Research Shows Number of Bees, Not Number of Species, Improves Pollination

By Michael Hill

A simple question about what matters most for pollinating plants and crops so pick-your-own customers and the world can have fresh fruit, vegetables and flowers: to be abundant with many kinds of wild bees or to be abundant with lots of wild bees.

“And it turns out the answer is mostly the latter, not completely, but mostly. To a first approximation, just having a lot of the wild, native bees on your farm will be giving you a lot of crop pollination,” said Rachael Winfree.

For two years, Rutgers ecologist Winfree and a research team studied three New Jersey farms — one with blueberries, one with cranberries and Honey Brook Organic Farm’s watermelon patch.

There’s a reason this farm was ripe for Dr. Winfree and others to do their research. The bees are plentiful. Just beyond this farmed land is a nature preserve, untouched land, a wild habitat, perfect for the growth of wild bees.

“I think we found about 50 species on this farm here,” Winfree said.

But, Dr. Winfree says an analysis of the melons showed not all kinds of pollinators or bees are equal.

“There are some bee species that are super abundant. There’s one bumblebee in particular, called ‘Bombus impatiens,’ a very common bumblebee, it’s an excellent pollinator, and it might be easily half of the individual bees we would find on a given farm. So, if that’s the case, it’s pretty likely the case that a few species are enough to do a lot of your pollination,” she said.

Dr. Winfree and a Dutch counterpart say they found the same conclusion worldwide after reviewing some 60 bee studies: 2 percent of the bees do 80 percent of the pollination.

At Honey Brook, co-owner Sherry Dudas said, “We have been farming this land now for 25 years. So, we’ve been aware of the native bees and the other native pollinators. We just didn’t know how important they were to our farm.”

Dudas says the family grows zinnias to sell and to attract wild bees. She says it grows some plants just for the bees and Honey Brook takes an organic approach — such as its barn swallow habitat — to control insects. She and Dr. Winfree say that and fields of a wide variety of fruits, vegetables, herbs and flowers make this a haven for some wild, native bees.

“So a farm like this one is sort of a smorgasbord for bees because it has all these things coming into bloom at different times. That’s great as far as they’re concerned,” Winfree said.

“I feel that this is increasingly interesting and valuable information for all farmers,” Dudas said.

Both hope the research creates more than just a buzz about the bees.