UK Nature Blog

An end to Japanese knotweed?

It's rare that plants make headline news, but that's exactly what Japanese knotweed has managed today here in the UK.

There are very few gardeners that have not had their own personal battle with Japanese knotweed and bearing in mind that it can grow up to a meter a month that's no surprise. Its strength means that it can break through concrete and tarmac though and as a result it is estimated that £150 million a year that goes into repairing the damage that it does to roads, pavements and buildings. A large cost like this has meant that people are keen to find a solution to the problem, especially since it manages to grow in its native Japan without this kind of problem.

Japanese knotweed was originally brought to the UK by the Victorians as an ornamental plant, but the problem seems to be that it has no natural predators here. Researchers at CABI have been looking into knotweed's predators back in Japan (both insect and fungi) and have been testing them on over 90 UK plant types to try to find one that would have no harmful effects on other plants. 

It has today been announced by Defra that the go-ahead has been given for an insect called a psyllid (aphalara itadori) to be released in England to fight knotweed. No bigger than a grain of sand, the psyllid lay eggs on the weed and the hatched larvae suck out the sap to kill it. 

The release of the psyllid is the first time that biocontrol has been used in Europe to fight a weed. Initially the insects will be released at a couple of isolated sites where there is a known knotweed problem. Careful monitoring will take place to ensure that the insects only impact on the knotweed and countermeasures are in place in case it is found that this is not the case.

Fussy eaters

This blog post over at the RSPB shows examples of berry-laden bushes that have remained untouched by the wildlife over the winter. Do they just not like them? I don't know, but I too have noticed whole trees smothered in red berries and was surprised that they hadn't been scoffed. Having watched the Pyracantha being systematically stripped by blackbirds and with the bleak winter we've had I'm particularly surprised.

M4 in reverse

Coming back up the M4 from the West, I again kept an eye out for wildlife. Same as on the way out there was only a single Red kite to be seen, though plenty of Buzzards. Most unusual though was what looked like a pair of Red-legged partridge happily pecking along the hard shoulder oblivious to the speeding traffic. They looked fairly exotic, but stubby and small compared to a female pheasant so I'm fairly sure this is what it must have been. I don't believe I've seen them in the flesh before, so I had to guess at what they might be and identify them after the fact from memory.

M4

Travelling along the M4 motorway the other day reminded me what a great journey it is for spotting raptors (the birds not the dinosaurs). I saw lots of Buzzards, sometimes circling in groups of three or four. Unusually I only saw one Red kite, whereas they ate usually liberally sprinkled along the way. A few Kestrels hovering too.

Frozen pond oxygen supply

This picture is a good example of how beneath the ice of a pond, there may in fact be plenty of oxygen for wildlife, as that given off by the aquatic plants is trapped.

Frogspawn

If the buzz on Twitter is to be believed, the last couple of sunny days have got frogs in the mood and frogspawn is appearing in ponds across the UK. The link is a live search for "frogspawn" so will pick up whatever's most recently been tweeted.

Mating Kingfishers

For most people a glimpse of one Kingfisher is quite special, but two, together, very together in fact, is extremely unusual. So the Telegraph's report and photograph of Kingfishers mating is quite something.

I saw a Kingfisher just yesterday as it happens, which reassures me that the harsh winter hasn't killed them all off. Apparently (and I've now read this in several places, including the article above) very harsh winters past have decimated populations by 90%, and it then takes a long while for them to recover.

Muntjac deer

I've seen Muntjac deer before, but usually just the rear end rapidly disappearing into the undergrowth. They are quite dissimilar to other British deer, being small and stocky with tiny straight horns and little tusks - almost like a cross between a wild boar and what you might classically think of as a deer shape. They are also very wary and prefer to skulk through overgrown thickets. That's why I was quite surprised to see this one ambling slowly over a footbridge then casually grazing on the grass beside a path on the other side.

Usually I don't have time to pull out a camera before they're gone, so this was quite the golden opportunity. Unfortunately I only had a small compact camera with me, which has struggled to get a good image, but it's still the best I've ever managed.

Growth spurt

The weather has warmed up a bit (at least in the South) to as high as 10c during the day. Positively balmy! This, perhaps combined with all the rain, seems to have triggered a growth spurt, with lawns now needing mowing and bulbs thrusting up everywhere you look, even in beds that I could have sworn I dug over very thoroughly just 6 months ago, without finding any bulbs! Each morning on my walk to work I see gardens full of fresh green shoots so I'm looking forward to a riot of colour over the coming weeks and months.

Gull camouflage

An arty shot from the archives today. This is a gull blending into the rocks of the Dorset coast, with only a bit of post-processing to convert to black and white and improve the contrast.