasingly in gardens. They nest in a hole of some kind, usually 3ft to 15ft above the ground, and often in tree stumps or walls, nest boxes and various other artificial sites such as drainpipes flower pots etc.

The Blue Tit (Parus caeruleus) which is the only native bird with blue and yellow plumage. Its breeding habits are similar to those of the Great Tit.

The Coal Tit (Parus ater) which is the smallest European tit being slightly smaller than the Blue Tit. This species breeds in coniferous woodlands but is increasing seen in deciduous woodlands and gardens.

Nests

All three species are remarkably similar in their choice of nesting material. Both sexes carry dry grass and
moss into the hole and lining it with hair, down or wool.

Eggs

All three species lay large clutches of eggs: Great Tits 8 -15, Blue Tits 9-12 and Coal Tits 7-12. There is
a remarkable similarity in the colouring i.e. white with red or reddish brown markings. The egg of the Great Tit is the largest but Coal Tit eggs are larger than those of the Blue Tit - even though it is the smaller bird.

In all three species the eggs are incubated by the female for between 14-18 days, during which time she is fed by the male bird. Hatchlings are fed by both parents and leave the nest after 2-3 weeks,

Remarkably all of our nest boxes had been occupied, although it`s not possible to know if all were successful. However, there was no evidence of dead nestlings in any of the boxes. Ideally the boxes
should have been cleaned out in the autumn when the nesting material would not have been so wet and degraded. I think it reasonable to assume that a good number of nestlings had fledged.

Given that the nesting material of the three species is so similar it is not possible say what number of each were present. It would require observation to be carried out when feeding was in progress. We’ll try to make these observations this year. I would expect that Great/Blue were in the majority with just two three pairs Coal Tits.

Finally, if anyone reading this has ‘rescued ‘any of the four missing boxes from Chorlton Ees, please, please, please make sure that you clean them out before the nesting season starts in a couple of months time!

Dave Bishop and John Agar, January 2012

Trees and Winter Gales

I suppose that if you live around Chorlton Green, or have visited it in the last couple of days, you will have noticed that one of the Lime trees that grow around the edge of the Green has been blown over.

I think that this happened either late on the night of Wednesday 4^th January
or early the next morning.

This tree grew at the north-west corner of the Green and I suspect that that night’s gales were channelled and amplified as they blew down Albemarle Road - making a tree on that particular corner very vulnerable.

In spite of this loss we have escaped very lightly compared to the Royal Botanic Garden in Edinburgh (where the recent gales have been much stronger than those that we have experienced in South Manchester). A report (see ref. below) on the damage to the gardens states that:

“... it will take much longer to replace more than 40 trees blown over in the storms. They include some specimens which were hundreds of years old, and others which were important in the history of the collection.”

The report continues:

“Dr Edwards (a spokesman for the Gardens) [showed the reporter] a huge native oak which had stood more than 15m (45ft) tall, but had been felled by the winds.

"It's a lovely big specimen tree. Or it was. It's now lying sadly on its side," he said.

"But even though this is a big tree the roots don't go down very deep. They actually only go down about two metres (6ft) into the ground. That's often surprising for people."

But the collapse of the tree has allowed experts to see, for the first time ever, what has been going on in the very uppermost branches of these trees.

"This is very exciting for me", Dr Edwards explained.

"These branches are absolutely covered in lichen. And it's not just one species of lichen. There's a whole variety - some of them growing quite luxuriantly."

That matters because lichens are highly sensitive to environmental pollution.

"The fact that there are so many lichens growing here, and they're looking so healthy, is evidence that Edinburgh has got cleaner over the past few decades."

Dr Edwards said the loss of such a tree was "a tragedy" for RBGE.

But, he added: "In some of the more natural woodland areas, this could be seen as nature's way of pruning out diseased and damaged branches and trees.” ”

With this report in mind I went to have a look at the fallen tree on the Green. Sure enough the roots were surprisingly shallow and the upper branches were adorned with lichens (and mosses and, what I assume, is some sort algae). I suspect that the lichen flora on our felled Lime is not as diverse as that on the Edinburgh Oak – but I don’t know enough about lichens to be sure.

Perhaps the saddest thing about this particular loss is that the tree’s twigs bore abundant buds – just waiting to burst forth in the coming spring; this, of course, will never happen now.

During previous winter gales we have lost several trees on Chorlton Ees. The trees there are particularly prone to wind blow after prolonged rains - which soften the ground. I don’t suppose that I need to remind anyone that we’ve had lots and lots of rain recently and the ground is
very soft indeed.

After I’d examined and photographed the fallen tree on the Green, I walked over to the Ees to inspect any damage there. To my great surprise I couldn’t find a single fallen tree (apart, that is, from those blown over in previous years). It could be that the winds were not as strong this winter as they have been in previous years; but another possibility occurred to me:

The trees on Chorlton Ees were planted around 40 years ago. They were planted too close together, have rarely been thinned and, as a result, have tended to grow tall and spindly. In addition, because they are planted trees they have, almost by definition, weakened roots (digging up a tree and re-planting it tends to damage its roots). When these trees reached an optimum
height they became vulnerable to wind blow. But successive winter gales, over the last few years, have now winnowed out the weakest and most vulnerable trees.

From now on fewer will blow down and those that remain may even have stronger
roots (I suspect that the bending and flexing that goes on during gales may
strengthen the roots in such a way that they are more able to withstand the
prevailing winds). I should stress that this is just a hypothesis and don’t be
surprised if we lose more trees if we get more gales this winter or in
subsequent years.

In a spindly plantation, such as that on Chorlton Ees, the loss of
a few trees to gales is no big deal and tends to add to the biodiversity of the
site by letting in more light. In addition, as the fallen trunks rot they form
a habitat for various invertebrates, fungi, mosses and ferns.

Dave Bishop, January, 2012

Reference: 'Worst ever' storm damage at Edinburgh botanic
garden By Huw Williams BBC Scotland reporter, BBC News, Edinburgh, Fife & East
Scotland, 05.01.2012 (http://www.bbc.co.uk/news/uk-scotland-edinburgh-east-fife-16427921)

Get fit in the outdoors - THIS SUNDAY (8th)

Blast awat those January blues and get the blood pumping while helping nature at the same time. Join the Friends of Chorlton Meadows as we help the ground flora of Ivy Green by removing some of the sapling regeneration along a strip of woodland between the nature reserve and the allotments.

Meet: Ivy Green Car Park, Brookburn Road, opposite the Bowling Green pub

Time: 10.30am

If you're late just follow the path to the right hand side of the reserve, if entering from Brookburn Road, and you'll see us.

Young naturalists Wildlife Watch - 7th January

Image: Tom Marshall, CWT

What's the event? Cheshire Wildlife Watch forms the junior branch of Cheshire Wildlife Trust - nationwide, Watch is the leading club for young budding environmentalists. It is run by trained and CRB checked volunteers and consists of environmental activities for children aged 5 - 15.

Activities are varied and could include bug hunts, butterfly spotting, pond dipping, arts and crafts and games for all ages. It’s FREE but we encourage attendees to join Wildlife Watch to get all the benefits of being a junior member, as well as supporting the work of Cheshire Wildlife Trust. Bring wellies and waterproofs in case it’s wet!

When is it? Every 1st Saturday of the month, 2-3.30pm. Next one: 7th January
Where is it? Chorlton Water Park, Visitor Centre, Maitland Road, M21 7JJ

For more details contact: caroline.milson@hotmail.co.uk or checkout the Facebook page 'Chorlton Wildlife Watch'