Our garden in Herzliya looks beautiful and serene on a hot, summer day. But appearances are deceiving. Our beloved hibiscus hedge, the dense border screening us from the street, is under attack from opportunistic invaders. The Green Stalwarts, as we call our hibiscus, proudly wave their glorious colored flowers -- their flags of courage. Yet a battle has begun and I'm preparing our family to help.
The peaceful Green Stalwarts are a perfect target for attack and takeover; they provide a rich environment for opportunists seeking food and shelter. Thus, it's no surprise that we see White Vandals arriving from afar at sunrise every morning. TheWhite Vandals, known as mealy bugs[1], fly their stealth scouts to our peaceful haven settling on the youngest and juiciest buds of the Green Stalwarts. Their stealth campaign expands exponentially as they lay their eggs and grow into colonies of hundreds. Each Vandal soldier is protected by white, woolly armor that shields it from its enemies and from dehydration. Little by little the White Vandals suck the guts from the Green Stalwarts; their proud leaves wilt and those glorious flowers fall dead to the ground. Their bare branches bear witness to severe and possible fatal injuries. Picture 1 Yet, if the Green Stalwarts die, the White Vandals will have destroyed their food source and will be unable to move on to new, distant Greens.
But, wait! There are entrepreneurs in the garden who sense an opportunity. It seems the White Vandals are fortunate to have business partners. Soon we see huge numbers of Brown Traders[2], known as big-headed ants, heading into battle. They swarm out of their underground tunnels and march in neat lines up the Green Stalwarts' branches. By sheer numbers and brute force, the Brown Traders collect baby White Vandal eggs and carry them to new, juicy, vulnerable leaves. Thus, it's the Brown Traders who disperse the additional colonies. This is the deal: The Brown Traders exchange transportation services for sugar droplets manufactured by the White Vandals. The sugar is made from liquid that's sucked from the veins of the Green Stalwarts' leaves. The Brown Traders lick the sugar droplets and carry their booty to their underground nests to feed their own babies. Picture 2
It's a losing situation for the Green Stalwarts. They can't move away, and they look distressed and bare. They might not even make it through the summer.
Standing in the garden, considering the options, I decide that my plan of action will be entirely Israeli:
It will be a family project involving grandchildren
It will be exciting, inexpensive, targeted to the specific insect pest, using Israeli knowhow
Plant-insect relationships represent complex eco-systems. Most of us have read about the plight of bees worldwide – colony collapse disorder and its significance for crops. Many of us also are aware of a long-term decline of wild insect diversity that threatens birds, lizards and frogs who rely on them for food. There is no question that intensive spraying of crops and gardens with generalist pesticides that kill all insects are part of the problem.
Yet sometimes, as in my garden – and many areas throughout Israel – the insects do get seriously out of control and something must be done. I felt the time was right to do what I really believe in– biologically integrated pest management – the use of natural insect predators to control insect pests that damage plants. I wanted to try it so that we and the grandchildren could observe the process with our own eyes. Happily, one of the world leaders in this field is right here in Israel – BioBee at Kibbutz Sde Eliahu, near Beit Shean.
I rounded up the grandchildren, showed them the battleground, and explained that the White Vandals were about to meet their nemesis- Black Mercenaries, ordered from BioBee.
We received a refrigerated package of the Mercenaries[3], known as tropical lady beetles; they are relatives of the familiar orange spotted lady bugs. The Black Mercenaries are an incredibly motivated demolition team. Each tiny soldier is protected by a hard, black armor shield. Hidden under the shield, the transparent flying wings unfold from their neat origami package. We stood by the Green Stalwarts to open the tiny container with several hundred mercenaries inside. They were instantly on the wing. Using their specific, olfactory detectors, they infiltrated the White Vandal colonies and laid their own eggs among eggs of the White Vandals. Within days, baby mercenaries hatched and dispatched – with a surprising advantage. The babies were camouflaged to appear white and fluffy, just like the White Vandals. They marched rapidly from branch to branch and sucked out the innards of the White Vandals in their colonies. Like the wolf in sheep's clothing, they totally integrated with their enemy AND ate them up! Picture 3
The battle continued and after three weeks we saw evidence of victory. We swathe empty, white, fluffy armor of the vanquished White Vandal colonies waving in the breeze. Picture 4 The Green Stalwarts were growing new buds. The Black Mercenaries were winning!
Yet it is very difficult for the Black Mercenaries to gain absolute victory. The Brown Traders are crafty, even in the face of a variety of predators who seek to benefit from the spoils of war. While the Brown Traders deploy baby White Vandals to new places, there are spiders who weave elaborate nets to collect both flying White Vandals and Brown Traders. There are praying mantises that use strong, pincer-like arms to catch Brown Traders when they're on the march. And there is the ugly black mold that grows on the Green Native leaves, feasting on the sugar that was spilled by the Brown Traders.
Unfortunately, the Traders cannot be destroyed in a decisive victory without reaching them in their underground nests. Yet, the battle was won for the Green Stalwarts without resorting to underground warfare.
We declared a Blue and White Family victory. With just a little help and knowledge, we saved our beautiful hibiscus with the most benign impact on other insect inhabitants in the garden. We declared victory and enjoyed a symbiotic summer in our beloved ecosystem.
Amelia Terkel, PhD, is a retired Curator of the Ramat Gan Safari
[1] Planococcus Citri (Citrus Mealy Bug) and other mealy bugs
[2] Phaidole (Big-headed ant)
[3] Cryptolaemus Montrozieri (Tropical Lady Beetles)
For Further Reading:
BioBee Biological systems – BioBee: http://www.biobee.com BioBee Biological Systems is one of the leading international companies in the field of biologically based Integrated Pest Management, Natural Pollination, and Medfly Control.
Decline in insect biodiversity https://www.theguardian.com/environment/2017/oct/18/warning-of-ecological-armageddon-after-dramatic-plunge-in-insect-numbers
Ladybugs and Aphids: https://www.ceresgs.com/using-ladybugs-in-the-garden-and-greenhouse/