Bees are essential for agriculture because they pollinate crops. Many crops are wind pollinated and orchards are propagated through grafts, but bees still pollinate a large number of crops. A growing concern in the world today is the disappearance of bee colonies.
One of the potential reasons for bee extinction is that we’re spraying new pesticides called neonicotinoids on crops. It causes bees to become disorientated and in high enough doses, can kill them. Not all scientists agree with this, however.
Some mites are now resistant to pesticides and continue to eat crops. This makes it difficult for bees to find pollen. Also new viruses are appearing in bees. So it’s a combination of factors that are driving the bee population down.
In a normal year, 5 to 10 % of hives are lost due to the bees dieing. Lately it’s been more like 40 %. This is a real concern to both apiarists and growers because it impacts their businesses. Less hives also push up the price of hives, which puts upwards pressure on food prices.
In a world running out of food, we need everything we can do to supply the world’s growing hungry population. There are many ways we can do this. Reducing our reliance on herbicides and pesticides will result in healthier bees and healthier crops.
Urban farming minimises the use of pesticides and herbicides because most urban farmers are not trained in the handling of these chemicals. Furthermore, they’re an expense that most urban farms don’t need to incur.
You can read more about this problem at the New York Times: http://www.nytimes.com/2013/03/29/science/earth/soaring-bee-deaths-in-2012-sound-alarm-on-malady.html?pagewanted=all&_r=0