My acer tree under attack from scale insects
In a rare spell of dry weather the other day I ventured out to drop off some veg peelings into the compost bin. Pausing to have a quick nosey about the garden and see how everything was coping with the deluge of rain we’ve been experiencing I spotted with a sinking feeling an assault on my acer. Peering under the leaves I could see little limpet-like bumps on the branches and trunk of the tree. A couple of years ago I had had the same problem with my Viburnum bodnantense so I knew it was a type of scale insect.
Scale insects suck the sweet, sugary sap from plants, weakening the plant and possibly transmitting viruses. They start life as eggs and then hatch into their nymph stage where they look a little like aphids. These nymphs crawl over the plant looking for somewhere to settle and develop into a scale where there will sit happily sucking on the carbohydrates flowing around the plant just below the surface of the branch. Eggs are then laid under the protective surface of the scale.
Now is the perfect time to go out and check over your plants for any pests like this. Plants are putting on a lot of growth at the moment, especially with all this rain. This new growth is particularly sweet and juicy and has yet to toughen up so it is a prime target for pests. When looking for pests like this start with the new leaves and buds. Aphids, in particular, love this fresh, new growth.
As for dealing with them. The scale itself protects the insect and any sprays are most effective when used on the egg or nymph stage. You could use a systemic pesticide, sprayed on the leaves it is absorbed by the plant and carried throughout the plant, as the pests eat the plant they absorb the chemical and die. There are natural pesticides, such as fatty acid sprays but these need to be used regularly because they don’t persist on the plant for a long period of time and are not suitable for the scale stage of the insect.
I garden organically though and the best way to deal with pests like this is with your fingers. It is, I have to admit pretty disgusting. You can use an old toothbrush, just dipped in some water and then run up and down the affected branches and this is what I started doing. My acer is a bit more delicate than the Viburnum though and after a while I gave up with the toothbrush and resorted to the good old ‘finger squishing’ technique. Messy yes, but effective. As I was scouring the plant for any more signs of scales I also spotted some of the nymphs congregated on the leaves so these were squished, too. I’ll keep an eye on the tree over the next month or so.
Scale insects are quite common on greenhouse and conservatory plants and because these protected spaces have good growing conditions they can survive all year having several generations of offspring.
I also spotted this …
Tasty Marsh Marigold
needless to say this slug didn’t last much longer!
i had a simar plroblem with this last year on my magnloia and i used the finger squash move too, not pleasent but very affective.
as slugs go i let the chickens out into the garden foe 10 mins this sorts out my slug problem!!
Hi Stacey, I agree not pleasant but it really is the best way. Although it took days of scrubbing to get my fingers clean …yuk! No space for chickens here unfortunately, maybe you could hire yours out as like a crack team slug eating squad. Send them into peoples gardens for half an hour.
How horrible! I too use the squishing method on pests in the garden, at the moment the dreaded lily beetle, masses of pollen beetles especially on rosa Molineux and there are already some Lavender beetles. Christina
What’s the organic way against slugs? the one that works??
Hi Crafty plotter, Standing on them, cutting them in half with scissors, collecting them and putting them into salty water. These are the ones I employ. I will sometimes use the ‘organic’ slug pellets. Other than that accept them as best I can.
Wow, I’ve never seen scale insects. Slugs, yes. Hope your plants appreciate your efforts and they recover. Thanks for the picture.
Hi Judy, Wish I had never seen them either!!! Checked over the acer yesterday and it looks like I got them all so fingers crossed the plant doesn’t become sick.
I thought it was a little army of snails marching up the branch of your acer when I first looked at it. I just can’t bring myself to use the finger squishing method no matter how much I try, I usually get my hubby to carry out the necessary instead. My marsh marigold has gone made this year, nearly taking over my small pond. I’m so pleased when plants come back really healthy the following year.
Hi Jo, I’m really pleased with my marsh marigold. I love the brilliant yellow of the flowers. They’ve been so cheerful to look at over the last couple of weeks when it has been so dull.
After all the rain we’ve had, my garden is Slug Central! I’m putting on my wellies and squishing gloves….
Hi Deborah I’m finding slugs everywhere too. My method is stamping on them or if necessary scissors to snip them. My husband can’t do it but then as I point he hasn’t spent the last 3 months nurturing the plants only to see them mauled. I don’t like killing creatures but what else can you do?
I’m an organic gardener, but I admit to resorting to slug killing chemicals on occasion. My dahlias are full of little holes…
Well timed advice WW. Have never seen as many lily beetles before as I have done in the last week and now have spotted aphids in the greenhouse. It’s a constant battle of wills.
I also have an issue every year with a few ornamental trees and this may be exactly what it is…I will keep a look out for it.
Hi Donna, They’re awful things… yuk!!
It feels that everything is being thrown at us this spring – or am I just being paranoid? I’ve found both scale insect and woolly aphid in the greenhouse for the first time. And the rain! Surely the water companies must soon be satisfied? Might just get myself a nice office job.
Hi David, I sympathise, I’m sure I’m going to develop webbed feet if this rain continues. Apparently it needs to rain like this all summer to make up for the shortfall of the past 2 years!! It does feel quite demoralising sometimes. The slugs are rampant and have mauled my sweet peas which I have nurtured since February. I don’t like using slug pellets but I have put some of the supposedly organic ones out. It’s just so wet though and there’s thousands of the things. I really feel for the farmers at the moment. They had to call off the Asparagus Festival last weekend because it’s been so cold the crops aren’t growing.
When we had a lemon tree, I had to be on scale insect patrol, absolute nuisance they were! I found that squishing is the only organic way although I have read that applying metholated spirits with cotton wool is supposed to work if you are a bit squeamish!
I’m a little squeamish, Pauline but sometimes just getting stuck in is the best way. It took days to get the staining from my fingers despite a furious amount of scrubbing!