Gooseberry sawfly larvae

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The tell tale signs of gooseberry sawfly larvae at work – all but the toughest ribs of the leaves completely eaten away.
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The culprit – a gooseberry sawfly larva
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And another (usually there would be more than two on a bush, but I had spotted the siblings of these two a few days ago and nipped out that part of the bush while the larvae were still tiny – these are the lucky two that got away)

I have seen sawflies on commercial fruit plots strip dozens of bushes completely bare, seemingly overnight. Some people try to control them with sprays; others just accept them. Some say that because the sawflies usually affect the bushes quite late in the season they don’t affect the fruit yield. I tend to nip them off if I spot them, and leave them for the birds to eat (and wonder why the birds aren’t eating them anyway…).

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Renovating a daisy bush (Olearia macrodonta)

Last winter’s and this spring’s storms and hard frosts left one of my daisy bushes (Olearia macrodonta) looking a little the worse for wear. It was also getting a bit leggy. So, back at the end of March I gave it a bit of a chop.

I couldn’t find much information on just how hard to cut it back – my books all said “little pruning is necessary” and “remove dead or diseased branches in spring”. Not so helpful, really.

The branches I wanted to take out were about five or six years old and just over an inch in diameter. Apart from the leaves at their tips they were bare all the way down their stems.

I took about four feet off; leaving about two feet of bare branch. And then I waited. And waited. By the middle of May I was becoming a bit worried that the branches wouldn’t revive. But scraping their bark showed they were still green and vital. So, I waited some more.

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Olearia macrodonta buds bursting

Happily, in the last couple of days the branches have started to throw buds up all along their length, right up to the cut ends.

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Daisy bush buds springing up along a cut branch (nb the glossy green leaves are of a Choisya growing behind the Olearia – the Olearia buds have the reddish leaf stalks)

I have heard that you can cut a daisy bush right down to the ground and it will resprout. But I’ve also heard that they might just give up and die. So, I prefer a more gradual approach to rejuvenation, and hope that this bush will be back to its full flowering beauty next summer.

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Flowers on a neighbouring, unpruned, Olearia macrodonta

Carobs and cork oaks after a withering winter

In October last year, Storm Ophelia arrived in the UK. That marked the beginning of what has turned out to be a pretty tiresome winter for the cork oaks and carob trees.

Storm Ophelia was a complete novelty to me. Usually when hurricanes arrive in the UK they are cold and wet. Ophelia was hot and dry. Although it was October, the temperature rose above 20C with winds consistently above 50mph and gusting to 90mph and more.

The results of this on the cork oaks especially were severe scorch of the mature leaves and complete desiccation of all the growing tips: and there are a lot of growing tips on the cork oaks in autumn.

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This is the main growing tip (leader) of the oldest cork oak. The main damage was done by Storm Ophelia, compounded by the very cold weather and hard frosts we had throughout February 2018.
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Cork oak leaves severely Storm Ophelia

The story was similar with the carob trees, but they have suffered even more from the poor weather that has beleaguered us this winter.

Like the cork oaks, they had a lot of young growth at the start of the autumn (typical of many Mediterranean species – they have a spurt of growth in spring, sit out the summer, and then have another growth spurt in the autumn). As with the oaks, Storm Ophelia sucked the life from those fresh young shoots. But the carobs are still in pots and were, therefore, less able to stand the vagaries of the weather. It has been too cold, too dark and too wet for too long for them and they aren’t looking great.

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Carob leaflet scorched after Storm Ophelia
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The main growing tip of a young carob tree scorched by the storm and now infected with mo(u)ld (but notice the lovely new bud forming at the bottom of the picture)
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Mo(u)ld “flowering” on one of the dying carob stalks

However, although this sounds very negative, I am hopeful that most of the young trees are going to get through this. The cork oaks have sturdy root systems and, I hope, enough reserves to pull back from.

The carob trees, although they look pretty dire, do have plenty of potential new growth points and even a few new shoots springing up from low down on their stems.

Incidentally, I do leave the “dead, dying and mo(u)ldy” bits on the carob trees. I have found that cutting them out just spreads the dieback further and faster. By leaving them, provided the plant is strong enough, it should be able to compartmentalise the decay and stop it spreading too far: which,if my memory serves me well, is pretty much what they taught us at college – CODIT – compartmentalisation of decay in trees/timber.

Tufted caterpillars

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Vapourer moth (Orygia antiqua) caterpillar on strawberry tree (Arbutus unedo)

I spotted this stunning caterpillar munching away on the strawberry tree that I planted last winter. When I looked it up I found that it is, I think, a vapourer moth caterpillar. Everything I read suggested that these caterpillars feed on deciduous trees, especially fruit trees. So I thought that it must have fallen down from one of the neighbouring trees. But looking more closely, I noticed three of its shed skins on the undersides of the strawberry tree’s leaves. So it would seem it has completed its caterpillar life stage here, quite happily eating the strawberry tree’s evergreen leaves. In total, this one caterpillar has eaten less than one leaf. I read that they are “no longer a significant pest in orchards because of the use of insecticides”…

I also spotted another tufted caterpillar on a snowy mespilus shrub (Amelanchier lamarckii). It’s not as impressive as the vapourer, but still quite striking. It too is a moth caterpillar, this time of the grey dagger (Acronicta psi).

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Caterpillar of grey dagger moth on snow mespilus

It always puzzles me that many people say they like butterflies; but they think moths are somehow less nice; and caterpillars are purely pests.

 

 

Privet leaf miner damage

Following the winter’s damage, I’ve been keeping an eye out to make sure the privet bushes recover OK. By and large, they are doing just that. However, I’d say some are a little weaker than would be usual, but it’s hard to tell. One thing I have noticed though is a surge in the amount of leaf miner damage.

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Damage on a privet leaf caused by leaf mining caterpillars (Gracillaria syringella)

The damage first shows as brownish marks on the leaves. They quickly expand to become a large brown blister. By this stage the blisters are easy to pull open and inside there are little tribes of larvae living a sheltered life between the upper and lower leaf surfaces.

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Inside the blister there are little tiny caterpillars – they’re quite hard to see and to photograph because as soon as their blister is burst they try and wriggle away to hide

These larvae will grow up to become tiny little micro moths – Gracillaria syringella. As the name suggests, they also mine lilac (Syringa) leaves and are known as lilac leaf miners as well as privet leaf miners. There are plenty of them on the lilac bushes this year too.

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Leaf miner damage on a lilac leaf
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…and here are the larvae inside the lilac leaf’s blister

 

Metamorphosis

At the end of last summer, the caterpillars of the large white butterfly (Pieris brassicae or cabbage white) left their food plants in the garden and went marching en masse. Most of them marched right out of the garden: they climbed sheds, walls and fences, seemingly knowing where they were heading. But one of them choose to stop and pupate in a stone outhouse where I keep ladders and various bits and bobs.

Throughout the winter, I’ve been careful not to knock the chrysalis off. And for the last few weeks I’ve been watching for “it” to happen: for the butterfly to emerge. Today was the day.

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This was the pupa on 12th May: it was starting to change colour and plump up
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This was first thing this morning (19th May). The wings are clearly visible, squished up against the side and the whole thing looked fit to burst – which it was!
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Here it is, freshly emerged – the empty case that the butterfly crawled out from is towards the bottom, just left of centre

I know it is “just” a cabbage white, and something of a pest, but I am awestruck by the complexities of nature and very happy that this one survived the winter 🙂

 

Winter damage: privet

The first two weeks of March were very mild here, spurring some plants on to make early growth. Fresh growth on privet (Ligustrum ovalifolium) was particularly noticeable. But then, the third week of March brought a week of frosts and freezing winds.

It was at the beginning of April that I started to notice wilt and blackening on privets. My first thought was that it must be cold damage.

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Wilt and discolouration of new growth on privet, April 2017

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But then I wondered whether it might be something worse. It seemed the more I looked, the more I found wilting shoots of privet. I found them on all ages of bushes – from last year’s cuttings to gnarly old hedge plants – and on plain and variegated plants. I found them at the bottom of bushes and at the top; on plants that were pot grown, and plants in the ground. You can see in the pictures that one shoot would be wilted whilst its neighbour seems to continue in rude health.

In the end, it is the fact that the problem is so widely spread, especially that it is in pot grown cuttings as well as plants in the ground, that makes me think it must be cold damage.

For now, until I am sure that winter has finally gone away, I am leaving the dead shoots on the plants and will trim them over when better weather finally arrives.