Monday 22 June 2020

Aphids, Aphids Everywhere!



Have you ever grown broad beans and found the minute you turn your back in Spring the flowers and plants are covered in blackfly? Just when the runner beans are starting to shoot and twist their way to the sky, the same little bugs take up residence.

Where do they come from and why is it my plants they attack?

Out comes the spray and washing up liquid and so starts a battle of wits and survival between these little beasts and me that is repeated all spring and summer.

Aphids can be every colour imaginable. We may be used to the green and black varieties but there some 4,400 species in the world; yellow, orange, red, blue, purple, brown varieties, all designed to suck the sap out of whatever they fancy and eat at your or others’ plots.

Aphids have a soft body, small eyes, large antennas, three pairs of legs and a mouth designed for sucking. Most species are wingless and they eat both during the day and night. 

‘Why are you spraying your beans? Shouldn’t you be watering them so we can go home?’ my faithful allotment whippet Lottie asks from her pillows on the bench.

‘Killing the blackfly.’ I respond.

‘But even I know the ladybirds and others do that for you. Even the ants are often busy scurrying up and down your beans and coming down dribbling their food and with fat bellies.’

‘The ants don’t eat the bugs, they eat their poo’ I reply watching Lottie give an expression of disgust.

‘They eat their poo?’

I can see this is going to be a long discussion and one of those where she either gets bored or I simply run out of answers to her endless questions.

‘Ants extract sap out of the plant which is very high in sugar. The bugs get little from the sugar so poo it out as droplets we call honeydew and ants love sugar feed on that.’ I look at a smiling Lottie who can’t wait to respond.

‘So, they are like vacuum cleaners or dustmen cleaning up after the bugs?’

‘Yes, and the ants even protect the aphids from some predators and some aphid-herding ants will adopt the aphids and take them back to their nest during winter. They even carry them from plant to plant so they can ‘milk’ them and feed off their honeydew.’ I think that will give Lottie something to think about and allow me to get back to my work.

A short while later Lottie pipes up, ‘You should find their nests and spray their eggs.’

‘They don’t lay eggs as such. They reproduce without mating and the females give birth to live young and at a phenomenal rate,’ I tell Lottie who is now clearly interested to know more.

‘So how do they move so quickly from plant to plant?’   
‘They can produce a generation of alates, or winged adults, capable of flight and scouting out the next best plant on which to deposit the females and they simply take up residence, start to feed and multiply.’

‘Then go after the flyers’ suggests Lottie.

‘I would if I could’ I reply, swatting a green flyer who was foolish enough to land on my arm.

‘You never see Monty Don spraying his bugs’ Lottie offers changing the subject.

‘Ah well that might not be good TV and very PC. He probably has a small army of helpers off camera doing it for him. After all, no garden is bug free’ I reply.

‘Robin doesn’t eat them?’

‘No.’

Then Lottie flops back down onto her pillow clearly bored with aphids. ‘I bet they are not an endangered species and it certainly is a Bug’s Life.’