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.

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

 

Currant blister aphids

The the new leaves have recently unfurled on a redcurrant I bought over the winter. And the leaves have bright red blisters.

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Discoloured blistering on a young redcurrant leaf

These blisters look like a text book image for currant blister aphids. Sure enough, when I looked at the underside of the leaf, there was a big fat aphid with a brood of babies…

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Redcurrant leaf with blistering and aphids

These bugs must have come in as eggs on the plant. According to the RHS, the aphids need to move to hedge woundwort (Stachys sylvatica) plants to complete their life cycle: they’re uncommon plants around here, so this could be the end of the road for these aphids, depending how far they can travel. The damage the aphids are doing looks impressive, but is really of no consequence.

Tassels!

This beautiful little tassel tree (Garrya elliptica) was bought last autumn. It’s only a baby, and possibly it shouldn’t have been left to flower so prolifically. But it looks just beautiful, especially now the sun is shining.

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Tassels (male flowers) on a baby tassel tree (Garrya elliptica), January 2017

The tassel tree, or silk tassel tree, grows to around 4m tall with a similar spread – so it’s more like a big shrub really.

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Through the tassels

Tassel trees are mainly grown for their attractive catkins (tassels) that brighten up the darkest time of winter. Incidentally, the male and female catkins are borne on separate trees: you want a male tree for the best catkin display. These trees are also quite hardy, down to about -10C, but like all plants, they’re more tender when they’re young.

(The blotches you can see on the leaves are most probably fungal and came with the plant from the nursery. It was over dry and overly pot bound, meaning it was stressed and consequently vulnerable to infestations / infections. Hopefully in the coming year with a bit of pruning and good watering and feeding it will grow away from the fungal infection.)