The most important agricultural product in California is the almond crop. Centered in the Northern part of that state, bees are brought in from many states to pollinate the rapidly expanding acreage of orchards. Faced with diminishing supply of bees and water for irrigation during the drought, growers try to match the number of hives (colonies) per acre with profitable nut crop production. Growers insurance policies will usually not pay up for losses if less than 2 hives/acre are contracted to be used. Some growers use 2.5 or 3 hives/acre especially if they don’t have strong colonies or compensate for poor weather.
Season for pollination is from February to March depending on crop variety, and weather conditions. Effective blooming period can be from 3 to 10 days and usual flight time is from 10 a.m. to 2 p.m. each day. A 3,000 lb crop has 1 million nuts (350 nuts/lb). Assuming a 50 percent set of flowers it would take 2 million flowers to provide a 3000 lb crop. Colony strength needs to be at least four frames covered with bees and price paid per hive varies from $165/4-6 frames to $225/ 8-10 frames.
A frame of bees contains 1,500 bees. An 8 frame colony contains 12,000 bees, a third of these are foregers. Calculating all these data and estimating unknowns (like weather) make it hard for the grower to ensure a profitable crop. There is however, a quick and easy way to demonstrate whether or not enough bees are used in the orchard.
Using strong colonies, bees collect the daily ration of pollen provided by almond flowers by 2 p.m., or sooner. After 2 p.m. the grower walks the orchard and rubs the anthers of the flowers with fingers. There should be little or no pollen on fingers — and the bees should have done their job for the day and the grower knows that he has enough hives/acre for a good crop.
After 2 p.m. it is normal to see increased activity with lots of bees covering the blossoms. More bees /tree than earlier they are not gathering pollen. Observing the bees on flowers will show that the tongues are drinking nectar from the base of the flower. Almond flowers increase the nectar flow only after the blossom has been pollinated and this has invited the thirsty nectar gathering bees.
Most growers allow the hives used for pollination to remain in the orchard after the pollen crop is gone. The almond nectar furnishes the bee keeper with a valuable almond honey crop to sell or to feed back to bees while being moved to cherries and apples in Washington or to Canada for canola season starting early April. Many beekeepers keep their bees working all summer to earn pollination fees and to have a honey crop to sell in the fall.
Source - http://www.thedailymail.net/
