APIS Volume 9, Number 2, February 1991
In this issue
- RBBS in California--Electronic Bee Bulletin Board
- More on Queen Quality
- Citrus Happenings and Nectar Production
- Comments on Blueberry Pollination
- Bee Attractants
BEE BULLETIN BOARD SYSTEM-RBBS IN CALIFORNIA
Wildbees BBS, a beekeeper-run computer bulletin board system (BBS) has been installed in California. The Operator (SYSOP), Mr. Andy Nachbaur, is trying to reach out to what he says are the "hundreds of beekeepers I know who have computers." The bulletin board is available 24 hours per day and transmits at 2400 baud. The phone number (209-826-8107) is for computer data only and requires a modem for access.
According to Mr. Nachbaur, here's what you can do right now:
- Leave messages for Bob Brandi, President of the American Beekeeping Federation.
- Leave messages for Jim Robertson, President of the California Beekeepers Association.
- Leave messages for anyone using the system.
- Retrieve LD-50 values for pesticides.
- Download several years' worth of newsletters and bulletins provided by Malcolm T. Sanford, Extension Apiculturist, University of Florida.
I am particularly proud of the last item. The Florida Extension Apiculture Program is a partner with a producer in this pioneering effort, an example of extension information being made available to a broader audience. I urge anybody with a yen to experiment and the proper equipment (computer, modem and communications software) to call up Wildbees BBS and tell them I sent you.
MORE ON QUEEN QUALITY
Last month's article on queen quality provoked several comments on this controversial subject. It was suggested that selecting only for number of ovarioles, spermatheca volume, number of spermatozoa and presence or absence of nosema was not necessarily good practice. That's because these characteristics cannot be correlated with behavior. For example, what the beekeeper cares about is how defensive or how productive the offspring of the queen (the colony) might be, not the number of her ovarioles. Although this is true, these characteristics are still important because they show that physiologically the queen will be able to produce the number of workers necessary to maintain a healthy colony. In addition, in the absence specific genetic information on selected queens, these measurements provide an allimportant yardstick to compare individual queens.
I mentioned last month that the New Zealanders were not ignoring the genetic aspects of quality queens. Neither are U.S. beekeepers; this was the general theme of the American Beekeeping Federation's recent convention in Mobile, AL. A queen breeding workshop was held to discuss how improved stock would help the beekeeping industry cope with the African honey bee. Three resolutions of the convention were adopted as a result:
1. WORKING for establishment and implementation of a program under which the U.S. Department of Agriculture or state departments of agriculture will certify queen rearing operations that demonstrate that such operations ensure adequate control of matings to produce gentle stock.
2. RECOMMENDING that importation of a particular honey bee stock be allowed if and only if that stock has an identifiable beneficial trait that has not been found in existing U.S. honey bee populations; that the dissemination of stock be allowed if and only if the stock has been quarantined and regularly examined for at least one year without detecting any disease or parasite of honey bees; and that the Federation be consulted prior to all proposed importations of honey bee stock.
3. SUPPORTING the concept of the establishment of a central honey bee stock center.
The last resolution arose as the result of a proposal by the Walter Rothenbuhler Honey Bee Research Facility at The Ohio State University. Sue Cobey and Tim Lawrence, now affiliated with that facility, discussed how a central honey bee stock center would help the industry. This would not be a free service, however, and only time will tell whether there will be significant financial commitment by beekeepers to support such a venture.
CITRUS HAPPENINGS AND NECTAR PRODUCTION
As the Ides of March approaches, beekeepers are readying their colonies for the annual pilgrimage to citrus groves. Many bemoan the fact that citrus honey production isn't like it was in the old days. To some that time period is far in the past, but to others it was just yesterday. Changes over the last decade have vastly changed citrus culture in Florida, affecting beekeepers in the bargain.
An article in the December, 1990 issue of Citrus and Vegetable Magazine specifically discusses the effect of freezes on the citrus industry. According to the author, threat of cold has created problems ever since the Spanish introduced the crop more than 500 years ago. The industry at the turn of the century was centered in Gainesville and Palatka. Freezes in 1894 and 1895 forced citrus southward, although production continued in Lake, Orange and Marion counties until freezes in the 1960s and the 1980s finally put most growers out of business.
Today, the article says, the northern growing area is above Interstate 4, with state road 70 marking the boundary between the central and southern region. In the northern region, dead trees are a common sight, and growers have only three options: replant, sell out or find alternative crops. Most choose the latter two. For those that stay in business and/or choose to replant, the article says, small, well-protected, specialty fruit will probably be the mainstay.
The "new" central citrus growing region has increased in acreage, the article continues; northern growers are moving south to avoid cold and southern growers are looking to expand. This area, however, can still suffer from cold temperatures. The 1989 freeze did a lot of damage, but a good deal of replanting will occur in the region. The central area will continue to produce most of the fresh fruit in the future.
Southern Florida is the last hope for commercial-scale freeze-free citrus production, and there are many high density plantings in the region, the article says. After the 1989 freeze, those that could no longer afford to plant in freeze-prone areas moved into this region. The southern area will continue to be the major area for process fruit.
Shifting citrus culture continues to affect beekeeping in many ways. There are different soil conditions in the coastal and southern flatwoods areas than in the more northern areas on the Florida ridge. Although few studies exist on the subject, many think the deep sand ridge soils produce better nectar quantity and quality than shallower soils nearer the coast. Applications of systemic toxic materials like aldicarb, though not a problem on the ridge, have been implicated in reducing honey bee field force through contaminated nectar from trees grown in the shallower soils of coastal areas. Citrus culture continues to feature new varieties and be characterized by high density plantings, especially in the south. Although many agree this affects nectar production, it is not known exactly to what extent. One reason for this is that it takes several seasons of experience to determine suitability of locations for nectar production.
Commercial pollination strategies should continue to be investigated in each area and customized based on the kind of fruit being produced. No grapefruit, for example, is being produced in either the north or central regions. Presently, most pollination done in citrus groves is provided free for the nectar received. However, there is information suggesting that certain specialty varieties require cross pollination. Thus, the opportunity for marketing pollination to growers exists.
In the future, it may be possible to convince citrus growers to remunerate for colonies because of their pollinating efforts, whether or not nectar is abundant. I know of at least one beekeeper who has successfully marketed pollination services in large groves in southern Florida. There is evidence that during times when beekeepers' movements are heavily regulated (such as citrus canker, tracheal and Varroa mite introductions in the 1980s) citrus managers were concerned about maintaining bee populations in the groves.
Introduction of the African bee may also bring new opportunities to beekeepers in citrus-producing areas. Numerous feral nests may be hazardous to workers in groves, resulting in a cry for beekeepers to consult on the problem. The use of poisoned bait stations and trap hive technology to remove wild bees could also be coupled with commercial pollination contracts to ensure adequate populations of bees in groves when they are most needed.
In the 1985 article "Symbiosis: The Florida Bee Industry-Citrus Connection," The Citrus Industry, Vol. 113, pp. 265-258, I wrote, "The citrusbeekeeping industry symbiosis, like most mutually beneficial relationships, is tenuous and constantly changing. Certainly, the citrus canker and freeze situations threaten to disrupt it. In addition, use of pesticides can also bear bitter fruit. The key to keeping the relationship harmonious is communication between persons involved. The beekeeper must empathize with the problems of the grove owner and vice versa." This may be even more relevant advice for beekeepers in the 1990s.
COMMENTS ON BLUEBERRY POLLINATION
I received interesting feedback on the blueberry pollination article published last month. Dr. Chris Plowright at the University of Ottawa writes: "Contrary to what you said in the newsletter, the technology DOES exist for mass-rearing bumble bee colonies in large quantities. The European company called Koppert now rears more than 10,000 colonies per year (for greenhouse pollination of tomatoes), and we ourselves ("Bees-under-Glass Pollination Services Inc.") expect to rear about 1,500 colonies this year and about 5,000 next year. The problem with this, however, is that bumble bee colonies are expensive to rear--the price varies between about $400- $600 per colony; and although it is highly likely that one good strong colony placed in the middle of a 100-acre blueberry field would, in a year of scarcity of wild bees, increase the value of the crop by more than $600, PROVING that to the satisfaction of the grower is pretty difficult." Dr. Philip Torchio of the Bee Biology and Systematics Lab, Logan, UT, was kind enough to send his thoughts on the subject. He says that blueberry pollination is not restricted to only bees that "buzz pollinate." The major problem of honey bees on rabbiteye blueberries is not inability to buzz flowers, but the flower's long corolla and narrow opening which make nectar collection difficult. This is also the reason both carpenter bees and bumble bees make slits in the corolla. Once slits are made, other species (including honey bees) use these openings only to collect nectar.
His work on highbush blueberries, Dr. Torchio says, has convinced him that only 250 nesting females per acre of the bee, Osmia ribifloris, is required to achieve maximum pollination potential. The large numbers of pollinators usually recommended, he says, are often referred to in honey bee terms ( so many colonies per acre). However, it is not true that twice as many colonies of honey bees will necessarily result in twice as many foragers. This is because foraging populations of most bees (including honey bees) tend to disperse until maximum numbers of foragers per unit space are established to collect resources at high efficiency rates.
Commercial blueberries (highbush, rabbiteye and lowbush), Dr. Torchio says, should be thought of as separate crops. Since it is obvious that honey bees are not the best pollinator of any blueberry species, he concludes, efforts to develop management strategies for alternative pollinators are needed. Dr. Plowright says: "...the best native bees to encourage are those species (such as Habropoda) which are SPECIALISTS on the crop. The main point here is that the activity period of such specialists coincides in time with the flowering of the crop." He concludes that what we should be doing is finding out how to manage appropriate parts of the landscape to build up nesting populations of these alternative pollinators.
In an effort to monitor the blueberry crop more closely this season, a working group headed by Dr. L.K. Jackson of the Fruit Crops Department at the University of Florida has been formed. Because so little is known about rabbiteye blueberry cultivation in Florida, the working group is developing a scouting card which is designed to obtain basic information on crop conditions throughout the growing season. Monitoring the number of honey bees, bumble bees and flowers with slits in fields over a period of years should provide valuable insight about blueberry pollination. If you wish to receive information on the activities of the group, contact Dr. Tim Crocker, Fruit Crops Department, Fifield Hall, Gainesville, FL 32611-0511, ph 904/392-1996.
BEE ATTRACTANTS
The idea of increasing pollination potential by applying substances attractive to honey bees has been around a while. Many substances [e.g. Bee Line (R)] are based on using sugar to attract the insects. However, these may also attract pests, as well as pollinating bees. The use of pheromones (odors) narrows the field by attracting only certain species. Honey bee pheromone attractants are now on the market which appear to have potential to increase bee pollination, however, hard evidence of their cost effectiveness is not yet available in all situations.
Recently, Dr. Dewey Caron and the University of Delware conducted an informal survey on the use of a product called Bee Scent (R), produced by Scentry, Inc. There is evidence that in Virginia and Georgia, the product has increased apple pollination as well as that on pears, plums, cherries, melons and cucumbers. According to Dr. Caron, Bee Scent (R) does have a role to play under some circumstances, although at about $25 per acre, another bee colony may be a better alternative. As reported by Dr. Caron, Dr. R.K. Fell in Virginia observed some increase in pollinating activity. Dr. Fell, however, said that caution in recommending Bee Scent (R) was in order. Bees should be the first priority and the attractant viewed as a way to direct bees to areas where pollinating activity is needed. The manufacturer of Bee Scent (R) has technical bulletins available on most of the fruits mentioned above.
The January, 1991 issue of Agrichemical Age reports on another honey bee pheromone-based attractant, Bee-Here (R), in an article entitled: "To Bee or Not to Bee." According to the article, past experiments with attractants have only been partially successful. Bee-Here (R), however, contains a stronger concentration of pheromones in a controlled-release formulation which remains stable and has a long shelf life. In a trial in a Texas peach orchard, the material was definitely responsible for increasing bee activity and fruit set. It also helped pollination of melons and cucumbers in both Texas and California.
The article quoted Dr. Al Knauf, technical development specialist for Fermone Corporation that markets Bee-Here (R) concerning variability of results: "...the material is going to work best under borderline conditions; that is, when conditions are not completely favorable to bee activity." When natural conditions are good for pollination, results will be minimal. As an example, according to the article, the conditions in the San Joaquin Valley were ideal for cucumber pollination last year (usually once in every seven seasons) and although Bee-Here (R) brought the bees to the crop, they did little pollination. According to Mr. Mike Turbetti, branch manager of Wilbur-Ellis, Stockton, CA, maybe the cucumbers didn't need pollination by bees, but Bee-Here (R) attracted them in any case.
Malcolm T. Sanford
Bldg 970, Box 110620
University of Florida
Gainesville, FL 32611-0620
Phone (904) 392-1801, Ext. 143 FAX: 904-392-0190
http://www.ifas.ufl.edu/~entweb/apis/apis.htm
INTERNET Address: MTS@GNV.IFAS.UFL.EDU
©1991 M.T. Sanford "All Rights Reserved
