A bee collects pollen at the Alnwick Gardens amid reopening preparations after the lockdown of the coronavirus disease (COVID-19) outbreak, in Northumberland, Britain, June 30, 2020. REUTERS/Smith Lee

A bee collects pollen at the Alnwick Gardens amid reopening preparations after the lockdown of the coronavirus disease (COVID-19) outbreak, in Northumberland, Britain, June 30, 2020. REUTERS/Smith Lee

A bee collects pollen at the Alnwick Gardens amid reopening preparations after the lockdown of the coronavirus disease (COVID-19) outbreak, in Northumberland, Britain, June 30, 2020. REUTERS/Smith Lee

A bee collects pollen at the Alnwick Gardens amid reopening preparations after the lockdown of the coronavirus disease (COVID-19) outbreak, in Northumberland, Britain, June 30, 2020. REUTERS/Smith Lee

A bee collects pollen at the Alnwick Gardens amid reopening preparations after the lockdown of the coronavirus disease (COVID-19) outbreak, in Northumberland, Britain, June 30, 2020. REUTERS/Smith Lee

A bee collects pollen at the Alnwick Gardens amid reopening preparations after the lockdown of the coronavirus disease (COVID-19) outbreak, in Northumberland, Britain, June 30, 2020. REUTERS/Smith Lee

People paddle through a pollen patch on Lake Leman in Villeneuve, Switzerland May 10, 2020. REUTERS/Denis Balibouse

People stand on a pontoon above an accumulation of pollen on Lake Leman in Villeneuve, Switzerland May 10, 2020. REUTERS/Denis Balibouse

An accumulation of pollen is pictured on Lake Leman in Villeneuve, Switzerland May 10, 2020. REUTERS/Denis Balibouse

An accumulation of pollen is pictured on Lake Leman in Villeneuve, Switzerland May 10, 2020. REUTERS/Denis Balibouse

People walk on a pontoon above an accumulation of pollen on Lake Leman in Villeneuve, Switzerland May 10, 2020. REUTERS/Denis Balibouse

People paddle through a pollen patch on Lake Leman in Villeneuve, Switzerland May 10, 2020. REUTERS/Denis Balibouse

A bee covered with pollen hooks itself onto a petal of a bluebell in a garden, as the spread of the coronavirus disease (COVID-19) continues, in West London, Britain, April 23, 2020. REUTERS/Toby Melville

A bee covered with pollen hooks itself onto a petal of a bluebell in a garden, as the spread of the coronavirus disease (COVID-19) continues, in West London, Britain, April 23, 2020. REUTERS/Toby Melville

A tractor pulls a mast equipped with small cannons that shoot pollen at almond trees, allowing them to fertilize without bees in an Almonds grove in Tel Arad, southern Israel March 4, 2020. Picture taken on March 4, 2020. REUTERS/ Amir Cohen

A tractor pulls a mast equipped with small cannons that shoot pollen at almond trees, allowing them to fertilize without bees in an Almonds grove in Tel Arad, southern Israel March 4, 2020. Picture taken on March 4, 2020. REUTERS/ Amir Cohen

Tractors pull a mast equipped with small cannons that shoot pollen at almond trees, allowing them to fertilize without bees in an Almonds grove in Tel Arad, southern Israel March 4, 2020. Picture taken on March 4, 2020. REUTERS/ Amir Cohen

"Reachy," an open-source robot by Pollen Robotics, displayed at CES Unveiled during the 2020 CES in Las Vegas, Nevada, U.S. January 5, 2020. REUTERS/Steve Marcus

Bees are seen on a honeycomb at an apiary, in Casablanca, Chile October 4, 2019. Picture taken October 4, 2019. REUTERS/Rodrigo Garrido

Bees are seen at an apiary, in Casablanca, Chile October 4, 2019. Picture taken October 4, 2019. REUTERS/Rodrigo Garrido

A queen bee is seen on a honeycomb at an apiary, in Casablanca, Chile October 4, 2019. Picture taken October 4, 2019. REUTERS/Rodrigo Garrido

Bees are seen on a honeycomb at an apiary, in Casablanca, Chile October 4, 2019. Picture taken October 4, 2019. REUTERS/Rodrigo Garrido

A bumblebee collects nectar from a flower, in Vina del Mar, Chile October 13, 2019. Picture taken October 13, 2019. REUTERS/Rodrigo Garrido

Bees are seen on a beekeeper's finger at an apiary, in Casablanca, Chile October 4, 2019. Picture taken October 4, 2019. REUTERS/Rodrigo Garrido

A bumblebee collects nectar from a flower, in Vina del Mar, Chile October 13, 2019. Picture taken October 13, 2019. REUTERS/Rodrigo Garrido

A bumblebee collects nectar from a flower, in Vina del Mar, Chile October 13, 2019. Picture taken October 13, 2019. REUTERS/Rodrigo Garrido

Moose, a six-year-old English Bulldog with B-cell lymphoma, receives trial medical treatment at Cummings School of Veterinary Medicine at Tufts University by vet technicians Stephanie Pollen (L) and Michele Willett in North Grafton, Massachusetts, U.S., September 13, 2019. Photograph taken September 13, 2019. REUTERS/Katherine Taylor

Moose, a six-year-old English Bulldog with B-cell lymphoma, and his owners Eric (2nd L) and Jessica Lescault are met by vet technician Stephanie Pollen (L) before Moose’s trial medical treatment at Cummings School of Veterinary Medicine at Tufts University in North Grafton, Massachusetts, U.S., September 13, 2019. Photograph taken September 13, 2019. REUTERS/Katherine Taylor

A bee collects pollen at a flower near a Deutsche Bank office in London, Britain July 8, 2019. REUTERS/Simon Dawson

A bee deposits pollen in a honeycomb in La Bollene Vesubie, France, July 2, 2019. Picture taken July 2, 2019. REUTERS/Eric Gaillard

A bee deposits pollen in a honeycomb in La Bollene Vesubie, France, July 2, 2019. Picture taken July 2, 2019. REUTERS/Eric Gaillard

A bee deposits pollen in a honeycomb in La Bollene Vesubie, France, July 2, 2019. Picture taken July 2, 2019. REUTERS/Eric Gaillard

Tennis - Wimbledon - All England Lawn Tennis and Croquet Club, London, Britain - July 3, 2019 Bee seen getting pollen from a flower as Taiwan's Hsieh Su-wei plays her second round match against Belgium's Kirsten Flipkens in the background REUTERS/Toby Melville

Tennis - Wimbledon - All England Lawn Tennis and Croquet Club, London, Britain - July 3, 2019 Bee seen getting pollen from a flower as Taiwan's Hsieh Su-wei plays her second round match against Belgium's Kirsten Flipkens in the background REUTERS/Toby Melville TPX IMAGES OF THE DAY

Tennis - Wimbledon - All England Lawn Tennis and Croquet Club, London, Britain - July 3, 2019 Bee seen getting pollen from a flower as Taiwan's Hsieh Su-wei plays her second round match against Belgium's Kirsten Flipkens in the background REUTERS/Toby Melville

The queen bee is seen on the frame of a hive in a village of Ripanj near Belgrade, Serbia, April 9, 2019. Picture taken April 9, 2019. REUTERS/Marko Djurica

Bees are seen on the frame of a hive in a village of Ripanj near Belgrade, Serbia, April 9, 2019. Picture taken April 9, 2019. REUTERS/Marko Djurica

The queen bee is seen on the frame of a hive in a village of Ripanj near Belgrade, Serbia, April 9, 2019. Picture taken April 9, 2019. REUTERS/Marko Djurica

A bee collects nectar from a flower in a village of Ripanj near Belgrade, Serbia, April 9, 2019. Picture taken April 9, 2019. REUTERS/Marko Djurica

A bee collects nectar from a flower in a village of Ripanj near Belgrade, Serbia, April 9, 2019. Picture taken April 9, 2019. REUTERS/Marko Djurica

A bee collects nectar from a flower in a village of Ripanj near Belgrade, Serbia, April 9, 2019. Picture taken April 9, 2019. REUTERS/Marko Djurica

A bee is seen on the frame of a hive in a village of Ripanj near Belgrade, Serbia, April 9, 2019. Picture taken April 9, 2019. REUTERS/Marko Djurica

A bee collects nectar from a flower in a village of Ripanj near Belgrade, Serbia, April 9, 2019. Picture taken April 9, 2019. REUTERS/Marko Djurica

A bee collects nectar from a flower in a village of Ripanj near Belgrade, Serbia, April 9, 2019. Picture taken April 9, 2019. REUTERS/Marko Djurica

A bee is seen on the frame of a hive in a village of Ripanj near Belgrade, Serbia, April 9, 2019. Picture taken April 9, 2019. REUTERS/Marko Djurica

Bees are seen on the frame of a hive in a village of Ripanj near Belgrade, Serbia, April 9, 2019. Picture taken April 9, 2019. REUTERS/Marko Djurica

A bee is pictured during a cherry blossom season on a street at Berlin's Lichterfelde district, Germany, March 30, 2019. REUTERS/Fabrizio Bensch

A bee is pictured during a cherry blossom season on a street at Berlin's Lichterfelde district, Germany, March 30, 2019. REUTERS/Fabrizio Bensch

A bee searches for pollen among cherry blossoms on a sunny spring day in Lausanne, Switzerland March 25, 2019. REUTERS/Denis Balibouse

A bee searches for pollen among cherry blossoms on a sunny spring day in Lausanne, Switzerland March 25, 2019. REUTERS/Denis Balibouse

A bee takes pollen from a spring bloom in St James's Park in London, Britain, February 25, 2019. REUTERS/Toby Melville

A bee takes pollen from a spring bloom in St James's Park in London, Britain, February 25, 2019. REUTERS/Toby Melville

An insect collects pollen in Vertou, near Nantes, France, September 10, 2018. REUTERS/Stephane Mahe

An insect collects pollen in Vertou, near Nantes, France, September 10, 2018. REUTERS/Stephane Mahe

A hornet is seen in Vertou, near Nantes, France, September 10, 2018. REUTERS/Stephane Mahe

An insect collects pollen in Vertou, near Nantes, France, September 10, 2018. REUTERS/Stephane Mahe

An Asian hornet, Latin name "Vespa Velutina", is seen in Vertou, near Nantes, France, September 10, 2018. REUTERS/Stephane Mahe

An Asian hornet, Latin name "Vespa Velutina", is seen in Vertou, near Nantes, France, September 10, 2018. REUTERS/Stephane Mahe

An Asian hornet, Latin name "Vespa Velutina", is seen in Vertou, near Nantes, France, September 10, 2018. REUTERS/Stephane Mahe

A hornet is seen in Vertou, near Nantes, France, September 10, 2018. REUTERS/Stephane Mahe