LET’S INVITE LEAFCUTTER BEES INTO OUR GARDENS
Yummy, yummy! Is the phrase that comes to our minds when remembering Winnie the Pooh eating all those pots of honey. Many of us may only have thought about honey bees for the first time when we were kids, thanks to that cute bear with the sweet tooth. Then we learned that we are not only indebted to honey bees for the wonderful miracle of honey, but also for the privilege of eating many of our delicious vegetables and fruits every day. Yes! Honey bees are one of the most important pollinators of the crops that we the humans use all the time!
Some of us got so enthusiastic about this insect that we fell in love with it and became backyard beekeepers — we spend hours watching them buzzing around our sunflowers, pumpkins, lemons, sage and many other beautiful plants in our gardens.
What many of us do not know however, is that there are other bees that can live and work in our gardens — and perform very important roles within them.
Leafcutter Bees are very interesting solitary bees. They belong to the family Megachilidae and they nest inside cavities building their egg cells with pieces of leaves. They build multiple egg chambers per nest hole and in every one of them they deposit an egg with a little bit of pollen, nectar and saliva for the further development of the larvae.
Megachilidae are wonderful insects. Watching them carrying leaves and working to cover their nests is very beautiful, but they are also very important pollinators of crops like clover, alfalfa, fruits, some vegetables — such as onions and carrots — flowers and wildflowers.
You probably don’t know it… but the lucerne leafcutting bee (Megachile rotundata) was introduced to New Zealand from North America in 1971 for management as a specialist pollinator of lucerne flowers for production of seed. For more information
Several years ago interest in leafcutting bees (and other species of bees) began increasing again because of the threats facing honey bees, and so efforts are being made to increase the numbers of leafcutting bees in New Zealand for wider distribution to home gardeners. Leafcutting bees can be valuable pollinators of a range of flowers, and because the females are not aggressive and the bees can be easily managed, they can be readily utilized by home gardeners and owners of small holdings for increased pollination, educational interest and fun.
How can you recognise leaf cutter bees? They are the size of a honey bee and for an untrained eye they look very similar, but here is the tip: while honey bees carry pollen in their corbicula (special structures in the tibia of the hind leg), leaf cutter bees carry the pollen that they collect on their scopa (elongated hairs on the abdomen). Also, many times you will see these bees carrying parts of leaves back to their nest and honey bees do not have this behaviour.