Cotton and Bees

Crops grown in today’s modern industrial agriculture employ improved seed, chemical pesticides and fertilizers, irrigation, and heavy machinery. Farmers are keenly aware of industrial agriculture’s impact on the natural world, and most producers are diligent stewards of the environment. They take great care in protecting their land and the wildlife that lives on it. Cathy Foust, Shelby County, Tennessee’s Extension Director, invited me to attend a presentation on protecting pollinators by Dr. Don Parker, Integrated Pest Management Manager with the National Cotton Council. Also attending were several other beekeeping friends, Richard Coy, president of Arkansas Beekeepers Association, Charles Force, president of Memphis Area Beekeepers Association, and Jon Zawislak, apiary instructor with University of Arkansas Extension Service. The audience of interested agricultural producers listened intently as Dr. Parker discussed the impact pesticides make on honey bees and native pollinators. Many of the producers were not aware that honey bees forage cotton fields. Some had not considered the effect of cotton insecticides on beneficial insects; they had only concentrated on killing pests. Cotton growers asked numerous questions of the beekeepers and seemed to be equally interested in protecting pollinators.

Dr. Parker spoke of some of the difficulties involved in protecting beneficial insects while trying to control pest insects with insecticides. One suggestion was to only apply insecticides at night while bees are not flying. Dr. Parker mentioned how dangerous it would be to fly a crop duster at night with cotton fields surrounded by trees and power lines. Such practices are completely unacceptable. Cotton growers and beekeepers were interested in discussions of the effect on beneficial insects when spraying insecticides on crop plants with “indeterminate growth” in which pollinators are continuously attracted by nectar. Here, bees can be poisoned even when the crop is not blooming. Other insecticide spraying challenges exist with plants, like cotton, which have “extrafloral” nectaries secreting nectar outside the flower. Today’s photo: a honey bee and a bumblebee, a native pollinator, share fall goldenrod near cotton fields.

--Richard

Abandoned Bee Hives

When honey bees swarm they frequently move into cavities previously used by other colonies of bees. They are attracted to old bee nests by hive odors of beeswax, honey, propolis, pollen, bees, and their pheromones. It is common for a colony of honey bees to occupy a hollow tree for a couple of years and then die after being weakened by parasitic Varroa mites. Even if the combs are destroyed by hive scavengers, like wax moths and small hive beetles, the cavity is likely to attract another colony of bees. The same sequence of events commonly occurs when people attempt to drive honey bees from the walls of their houses. Old colonies are soon replaced by new colonies. Colonies of bees replace one another so frequently that it may appear a hive is occupied continuously when it actually held a series of different colonies. The attractiveness of hive odors makes old bee hives effective bait hives for capturing swarms in the spring and summer. Old abandoned bee hives are attractive to swarming honey bees as well.

I received a call asking me to remove bees from some abandoned hives. I found a very large feral colony occupying a stack of rotting hive bodies. While wood rot and termites had consumed most of the woodenware, combs were held together by propolis. One by one, I transferred the frames of brood into new hive boxes. After all intact frames were moved, a number of broken pieces of brood comb remained. I placed these in a nucleus hive. After several weeks I found the feral queen hiding among the broken combs in the nucleus hive. The bees in the larger hive produced a new queen. I now have two strong hives with good behavior and characteristics. I welcome these locally-adapted feral genes into my bee yards. Was the colony in the abandoned hive equipment truly feral? Possibly, or its queen may have been purchased from a breeding program by another beekeeper. Lucky find.

--Richard

Parasitic Mite Syndrome

Beekeepers are detecting large populations of parasitic Varroa mites in their hives this fall. The Varroa mite is the most serious pest of honey bees in America. Though the mite weakens honey bees by sucking their blood, called hemolymph, they cause the most hive damage by spreading disease through the bee colony. Varroa mites reproduce inside the capped bee hive cells containing the pupa stage of developing bee brood. The parasitic mites pierce the exoskeleton of honey bees with their mouth parts to suck nutrients. The perforations caused by the mites allow entry of bacterial, fungal, and viral infections. At least 15 honey bee viruses are spread by Varroa mites. The combined effect of these honey bee diseases is known as Parasitic Mite Syndrome. Hives experiencing PMS often show reduced populations of bees as they decline and eventually collapse. One easily recognizable symptom of PMS is the existence of young bees in the hive with diminished, curled wings as the result of Deformed Wing Virus. Varroa mite populations increase steadily in bee hives anytime that bees are reproducing. Mite populations large enough to collapse colonies typically occur in the late summer and early fall. Beekeepers should measure mite populations and, if necessary, treat the hives with “soft” treatments of organic acids or essential oils.

Parasitic Mite Syndrome produces brood patterns with numerous empty cells as opposed to continuous patterns of capped cells. Some of the empty cells result from workers removing honey bee pupae that they detect having mites reproducing and developing with the bee pupae. This genetically heritable honey bee activity, known as “hygienic behavior,” is the basis for Varroa resistant honey bee stock. In today’s photo we see a brood frame from a hive showing signs of Parasitic Mite Syndrome. The brood pattern is “spotty;” a number of capped cells have been opened, and the bees are chewing out the pupae. Other hive conditions, such as American foulbrood and chilled brood, may have a similar appearance.

--Richard

Fall Bee Hive Management

In the fall it is important to look inside the bee hives and set them up for winter. Fall bee hive management is designed to help the bees survive the winter. This week I checked bee hives with Corinth, Mississippi beekeeper, Heidi Hendrix, and my 12-year-old grandson, Ethan. There are two important issues for over-winter success: food and hive ventilation. We make sure that the brood nest is located low in the hive with frames of capped honey above. To get this arrangement, we may need to move frames or rearrange hive bodies. It is the tendency of honey bees to move upward in the hive over the winter. The heat of the bees’ winter cluster warms the stored honey above the cluster; the bees eat this honey; and then they move up to occupy the empty cells. If the bees begin the winter with their brood nest located high in the hive, they may not move down to feed on available honey stores. It is frustrating for beekeepers to find honey bee colonies that starved while there is plenty of available honey stored inches away from the bees’ winter cluster. If the hive is light in weight when one end is lifted, the bees need feeding. For fall feeding, “heavy” syrup of two parts sugar to one part water is readily converted to honey and stored.

The second important issue in bee hive set-up for winter is ventilation. Bee hives are warm and damp on the inside. Cold winter temperatures outside the hives cause condensation to form on the inside hive walls. The effect is opposite that of a glass of iced tea on a hot, damp Delta summer day where condensation forms on the glasses’ outside surface. Water dripping in the hive can kill bees. A small vent at the top of the bee hive is all that is needed to remove hive moisture. Today’s photo shows a full box of capped honey above the brood nest.

--Richard

Superweeds and Superpests

The use of genetically modified crops was intended to reduce the need for herbicides to control weeds and insecticides to control pest insects. However, The New York Times reports that instead herbicide use increased over 16 years, while insecticide use decreased somewhat. The widespread use of a single herbicide glyphosate, sold under Monsanto’s brand name Roundup, has resulted in the evolution of a number of glyphosate-resistant weeds. The Times piece, http://green.blogs.nytimes.com/2012/10/05/the-legacy-of-pesticides-superweeds-and-superpests/?src=rechp, describes different approaches to the use of these genetically modified organisms. “Roundup Ready” corn, soybeans, and cotton seeds were planted on 1.37 billion acres from 1996 to 2011. The GMO plants, tolerant of the herbicide glyphosate, were supposed to reduce or eliminate the need to till fields and reduce the need for harsher chemicals. The use of these GMOs was supposed to also save money and be less stressful on the environment. As glyphosate-resistant weeds increased, increases in the use of glyphosate slowed; and in 2010 the National Research Council warned that, “Eventually, repeated use will render glyphosate ineffective.”

Those deploying the genetically modified seed containing the Bt gene producing toxins from the soil bacterium Bacillus thuringiensis recognized the potential for evolving resistant insects, and they took precautions. They required that a percentage of non-Bt seed be planted with Bt crops to ensure that some insects susceptible to the Bt toxin survive to mate with survivors of the Bt crops. Otherwise, surviving pest insect populations could become increasingly resistant to the Bt toxin with each generation. The mechanism for ecological harm from chemical pesticides was described by Rachel Carson in Silent Spring 50 years ago: “First, many of these chemicals are indiscriminate, killing not only pest but also the predators and parasites that help to keep them at bay. Second, surviving pest populations become increasingly resistant to the applied toxins with each generation, as those most susceptible to the toxins die off. It’s natural selection in overdrive.” Today’s photo: applying herbicide to control grasses in GMO soybeans.

--Richard

Transitions

Three types of bee hives are used in Ethiopia. Ninety-seven percent of the hives are traditional hives, long baskets built at no expense of cane and banana leaves. These hives are usually hung high in trees, but they are also attached to the outside walls of houses. Some traditional hives are placed inside houses under beds. Modern bee hives similar in design to the Langstroth bee hive comprise two percent of Ethiopia’s bees. The remaining one percent of Ethiopian bee hives is top bar hives, described as “transitional hives.” These simple boxes are also built from locally available materials at no expense. Transitional hives provide an economical method of managing honey bees that allows for the benefits of modern beekeeping: ease of hive inspection, ability to combine and divide colonies, move brood between hives, requeen, and improve genetics. Most importantly, transitional hives allow for the non-destructive harvesting of high quality honey. Beeswax is harvested by crushing honeycombs. Hive products are collected without killing or losing the honey bee colony. Today’s photo from Ethiopia shows one of Teshome’s transitional bee hives mounted in a tree. This top bar hive is covered in plastic and foliage as is the custom in Ethiopia. I recommended that Teshome consider removing the foliage to improve air circulation. Chalkbrood, a honey bee fungal infection, is a major hive problem in Ethiopia’s rainy season.

Many transitions are occurring on Ethiopian farms. Beekeepers earn additional income with transitional and modern bee hives. Using standardized sized hives, beekeepers can move combs from one hive to another. Teshome recognizes the benefits of improving queen bee genetics; he uses similar techniques in cattle breeding. He foresees the ability to produce gentler bees by selecting queen stock from his best hives. His farm is steadily transitioning to a broader based economy. Teshome eagerly traces the design of my hive tool so that he can have the local blacksmith produce tools for area beekeepers to take a more hands-on approach to beekeeping.

--Richard

Biological Controls

Before embarking on my latest beekeeping trip to Africa, I checked the hive that I was using to transfer a colony of feral honey bees from a hollow tree. All was progressing well, the capture hive was full of bees; the bees even filled two honey supers with summer honey. When I returned a few weeks later, the hive was completely “slimed” by small hive beetle larvae; the bees had abandoned the hive; and the honey was fermented. The hive was overtaken by small hive beetles. Bees and beekeepers find invasive small hive beetles difficult to control. Currently, chemical and cultural controls are used to reduce small hive beetle populations.

Researchers at the University of Arkansas asked a question: Could the small hive beetles have brought their own parasites with them when they entered the US? The presence of such a parasite of the small hive beetle could possibly lead to a biological control for these bee hive scavengers. To investigate the possibility that there may be a not-yet-discovered parasite, Natasha Wright collected small hive beetle adults and larvae and samples of soil from bee yards in Arkansas and adjacent states. She dissected 749 adult beetles and 230 larvae from 13 counties in Arkansas and one county each in Oklahoma and Missouri. Natasha found no microbial pathogens in the SHB larvae, but she did find a protozoan pathogen in adult SHBs from three Arkansas counties. Most of the infected beetles were from a single apiary in nearby St. Francis County, Arkansas. One infected beetle was found in a Peace Bee Farm apiary in Crittenden County, Arkansas. In total, 5.3 percent of the adult beetles sampled were infected with the protozoan pathogen, which forms cysts in the beetles’ Malpighian tubules. The heavily infected beetles detected in St. Francis County were described as having an “impaired function in life.” Hopefully, research will find safe and effective controls for small hive beetles. For published results: www.springerlink.com/content/b103041x41163216/. Today’s photo: SHB larvae slime a hive.

--Richard