Pollination Management - Importance of Pollination Management

Importance of Pollination Management

The increasing size of fields and orchards (monoculture) increase the importance of pollination management. Monoculture can cause a brief period when pollinators have more food resources than they can use, while other periods of the year can bring starvation or pesticide contamination of food sources. Most pollinator species rely on a steady nectar source and pollen source throughout the growing season to build up their numbers.

Crops that traditionally have had managed pollination include apple, almonds, pears, some plum and cherry varieties, blueberries, cranberries, cucumbers, cantaloupe, watermelon, alfalfa seeds, onion seeds, and many others. Some crops that have traditionally depended entirely on chance pollination by wild pollinators need pollination management nowadays to make a profitable crop.

Some crops, especially when planted in a monoculture situation, require a very high level of pollinators to produce economically viable crops. This may be because of lack of attractiveness of the blossoms, or from trying to pollinate with an alternative when the native pollinator is extinct or rare. These include crops such as alfalfa, cranberries, and kiwifruit. This technique is known as saturation pollination. In many such cases, various native bees are vastly more efficient at pollination (e.g., with blueberries), but the inefficiency of the honey bees is compensated for by using large numbers of hives, the total number of foragers thereby far exceeding the local abundance of native pollinators. In a very few cases, it has been possible to develop commercially viable pollination techniques that use the more efficient pollinators, rather than continued reliance on honey bees, as in the management of the alfalfa leafcutter bee.

Number of hives needed per unit area of crop pollination

Common name	number of hives per acre	number of hives per hectare	number of bee visits per square meter/minute
Alfalfa	1, (3–5)	2.5, (4.9–12)
Almonds	2–3	4.9–7.4
Apples (normal size)	1	2.5
Apples (semi dwarf)	2	4.9
Apples (dwarf)	3	7.4
Apricots	1	2.5
Blueberries	3–4	7.4–9.9	2.5
Borage	0.6–1.0	1.5–2.5
Buckwheat	0.5–1	1.2–2.5
Canola	1	2.5
Canola (hybrid)	2.0–2.5	4.9–6.2
Cantaloupes	2–4, (average 2.4)	4.9–9.9, (average 5.9)
Clovers	1–2	2.5–4.9
Cranberries	3	7.4
Cucumbers	1–2, (average 2.1)	2.5–4.9, (average 5.2)
Ginseng	1	2.5
Muskmelon	1–3	2.5–7.4
Nectarines	1	2.5
Peaches	1	2.5
Pears	1	2.5
Plums	1	2.5
Pumpkins	1	2.5
Raspberries	0.7–1.3	1.7–3.2
Squash	1–3	2.5–7.4
Strawberries	1–3.5	2.5–8.6
Sunflower	1	2.5
Trefoil	0.6–1.5	1.5–3.7
Watermelon	1–3, (average 1.3)	2.5–4.9, (average 3.2)
Zucchini	1	2.5

It is estimated that about one hive per acre will sufficiently pollinate watermelons. In the 1950s when the woods were full of wild bee trees, and beehives were normally kept on most South Carolina farms, a farmer who grew ten acres (4 ha) of watermelons would be a large grower and probably had all the pollination needed. But today's grower may grow 200 acres (80 ha), and, if lucky, there might be one bee tree left within range. The only option in the current economy is to bring beehives to the field during blossom time.

See also: List of crop plants pollinated by bees