This article is the second in a three-part series on almond production in California. Read the first installment: Almond farmers fuel innovation, find solutions.
Although almond farmers work throughout the year to prepare their crops, they depend on bees to pollinate their trees and allow them to bear almonds. In addition to the bees, an orchard of diverse varieties is important for cross-pollination.
Almond farmer Tom Rogers, owner of a 170-acre orchard in Madera, receives bees from a beekeeper in Colorado. About five years ago, the beekeeper hired by Rogers encountered a problem leading to the deaths of his bees.
Rogers said he scrambled to find a new beekeeper and was fortunate to obtain bees in a short period of time.
“He [beekeeper] does all of the extra feedings and does what he can to protect the bees, because it’s a very little mite that gets in the stomach of the bees [and kills them],” Rogers said. “He’s found some things that work, but it’s the same thing like humans: If you over-medicate them, you kill them.”
As spring approaches, the bees begin to arrive so they can get acclimated to the environment. Soon after, the bees start pollination and continue for a few months. The temperature at which bees come out of their hive corresponds to the soil viability, 56 degrees Fahrenheit.
“They [bees] are amazing animals; they come out at 56 degrees,” Rogers said. “And almond blooms are only viable above 56 degrees, so God kind of knew what he was doing when he put everything together. Below that, the pollen is not viable, so there is no reason for the bees to be out if you’re not going to gain anything.”
Conditions for pollination
The bees cannot pollinate the nuts without there being two varieties of almonds in the orchard. For example, a Nonpareil will pollinate with a Carmel, and a Butte with a Padre. In addition, there are other variations of cross-pollination, such as a Butte with a Nonpareil; but a Butte cannot cross with a Carmel.
In the last few years, universities have done studies to determine if pollen from one tree can accommodate another, according to Rogers. Therefore, farmers not only match trees corresponding with bloom time but also with their ability to cross-pollinate.
The university standard for pollination is that there be two hives per acre of bees, each hive containing eight frames. Even though the requirement is two hives per acre to acquire crop insurance, some farmers have realized that if the bees are hard-working, fewer are needed.
“We’re watching the cost of the hives go up and we’re trying to watch our cost,” Rogers said. “So we are experimenting by cutting back a little bit. I know last year we had excellent bees. If you have a really good spring, you can get by with one hive per acre, great weather and plenty of time. It’s when you have a short bloom and cold weather, the more the merrier.”
Within a hive, frames range from four to 14, but typically maintain a consistent number of 10 frames. According to Rogers, bees work more effectively when their hive contains more frames.
“You can cut back a little bit, but bees work exceptionally more with the higher number of frames,” Rogers said. “If you get down to four frames, they won’t hardly come out of the box; at six, they start moving; eight, they are pretty strong; but at 10, you can’t believe the activity. In our box of bees there is about 12-14 frames [sic].”
Handling pest, fungus hazards
While farmers may struggle to have enough bees for pollination, they must also deal with the issue of pests. In the past few years, mites such as the European red and two-spotted spider have become a problem for local farmers.
“Seven or eight years ago, we didn’t have problems; but [over] the last few years it has been a major issue,” Rogers said. “We are using some products preventively, and they have been working pretty well for us. But we had a couple of years where these orchards looked horrible because they [trees] were just dropping leaves.”
According to Rogers, some relatively warm winters have prevented the mite population from decreasing. As a result, farmers are having to deal with a greater number of mites.
“There are more trees around, so we provide more hosts for the mites,” Rogers said. “And we have not really had cold winters, and that is what really suppresses the pests; we’ve had cold snaps, but we really need an extended period.”
Another obstacle growers encounter is fungus, which poisons the flower and causes it to fall from the tree. To prevent the occurrence of fungus, farmers spay their trees two or three times a year.
“We are very conscious of what we use,” Rogers said. “There are ways to get around that [causing harm to bees] because bees will only come out above 56 degrees, so we get all the spraying done before. We use air-blast sprayers, so if you drive by a beehive, it upsets them. Their focus is to protect the hive, so if you spray them, it will disrupt the hive, and they will also chase after you.”
A bout with less-friendly bees
According to Rogers, about three years ago a neighbor encountered problems with Africanized bees, which are more agressive than typical honeybees.
“There was one guy who didn’t think he was going to make it because he accidentally bumped a box, and they [Africanized bees] chased him a good 300-400 yards,” Rogers said. “I don’t think they were 100-percent African, but they had it in them. It was scary.”
For more information on bees, read the Dec. 7, 2010 article, Honeybees critical to Valley agriculture. For more information on almonds, read the Feb. 17 article, Almond farmers fuel innovation, find solutions.
