Squash Bees

Checkout These Wild Pollinators

by Sandy Swegel

My friend and local pollinator expert Niki fretted greatly this Spring because there weren’t any bees in her yard.  She grows her native plants and large vegetable gardens in her yard that is surrounded by typical perfect looking suburban lawns. Despite her pleas with neighbors, they maintain suburban perfection by pouring pesticides and synthetic fertilizers on their lawns, and over time, the bee count in her yard has dropped precipitously.

But there was no fretting during a recent tour of her garden.  There were still very few honeybees but the garden was abuzz with many native bees and native fly pollinators.

Niki eagerly led us over to her huge squash patch.  She did the usual humble gardener thing of apologizing for her garden and how poorly the plants were doing.  Naturally, her plants were double the size of anything in our yards. We walked right into the squash bed as she gently lifted a giant leaf so we could see…a “Squash Bee.”  With great animation, she described how one bee comes early in the morning and throws itself completely over the pollen…and then proceeds to eat all day long.  This bee seems oblivious to us and looked like it was lounging in its own little opium den, covered in pollen and eating as much as it could. Niki lowered her voice and said, “Sometimes there are two bees.”  The male comes first and then is joined by a female…and the two of them spend the day in a frenzy of mating and eating, mating and eating (she watched). Once they finish one blossom, they moved to the next one.

There are two genera of native squash bees, Peponapis and Xenoglossa, and they are specialist bees. Cucurbits are all they pollinate.  And they are very resourceful and start pollinating earlier in the morning before the honey bees are even awake.  So take a look under your leaves one morning and peer deep into squash blossoms.  In areas with healthy squash bee populations, there can be as many as one bee per every five blossoms.  Another marvel of the natural world….hidden in plain view before us.

Of course, while you are peeking under giant squash leaves, don’t forget to look for that pest of the squash kingdom…the squash bug…and pick it off and throw it away.

The International squash bee survey: http://www.ars.usda.gov/Research/docs.htm?docid=16595