APIS Volume 3, Number 4, April 1985
In this issue
- Frank Robinson Retires-- A Milestone
- Alternate Crops on Citrus Land
- Feeding Sugar to Bees--Feed Conversion Figures
FRANK ROBINSON RETIRES
It is with mixed emotions that I report the retirement last month of Frank Robinson, the University's research apiculturist. Frank joined the University of Florida faculty in 1950. During the subsequent thirty-five years, he has become known and respected nationally and internationally for his service to the apicultural community.
Frank is a long-time member of the Florida State Beekeepers Association and served as both president (two years) and secretary (ten years). He also held offices in the Entomological Society of America and consulted in a number of capacities concerning bees and pollinating insects. During his tenure, he wrote articles for the various bee journals and scientific publications and co-authored with E. Oertel, Chapter nine, "Sources of Nectar and Pollen," in The Hive and the Honey Bee, edited by Dadant and Sons.
In addition to the above activities, Frank has served many years on the Board of Directors and Executive Committee of the American Beekeeping Federation, as well as regional representative of the International Bee Research Association. Although he is retiring formally from the University, it is fortunate for the beekeeping community as a whole that Frank will stay active as Secretary-Treasurer of the American Beekeeping Federation. He has been and continues to be one of the prime movers in both international and national apicultural research program planning and development.
Frank will be missed by myself and others as an active participant in the University community. However, I'm sure he'll continue to be a source of support and inspiration for the University's apicultural program. I wish Frank and Sarah well on their collective retirement, it is well deserved. Personally and professionally though, I am grateful they'll both still be around to provide much needed counsel and strength during these times of great stress for the beekeeping industry.
ALTERNATE CROPS ON CITRUS LAND
Ever since the disastrous freezes of the last two years I have bee approached innumerable times about potential nectar-producing crops that might be planted on citrus land. Reasons for this might be several. One would be to keep land agriculturally zoned, for example, if citrus cannot or will not be replanted. Another might be simply in search of alternate crops which would be of value to the grower as well as the beekeeper.
Recent suggestions for alternate crops include a long list of clovers, spanish needle, and partridge pea. The latter two are interesting plants, but little information about their cultivation is available. Partridge pea at first glance appears ideal as a nectar-secreting legume. However, it apparently is one of the few in the family that does not fix nitrogen. Little is known about its cultivation, although some seed may be available from the Agricultural Stabilization and Conservation Service (ASCS). The crop appears to be of little economic value, except as a possible wildlife food.
Crops like citrus, which maximize both nectar production for bees and agricultural production are not easy to find. Conventional wisdom has always dictated that it is not economical to plant crops soley for nectar production. Sowing plants that are useful for other reasons, however, and that provide a good nectar crop as a bonus has always been a useful strategy. Perhaps the best types of Florida plants to examine which are suitable for bees and other uses are winter forage legumes, such as white clover, crimson clover, alfalfa, sweet clover, and red clover and summer forage legumes like alyceclover and hairy indigo.
White clover has traditionally been a good honey plant in south Florida, but its growth is dubious on the well drained lands of the central ridge. Crimson clover is a good cover crop and it is used with success on the roadsides in south and central Georgia and north Florida. However, it requires well-drained heavier soils, and blooms for a very short time period.
Plants used for livestock feed are usually cut prior to or just at bloom, when the nutritional content is at its maximum. This is particularly true of the alfalfas. In Florida, Alfalfa 77 is a quality forage and reports here at the University indicate good bee activity, but it usually is harvested right at bloom time. For more information on the plant, consult IFAS Circular S-271, "Florida 77 Alfalfa and Recommended Management Practices for its Production, by E.S. Horner and O.C. Ruelke. A better crop might be alyceclover, however, informal reports indicate very little bee activity; it is a self-pollinator and can be damaged severely by rootknot nematodes. Of the clovers, sweet clover may be best, because it blooms over a longer period of time than most and has a large "flush" of bloom, the reason it is such an outstanding nectar plant in the midwest. Two varieties recommended are Hubam and Floreana.
Hairy indigo appears to be an excellent plant as well. Indigofera hirsuta L.) is a native of tropical Africa and Asia." It resists root-knot nematode, produces seed, and is one of the a few annual warm-season legumes suited to Florida conditions. Farmers appear to have differing opinions on the plant. Some see it as a weed. Others use it as green manure, hay silage or for direct grazing. It requires little care or capital input with a relatively high return of quality forage and eventual gains in animal weight. Many producers use the plant to achieve a natural, annual reseeding stand on dry, infertile, deep sandy soils.
Informal reports indicate bees visit hairy indigo, however, no complete studies of its nectar secreting abilities are available. It certainly appears to be worth a try, considering its value as a livestock forage crop. Details on all recommended legumes for Florida are found in Florida Cooperative Extension Service Agronomy Facts Numbers 146 and 166. These guides include short descriptions of all recommended legumes and advise on inoculation of seed, planting, liming, fertilizing, irrigating and managing the crop for livestock. All of the above publications should be available from your local county agent.
FEEDING SUGAR
A.G. Matheson is an Apicultural Advisory Officer in New Zealand and writes a publication, The Beekeepers' Bulletin. In February 1985, he published some interesting information on feeding sugar. The three tables below show calculations to determine the relationship between the amount of sugar fed a colony, its dilution in water and resultant weight in stores:
A. Weight of sugar used to produce a particular volume of syrup, and the weight of stored food produced. W=water added (kilograms); Sy=syrup volume (liters); St=stored food (kilograms)
Sugar Sugar/Water Ratio
weight 1:1 1.5:1 2:1
in
kilograms W Sy St W Sy St W Sy St
1.0 1.0 1.6 1.0 0.67 1.27 1.12 0.5 1.1 1.2B. Volume of syrup resulting from various proportions of sugar and water, and the weight of stored food produced. S=weight of sugar (kilograms); W=water added (liters); St=stored food (kilograms).
Volume Sugar/Water Ratio
of syrup 1:1 1.5:1 2:1
in
liters S W St S W St S W St
1.0 0.62 0.62 0.62 0.79 0.53 0.90 0.91 0.45 1.09C. Amount of stored food obtained by feeding syrup containing various proportions of sugar and water. S=weight of sugar (kilograms); W=water added (liters); Sy=syrup volume (liters).
Stored Sugar/Water Ratio
food 1:1 1.5:1 2:1
in
Kilograms S W Sy S W Sy S W Sy
1.0 1.0 1.0 1.6 0.89 0.59 1.13 0.84 0.42 0.92The following examples reveal use of the tables above:
1. How much syrup is required to bring a colony having only 3 kg of stores up to 10 kg? Table C shows that 6.5 liters of 2:1 syrup are required. This is approximately equivalent to 7 kg (difference between 10 and 3) multiplied times 0.92 (amount of syrup of a 2:1 sugar/water ratio that produces one kilogram stored food). Feeding 1:1 syrup requires almost double the volume (7 X 1.6 or 11.2 liters).
2. If you feed four liters of syrup to a colony, how much resulting stores can you expect? From table B, the following figures are easy to calculate:
2.5 kilograms of 1:1 syrup (4 X 0.62)
3.6 kilograms of 1.5:1 syrup (4 X 0.90)
4.4 kilograms of 2:2 syrup (4 X 1.09)3. Feeding a metric ton (1000 kilograms) of sugar in 2:1 syrup, will result in how much stored food? From Table A, the answer is 1200 kilograms (1000 X 1.2).
Note: one kilogram = 2.2 pounds and one liter = .26 gallons
Source: Imkerliche Fachkunde, 3rd edition, 1975. Translated by E. Jaycox.
Sincerely,
Malcolm T. Sanford
Bldg 970, Box 110620
University of Florida
Gainesville, FL 32611-0620
Phone (352) 392-1801, Ext. 143 FAX: (352)-392-0190
http://www.ifas.ufl.edu/~entweb/apis/apis.htm
INTERNET Address: MTS@GNV.IFAS.UFL.EDU
©1985 M.T. Sanford "All Rights Reserved
