A honeybee takes flight on the roof of Hirshfield's, Inc. warehouse in downtown Minneapolis. Honeybees are capable of flying up to five miles to forage for food in urban gardens, but usually only need to travel a mile or two. Linden trees, unmown clover and flowers are all good food sources. Judy Griesedieck / For MPR News

The U.S. Department of Agriculture is expanding a program to create new habitat for bees in five states, including Minnesota.

The pilot program started earlier this year with $3 million, but demand far outstripped the funding. The effort, which also includes Michigan, North Dakota, South Dakota and Wisconsin, will get another $4 million.

Farmers can use the money to plant wild flowers that enhance bee nutrition, said Kirk Hanlin, assistant chief for the USDA's Natural Resources Conservation Service.

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"Almost 65 percent of commercially managed honeybees in the entire country are in those five states between June and September, so by concentrating the effort in those five states you can actually have a huge impact on the honeybee population," he said.

More than one third of honeybees died each winter in recent years. Research continues on what's causing the losses, but more food on the landscape will help bee health, Hanlin added.

USDA says an estimated $15 billion worth of crops is pollinated by honey bees, including more than 130 fruits and vegetables.