 |
| Figure 1. Map and Soil type of the study area (Debre-Nazret) |
| Livestock Research for Rural Development 28 (7) 2016 | Guide for preparation of papers | LRRD Newsletter | Citation of this paper |
The study was conducted in Debre-Nazret and Hayelom kebelles of Tigray region from August 27, 2012 to March 30, 2015. It was aimed at identifying and documenting major honeybee flora with their flowering calendars. Data were collected from 130 beekeepers and experienced households of the study kebelles. To identify the honey bee flora plants used as bees forage, 40 quadrates were established in wet season and repeated in dry season in different land use systems. Drought was major constraint on beekeeping development in the areas.
The results showed that a total of 44 bee plant species belonging to 30 families were identified. The most important bee flora species included Leucas abyssinica, Hypoestes forskaolii, Becium grandiflorum and Eucalyptus camaldulensis. The abundance of honey bee flora in closed forest of the wet and dry seasons in the Debre-Nazret kebelle was 7731 and 2942 respectively. Enclosure area was good source of honey bee flora with diversified important bees forage than the other land use systems. Generally, Debre-Nazret and Hayelom are rich in diversity of bee flora for the existing honey beekeeping practices, so conserving and propagating of drought resistant honey bee flora species for the sustainability of the practices in the areas is needed. Hence, effort should be made in conserving and managing bee flora of the areas
Keywords: Becium grandiflorum, Debre-Nazret kebelle, Eucalyptus camaldulensis, Hayelom kebelle, Hypoestes forskaolii, Leucas abyssinica
Production of honey and other products of honey bees depend on availability of floral resources (bee forage) and is a very important field for honey beekeepers (Amsalu et al 2003). Most of the methods of obtaining information about plants used in an area are based on direct field observations of foraging honeybees. Nectar as sources of honey provides heat and energy for honey bees and pollen provides protein, vitamins, fatty substances, and other nutrients (Amsalu et al 2003). Adequate nectar and pollen resources are critical in maintaining honey bee health (Michener 2007). A deficiency in quantity and quality of pollen and nectar can lead to demographic decrease of bee colonies leading to low colony populations, which collect pollen and nectar (Keller et al 2005).The role of nutrients is so critical that the beekeeper often must provide supplements as sugar syrup or pollen supplement to prevent nutritional deficiency and colony failure (Alaux et al 2010).
Currently, more than 6000 species of flowering plants are estimated to be found in Ethiopia, of which most of them are honeybee plants (Girma 1998). Due to this potential availability of diversified bee flora and other environmental factors, Ethiopia has the highest bee density and is the largest honey producer in Africa. In Ethiopia, beekeeping is one of the oldest agricultural practices that passed from generation of generation without modification up to the present time (Fitchl and Admasu 1994).The diversified flowering plants in Ethiopia and their blooming season greatly vary from place to place; this enables the country to sustain many of the honeybee colonies (Admasu 1996). About 500 important honeybees plant species identified by Fitchl and Admasu 1994 are important for bee plants. For example species such as: Eucalyptus camaldulensis and Olea europeae are some of the tree species that are source of both pollen and nectar. Leucas abyssinica, Becium grandiflorum and Carissa spinarum are good source of pollen and nectar.
Tigray region is one of the centers of early civilization as well as beekeeping practice in Ethiopia (Ayalew 2004). Beekeeping practices in the region is as old as farming and it has been traditionally practiced for a long period of time (Meaza 2010). The progress of changing the traditional practice is slow and the entire numbers of honeybee colonies are managed in a traditional way (Fichtl and Admassu 1994). Most of the honey coming from Tigray is the white, and is the best and highly demanded in both domestic and international markets for years (MoARD 2010).The number of bee hive colonies of Tigray was estimated to be 206,040 (37% and 63 % of which are modern and traditional bee hives, respectively) (MoARD 2010). Though, beekeeping practice in recent years is improving, the contribution to honey production of the region to national honey production is still small (around 5%) due to higher degradation of natural resource and/or degradation of honeybee flora that affect the diversity of honeybee forage plants (Girma 1998; Gidey and Mekonen 2010 and Melaku et al 2008).
In Tigray region, about 65 plant species were identified as potential, mid potential and low potential to foraging bees and to beekeeping intervention (Ayalew 2006). Identifying the existing honeybee plant resources may help to assess the productivity, adaptability, and swarming, absconding and other basic behaviors of the regional bee resource (Ayalew 2006). Natural vegetation in general and forest plants in particular that cover the lands in Tigray have been cut down leaving no remnants that help to reinstate (Ayalew 2006). The loss of these natural plants species, has undoubtedly affected the life pattern and productivity of honeybees of the region. Bees are essential parts of the agricultural system. Although the value of honeybees in crop pollination is under estimated, it has a significant role in increasing national food production and regeneration of plant species. Honeybees are the prime pollinating agents in the world. Their service in pollination is estimated to be worth over 15 times the value of all hive products together, although it is much more difficult to quantify their benefit (EARO 2002). Hackett 2004 estimated the value of honeybee pollination to U.S. agriculture to be $14 billion annually. Honeybee is also believed to play a significant role in the economy of Ethiopia through pollination services. Pollination is one of the most important factors that influence seed production of agricultural crops. In Ethiopia, an experiment was conducted to determine the consequence of pollination on Niger (Guizotia abyssinica) and the result showed that honeybee increased the seed yield of Niger by about 43% (Admasu and Nuru 2002) and Onion (Allium cepa) by two fold (Admasu et al 2008).
The concepts of sustainability are seen as the guiding principle of economic and social development, typically with reference to biological resources (Zemede 2001). Generally, conservation of threatened plants is achieved through in-situ (conservation on their natural habitats like natural reserves and parks) and ex-situ (conservation in field gene banks, seed banks and botanical gardens) (Cunningham 1996). Both in-situ and ex-situ conservation efforts are implemented complementarily to capture plant genetic resources and the traditional practices associated with them (Fisseha 2007). Many landscapes, which once contained rich stands of important honey bee flora plants is found to contain only relics of these remarkable species. This is due to uprooting the plants from the ground for its medicinal, fuel wood and other traditional values. Other factors for decline in density could be increased livestock populations and natural resource degradation. For example natural regeneration of Becium grandiflorum from seed is being restricted by widespread human interference (uprooting the plant for fuel wood and medicinal values) and there are no new plantations and the result is shortage of bee forages in the Tigray region (Haftom and Yaynishet 2012). Plants are the food source of honeybees. According to study conducted in Zaria, northern Nigeria, about 57.1% of the bee visited plants are perennials while 42.9 % are annuals. Sanford 2003 noted that many plants produce pollen for the bees, but it is usually the nectar producing species that are the most interesting for beekeepers. In planning a bee pasture, it is important to choose a collection of plants that will produce unbroken succession of blooming throughout the season (Delaplane et al 2010). One way is to improve bee nutrition (ultimately, increasing their populations) by planting or encouraging more-or-less permanent bee pasture near the crop of interest, such as trees, bushes and woody perennials.
Floral calendar for honey beekeeping is a time table for a beekeeper; the approximate date and duration of the blossoming periods of the important honey and pollen plants (Diver 2002). The common flowering time of Leucas abyssinica, Trifolium spp. and Becium grandiflorum is from August to September, whereas Hypoestes forskaolii and Bidens spp. commonly flower from September to October and August to October, respectively (Bista and Shvakoti 2001). Though an area could be endowed with bees forage, attention must be given to maintain the existing bee flora and multiplication of multipurpose plant species to make it sustainable (Bista and Shivakoti 2001). Jacobs et al 2006 noted that it is important to study the carrying capacity of an area up to a radius of 3km around the apiary, which can be foraged by bees within one flight. As showed in the Comprehensive Bees and Beeswax Marketing Plan 2nd drafts document (MoA 2003), Ethiopia has set a long-term plan to raise the current 43,373 tons of honey yield to a level of 149,056 tons annually. It was also planned to export 80% of the total honey production (MOA 2003).
The colony strength as well as honeybee products mostly depend on the availability and type of bee flora next to level of colony management practice (Bista and Shivakoti 2001). Apiary sites should be nearby the good bee forage plants to obtain good honeybee products and colony strength (Jacobs et al 2006).
A study in Ibadan (south west of Nigeria) by Mbah and Amao (2004) showed that the main nectar flow is from July to February, with a peak in January when the largest forest trees are in flower. As a result, at this time there is enough nectar flow and the colony is strong with surplus honey to harvest. Other studies by Bista and Shivakoti (2001) at Kabre, Dolakha district (Nepal) also showed that the peak periods of honeybee foraging activity and abundant bee floral plants were recorded during mid-February and May (spring season); whereas from mid November to February (winter season) is dearth period and the colony strength can be weak with little or no honey production. Large numbers of natural resources in Ethiopia are degraded and deteriorating due to over utilization and inefficient use of natural resources, especially the forest resource (Bedru et al 2006). This deforestation as well as reduction in vegetation covers has negatively affected the biodiversity of honeybees and/or bee flora plants. According to the study conducted in Burie District of Amhara Region by Tessega (2009), bee keepers try to overcome the problem of reduction of honey bee plants by growing different local bees forage plants nearby the apiary site. Despite these local efforts, the national beekeeping resource base is deteriorating at a faster rate warranting sustainable intervention progress (Melaku et al 2008).
This research is one step to achieve this goal and could contribute to the selection of the most important bee forage and their protection methods. In this regard, abundance and diversity of the honey bee flora and the quality/quantity of honey produced was studied at Debre-Nazret and Hayelom kebelles. Therefore, the general objective of this study was to investigate the honey bee forages diversity and honey production status in Debre-Nazret and Hayelom kebelles of the Tigray region. The specific objectives of the study were to: 1. assess abundance and diversity of honey bee flora 2. Identify the best honey bee flora 3. Document the blooming period of the honey bee flora of the study kebelles 4. Correlate honey production with seasons and 5. Identify major constraints of honey bee keeping in the study areas.
Debre-Nazret is part of the south eastern zone of Tigray about 27 kms west of Mekelle, capital of Tigray Regional state. It is situated between 13 0 26'Ns - 130 30'N latitude and 390 16' - 390 20'E longitude at an altitudinal range of 1508 to 2160 meter above sea level. According to the Ministry of Agriculture and Rural Developmnet and Bureau of Finace and Economic Developmnet of Tigray Region (2012) , the soil types of the study area comprise dystric gleysols (0.63%), dystric nitisols ( 90.84 %) eutric fluvisol (0.81 %) and leptosols(7.72 %) (Fig. 1).
|
| Figure 1. Map and Soil type of the study area (Debre-Nazret) |
The average temperature of the area ranges from 16.3 to 17.2 0C and the mean rainfall of the area ranges between 31.5 and 80 mm (Fig.2).
 |
| Figure 2. Mean annual Temperature and Rainfall
of Debre-Nazret
Source: National Meteorological Services Agency (2012) |
|
Table 1. Land use of Debre-Nazret |
||||||||||||
|
Peasant |
Agricultural |
Natural |
Rehabilitated |
Pasture |
Unfarmed |
Total |
||||||
|
ha |
% |
ha |
% |
ha |
% |
ha |
% |
ha |
% |
ha |
% |
|
|
Mshlam |
557(17) |
32 |
2000(60) |
41 |
150(5) |
19 |
400(12) |
24 |
200(6) |
6 |
3307 |
100 |
|
Kolal |
237(6) |
13 |
2090(55) |
43 |
98(3) |
12 |
295(8) |
17 |
1045(28) |
31 |
3765 |
100 |
|
Tegoga |
492(21) |
28 |
600(26) |
12 |
250(11) |
31 |
658(29) |
39 |
300(13) |
9 |
2300 |
100 |
|
Meami Atal |
484(15) |
27 |
170(5) |
4 |
300(10) |
38 |
332(11) |
20 |
1848(59) |
54 |
3133 |
100 |
|
Total |
1770 |
100 |
4860 |
100 |
798 |
100 |
1685 |
100 |
3392 |
100 |
12505 |
|
Land use of Debre-Nazret is indicated in table 1.Most of the Debre-Nazret kebelle together with the mountainous areas is covered with vegetation consisting of trees, bushes, shrubs and herbs (in the rainy season). The area is adjoined by Giba river. According to the Degua Tembien district report the area is honey bee potential and there are around 375 honey bee colonies. Two hundred twenty of the honey bee colonies is modern and the remaining 155 are traditional. There are around 210 honey beekeeper households in the study kebelle. Wheat, Barely, Teff, Sorgum and other leguminous cereal are the dominant crops in the study site.
The second site ,Hayelom, is located around 50 kms to the North eastern part of Mekelle in Atsbi wemberta district (Fig. 3).The area is located at an elevation of 1800-2400 meter above sea level.According to the Ministry of Agriculture and Rural Developmnet and Bureau of Finace and Economic Developmnet of Tigray Region , the soil types of Hayelom kebelle are chromic nitisols (40.2%), dystric nitisols (38.3%) eutric cambisol (20.4%) and leptosol(1.1%) (Fig. 3).
 |
| Figure 3. Map and Soil type of Hayelom
kebelle Note: ha = hectare,The numbers in brackets show percentage of each Peasant association |
Annual rain fall and temperature of Hayelom kebelle
According to the National Meteorological services Agency of Tigray region actual rain fall value of Hayelem kebelle for the last three years record ranges from 0 to 532.1 mm. Annual temperature ranges from 14.8 to 19.2 0C (Fig.4).
 |
| Figure 4. Mean annual rainfall and temperature
of Hayelom kebelle Source: National Meteorological Services Agency, Tigray branch (2012/13) |
Most of the Hayelom kebelle including the steep mountainous areas is covered with trees, bushes and shrubs.
|
Table 2. Land use of Hayelom |
||
|
Land use |
Area Coverage |
|
|
ha |
% |
|
|
Agricultural land |
956 |
16 |
|
Grazing land |
126 |
2 |
|
Natural forest |
3725 |
64 |
|
Rehabilitated land |
1056 |
18 |
|
Total |
5863 |
100 |
The the study sites were selected purposely. The picture showed in figure 5 is taken during the preliminary survey. The information about extension workers and the picture showed in the figure convinced the researcher to select the study sites purposely.
 |
 |
| Figure 5. Honey bee colonies in hives of Debre-Nazret (A) and Hayelom (B). Photo snapped by Gebru Equar in August 2012 |
|
The primary data were collected using semi-structured questionnaire, formal and informal discussion with groups, household interview and key informants. Likewise, direct observations were used. A Participatory Rural Appraisal (PRA) was used to generate information about rapid survey.
|
Table 3. Total Number of selected respondents |
|||
|
Selected |
Sampling Peasant |
Number of |
% |
|
Debre-
|
Meami Atal |
23 |
17.7 |
|
Kolal |
10 |
7.4 |
|
|
Mshlam |
12 |
9.4 |
|
|
Tegoga |
20 |
15.4 |
|
|
Hayelom |
Damayno |
16 |
12.3 |
|
Geter |
19 |
15 |
|
|
Haykimeshal |
10 |
7.4 |
|
|
Gergera |
20 |
15.4 |
|
|
Total |
130 |
100 |
|
To estimate honey bee flora composition and diversity in the study areas, samples have been collected from each land use (irrigated land, closed forest area, pasture land and backyard) and in two seasons of the main dry season “Bega” (end of December to mid-March) and main rain season “Kiremt” (end of June to mid of September). The size of quadrate in the closed forest was 400m2 (20m*20m), and 100m2 (10m*10m) was used for backyard, pasture and irrigated land.
Number of sample plots laid in all transect lines were 22, 5, 6 and 7 in closed forest , backyard , irrigated land and in pasture land, respectively .Therefore the total number of quadrates used for the study was 40 in both wet and dry seasons.
The abundance of honey bee plant species is defined here as the total number of all individual species in all forty quadrates in wet and dry season for each land use. The relative frequency of each bee flora species was calculated by determining the proportion of quadrates in which that species were encountered.
 |
To compare bee flora species composition of different land use systems and season, species richness, Shannon diversity index, and Shannon evenness index were calculated. Sum of species encountered with the plots of each land uses system in both wets and dry season was used to determine the species richness. Shannon diversity (H') and evenness (E') indices are also calculated as a measure to incorporate both species richness and species evenness or measure of heterogeneity (Shannon 1948).
 |
Where Hʹ= species diversity index
nl = natural logarithm
 |
 |
Equitability (evenness) is calculated to estimate the homogeneous distribution of bee flora species on the plot or the relative abundance. H' is high when the relative abundance of the different species in the sample are even, and decreases when few species are more abundant than the others or measures species or less heterogeneity. H'max is also the maximum level of diversity possible within a given population. To calculate diversity of the bee flora, past software was used to solve the Shannon diversity index equation (Shannon 1948).
Preference ranking was used to select the best honey bees forage types in the study kebelles. Preference ranking was performed using seven selected key informants for most important bee forage plants first on the basis of number of flowers per plant and secondly on the bases of the degree of attractiveness to honey bees. Accordingly, ten bee forage plants were chosen to be ranked preferentially by the selected key informants on the bases of flower number per branch as well as per plant giving the highest value (i.e. 10) for best plant for bee forage, second highest value (i.e. 9) for the second best plants and the least value (i.e. 1) for plants with relatively low use for bee forage as compared to other plants (Martin 1995).
Excel word 2010 and SPSS 17 (SPSS Inc. Chicago, USA 2008) were used and presented in the form of table. Moreover Past, species diversity analyzer was used to analyze Shannon diversity index (H`), species evenness (E) and species richness (Shannon 1948).
Honey bee flora plants used by the local community of the study areas were collected with adjacent to field walk interview and direct field observation with informants from August 27, 2012 to March 30, 2015. Representative specimens possessing both reproductive and vegetative parts were collected to make the identification easier. However, all documented honey bee flora were not collected and pressed because the study season was not the right time for some honey bee flora plants to bloom and lack of transportation (road was not constructed). Therefore, only available plants were collected, pressed and dried for identification while unavailable ones were just documented.
Identification of Voucher specimens was done on the field while collecting and processing them (Figure 6).Then, these plants were identified using previously done research works and using taxonomic keys in Books of 'Flora of Ethiopia and Eritrea' (Edwards et al 1995) and Honey bee flora of Ethiopia (Fichtl and Admasu 1994) in cooperation with Biologists/Taxonomists.
 |
| Figure 6. Honey bee flora identification and processing in the field |
The abundance of honey bee flora in Debre-Nazret and Hayelom was estimated during the field survey. The survey result showed that in the wet season total number of honey bee flora was higher in closed forest area followed by pasture and irrigated land in both study sites. Similarly, in backyard, relatively lower abundance bee forage was observed in both study areas. Conversely in dry season the abundance of bee flora in Backyards (Table 4 and 5) and irrigation cultivated land in Hayelom site (Table 5) were relatively higher than wet season. In closed forest area Hypoestes forskaolii, Becium grandiflorum and Bidens spp be highly abundant and most frequently available bee flora in the wet season (Table 4 and 5). The results showed that the abundance of bees forages in the dry season in all the land use systems except in irrigated lands decreased. The reason for the decrement of bee flora was because there was no rainfall in the dry season. In the wet season more abundant bee flora plants were available, while in the dry season only Cynadon doctylon (in closed forest area), Opuntia ficus-indica (in backyard), Cynadon doctylon and Argemone mexicana (pasture land), and Cynadon doctylon (in irrigated) were abundant (Table 4).
The abundance of bee flora in closed forest in the wet and dry seasons in the Debre-Nazret kebelle was 7731 and 2942 respectively. The reason for higher number of bee flora in the wet season is the rain. The abundance of bees forages for wet and dry seasons in Hayelom kebelle was 4144 and 624, respectively. The number of individual bee flora in closed forest in the wet season was 7731 and 4144 of Debre-Nazret and Hayelom kebelles respectively.
|
Table 4. Abundance (AB) and relative frequency (RFR) of bee flora species in Debre-Nazret |
||||||||
|
Species Name |
SS |
NPFO |
Wet Season |
NSFO |
Dry Season |
Land use |
||
|
AB |
RFR |
AB |
RFR |
|||||
|
Acacia origena |
22 |
10 |
11 |
45 |
7 |
10 |
32 |
Closed area |
|
Achyranthes aspera |
22 |
18 |
30 |
82 |
11 |
12 |
50 |
|
|
Agave sisalana |
22 |
4 |
4 |
18 |
8 |
9 |
36 |
|
|
Aloe berhana |
22 |
9 |
112 |
41 |
8 |
112 |
36 |
|
|
Azadirachta indica |
22 |
10 |
19 |
45 |
4 |
23 |
18 |
|
|
Carduus nyassanus |
22 |
16 |
42 |
73 |
11 |
30 |
50 |
|
|
Carissa spinarum |
22 |
22 |
114 |
100 |
22 |
114 |
100 |
|
|
Cordia africana |
22 |
7 |
23 |
32 |
7 |
23 |
32 |
|
|
Croton macrostachys |
22 |
17 |
120 |
77 |
17 |
125 |
77 |
|
|
Cynadon doctylon |
22 |
17 |
1200 |
77 |
11 |
555 |
50 |
|
|
Dodonaea angustifolia |
22 |
21 |
355 |
95 |
21 |
355 |
95 |
|
|
Eucalyptus camaldulensis |
22 |
3 |
93 |
14 |
3 |
93 |
14 |
|
|
Euclea schimperi |
22 |
22 |
323 |
100 |
22 |
323 |
100 |
|
|
Ficus vasta |
22 |
9 |
27 |
41 |
9 |
27 |
41 |
|
|
Heliotropium cinerascens |
22 |
9 |
112 |
41 |
7 |
30 |
32 |
|
|
Leucas abyssinica |
22 |
19 |
2080 |
86 |
0 |
0 |
0 |
|
|
Mangifera indica |
22 |
21 |
120 |
95 |
21 |
123 |
95 |
|
|
Ocimum basilicum |
22 |
7 |
1004 |
32 |
0 |
0 |
0 |
|
|
Olea europaea |
22 |
22 |
427 |
100 |
22 |
427 |
100 |
|
|
Otostegia integrifolia |
22 |
9 |
53 |
41 |
9 |
53 |
41 |
|
|
Prunus persica |
22 |
8 |
95 |
36 |
8 |
95 |
36 |
|
|
Polyscias fulva |
22 |
7 |
59 |
32 |
7 |
59 |
32 |
|
|
Satureja simensis |
22 |
4 |
19 |
18 |
4 |
19 |
18 |
|
|
Schinus molle |
22 |
7 |
37 |
32 |
7 |
37 |
32 |
|
|
Solanum incanum |
22 |
7 |
35 |
32 |
7 |
35 |
32 |
|
|
Solanum tuberosum |
22 |
6 |
31 |
27 |
6 |
18 |
27 |
|
|
Croton macrostachys |
22 |
10 |
18 |
45 |
10 |
18 |
45 |
|
|
Bidens spp |
22 |
20 |
951 |
91 |
0 |
0 |
0 |
|
|
Cordia sinensis |
22 |
9 |
150 |
41 |
9 |
150 |
41 |
|
|
Buddeja polysthya |
22 |
17 |
67 |
77 |
17 |
67 |
77 |
|
|
Total |
|
367 |
7731 |
1666 |
295 |
2942 |
1339 |
|
|
Acacia origena |
5 |
1 |
4 |
20 |
4 |
4 |
80 |
Backyard |
|
Achyranthes aspera |
5 |
2 |
5 |
40 |
2 |
4 |
40 |
|
|
Agave sisalana |
5 |
2 |
9 |
40 |
2 |
9 |
40 |
|
|
Aloe berhana |
5 |
3 |
12 |
60 |
3 |
12 |
60 |
|
|
Cordia africana |
5 |
1 |
1 |
20 |
1 |
1 |
20 |
|
|
Croton macrostachys |
5 |
3 |
5 |
60 |
3 |
5 |
60 |
|
|
Euphorbium candelabrum |
5 |
2 |
4 |
40 |
2 |
4 |
40 |
|
|
Ocimum basilicum |
5 |
2 |
3 |
40 |
2 |
3 |
40 |
|
|
Piliostigma thonningii |
5 |
3 |
50 |
60 |
3 |
50 |
60 |
|
|
Total |
19 |
93 |
380 |
22 |
92 |
440 |
||
|
Acacia origena |
6 |
2 |
10 |
33 |
2 |
10 |
33 |
Irrigated land |
|
Argemone Mexicana |
6 |
0 |
0 |
0 |
2 |
20 |
33 |
|
|
Carduus nyassanus |
6 |
2 |
13 |
33 |
2 |
13 |
33 |
|
|
Cynadon doctylon |
6 |
5 |
3100 |
83 |
4 |
560 |
67 |
|
|
Parkinsonia aculeata |
6 |
1 |
6 |
17 |
1 |
6 |
17 |
|
|
Total |
10 |
3129 |
166 |
11 |
609 |
183 |
||
|
Acacia origena |
7 |
3 |
3 |
43 |
3 |
3 |
43 |
Pasture land |
|
Leucaena leucocephala |
7 |
3 |
15 |
43 |
3 |
3 |
43 |
|
|
Musa X paradisiaca |
7 |
2 |
4 |
29 |
2 |
2 |
29 |
|
|
Ocimum lamiifolium |
7 |
1 |
3 |
14 |
1 |
3 |
14 |
|
|
Ricinus communis |
7 |
1 |
6 |
14 |
1 |
6 |
14 |
|
|
Rumex nervosus |
7 |
1 |
8 |
14 |
1 |
8 |
14 |
|
|
Trigonela foenum-graecum |
7 |
0 |
0 |
0 |
2 |
230 |
29 |
|
|
Zea mays |
7 |
2 |
1700 |
43 |
0 |
0 |
0 |
|
|
Capsicum annum |
7 |
2 |
50 |
29 |
4 |
95 |
57 |
|
|
Total |
15 |
1789 |
229 |
17 |
350 |
243 |
||
|
Note: NPFO = Number of plots in which bee flora occurred, SS = Sample size |
||||||||
|
Table 5. Abundance (AB) and relative frequency (RFR) of honey bee flora species in Hayelom |
||||||||
|
Species Name |
SS |
NPFO |
Wet Season |
NSFO |
Dry Season |
Land use |
||
|
AB |
RFR |
AB |
RFR |
|||||
|
Acacia origena |
22 |
4 |
10 |
18 |
4 |
10 |
18 |
Closed area |
|
Achyranthes aspera |
22 |
7 |
25 |
32 |
7 |
17 |
32 |
|
|
Aloe berhana |
22 |
7 |
121 |
33 |
7 |
121 |
32 |
|
|
Becium grandiflorum |
22 |
21 |
921 |
95 |
17 |
211 |
77 |
|
|
Carissa spinarum |
22 |
7 |
26 |
32 |
7 |
26 |
32 |
|
|
Cordia africana |
22 |
5 |
6 |
23 |
5 |
6 |
23 |
|
|
Croton macrostachys |
22 |
2 |
6 |
9 |
2 |
6 |
9 |
|
|
Dodonaea angustifolia |
22 |
7 |
89 |
32 |
7 |
89 |
32 |
|
|
Eucalyptus camaldulensis |
22 |
4 |
15 |
18 |
4 |
15 |
18 |
|
|
Eulea schimperi |
22 |
5 |
27 |
23 |
5 |
27 |
23 |
|
|
Leucas abyssinica |
22 |
18 |
2205 |
82 |
0 |
0 |
0 |
|
|
Mangifera indica |
22 |
20 |
108 |
91 |
20 |
57 |
91 |
|
|
Olea europaea |
22 |
11 |
19 |
50 |
11 |
19 |
50 |
|
|
Optica cylinderica |
22 |
4 |
112 |
18 |
0 |
0 |
0 |
|
|
Rhamnus prinoides |
22 |
2 |
2 |
9 |
2 |
2 |
9 |
|
|
Solanum incanum |
22 |
4 |
21 |
18 |
4 |
18 |
18 |
|
|
Bidens spp |
22 |
9 |
431 |
41 |
0 |
0 |
0 |
|
|
Total |
137 |
4144 |
624 |
102 |
624 |
464 |
||
|
Becium grandiflorum |
5 |
2 |
9 |
40 |
0 |
0 |
0 |
Backyard |
|
Cordia africana |
5 |
1 |
2 |
20 |
1 |
2 |
20 |
|
|
Ficus vasta |
5 |
3 |
18 |
60 |
3 |
18 |
60 |
|
|
Ocimum lamiifolium |
5 |
2 |
4 |
40 |
2 |
4 |
40 |
|
|
Opuntia ficus-indica |
5 |
1 |
5 |
20 |
1 |
5 |
20 |
|
|
Piliostigma thonningii |
5 |
2 |
23 |
40 |
2 |
23 |
40 |
|
|
Psidium guajava |
5 |
1 |
1 |
20 |
1 |
1 |
20 |
|
|
Satureja simensis |
5 |
2 |
6 |
40 |
20 |
6 |
40 |
|
|
Schefflera abyssinica |
5 |
2 |
13 |
40 |
2 |
15 |
40 |
|
|
Total |
16 |
81 |
320 |
32 |
74 |
280 |
||
|
Acacia origena |
6 |
1 |
2 |
17 |
1 |
2 |
17 |
Irrigated land |
|
Achyranthes aspera |
6 |
2 |
12 |
33 |
2 |
7 |
33 |
|
|
Cynadon doctylon |
6 |
5 |
3020 |
100 |
5 |
1200 |
100 |
|
|
Sida schimperriana |
6 |
0 |
0 |
0 |
2 |
18 |
33 |
|
|
Solanum tuberosum |
6 |
1 |
9 |
17 |
1 |
10 |
17 |
|
|
Parkinsonia aculeata |
6 |
1 |
6 |
17 |
1 |
6 |
17 |
|
|
Total |
10 |
3049 |
184 |
12 |
1243 |
217 |
||
|
Argemone Mexicana |
7 |
0 |
0 |
0 |
2 |
120 |
29 |
Pasture land |
|
Leucas abyssinica |
7 |
1 |
6 |
14 |
1 |
11 |
14 |
|
|
Musa X paradisiaca |
7 |
2 |
4 |
29 |
2 |
4 |
29 |
|
|
Rhus glutinosa subsp. neoglutinosa |
7 |
2 |
9 |
29 |
2 |
9 |
29 |
|
|
Ricinus communis |
7 |
3 |
11 |
43 |
3 |
11 |
43 |
|
|
Trigonella foenum-graecum |
7 |
0 |
0 |
0 |
4 |
320 |
47 |
|
|
Trifolium steudneri |
7 |
0 |
0 |
0 |
2 |
435 |
29 |
|
|
Vernonia amygdalina |
7 |
0 |
0 |
0 |
3 |
1450 |
43 |
|
|
Capsicum annum |
7 |
3 |
23 |
43 |
4 |
51 |
57 |
|
|
Total |
11 |
53 |
158 |
23 |
2411 |
320 |
||
|
Note: NPFO = Number of plots in which bee flora occurred, SS = Sample size |
||||||||
Abundance of bee flora was also crosschecked with the social survey or respondents view, which was almost similar. According to the data obtained from the respondents and field survey, the relative abundance of Leucas abyssinica, Becium grandiflorum (Hayelom site), Bidens spp. Hypoestes forskaolii, and Vernonia amygdalina was higher in Debre-Nazret and Hayelom kebelles (Table 4 and 5).
The Shannon diversity indices for the common bee flora species in the study areas were estimated at the two seasons (wet and dry) and different land use systems (Table 6). The observed number of species in wet and dry seasons was 30 and 27 respectively in closed forest of Debre-Nazret kebelle. Similarly the observed number of bee flora species in the wet and dry seasons was 17 and 14 respectively in closed forest land use system of Hayelom kebelle. Similar number of bee flora species was observed in both seasons in backyard of both study kebelles (Table 6).
In Debre-Nazret, species diversity was 2.69 and 2.46 in the wet and dry seasons respectively. In Hayelom, it was 2.02 in wet and 1.5 in dry seasons. Estimated Shannon diversity of the wet and dry seasons in the backyard land use system was 1.54 and 1.58 respectively in Debre-Nazret kebelle. The Shannon diversity of wet and dry seasons of the backyard land was 1.89 and 1.73 respectively in the Hayelom site. The Shannon evenness was calculated for all the land use systems of Debre-Nazret and Hayelom kebelles of the Tigray region of Ethiopia. (Table 6). The abundance and diversity of bee flora species in closed area was higher than the other land use systems, this increase the bee forage and biodiversity of the study areas.
Similarly, Emiru (2002) and Kindeya (2004) showed on closed forest to play a great role in increasing species biodiversity as well as maintaining biodiversity in the dryland areas.
|
Table 6. Mean Shannon diversity indices of the bee flora in Wet and Dry season based on land use system in Debre-Nazret and Hayelom kebelles |
|||||||||
|
Honey bee Flora Species |
Site |
Land use |
|||||||
|
Closed forest |
Backyards |
Pasture land |
Irrigated land |
||||||
|
Wet |
Dry |
Wet |
Dry |
Wet |
Dry |
Wet |
Dry |
||
|
Number of individuals (N) |
1 |
8131 |
2942 |
90 |
94 |
3129 |
609 |
1789 |
352 |
|
2 |
3844 |
624 |
81 |
74 |
3049 |
1243 |
53 |
2411 |
|
|
Observed number of species (S) |
1 |
30 |
27 |
9 |
9 |
4 |
5 |
9 |
9 |
|
2 |
17 |
14 |
9 |
8 |
5 |
6 |
5 |
9 |
|
|
Shannon diversity (Hꞌ) |
1 |
2.46 |
2.69 |
1.54 |
1.58 |
0.06 |
0.38 |
0.97 |
1.43 |
|
2 |
1.48 |
2.02 |
1.89 |
1.73 |
0.07 |
0.20 |
1.43 |
1.19 |
|
|
Shannon evenness (E) |
1 |
0.39 |
0.55 |
0.52 |
0.54 |
0.27 |
0.29 |
0.15 |
0.29 |
|
2 |
0.26 |
0.54 |
0.73 |
0.71 |
0.21 |
0.21 |
0.84 |
0.37 |
|
|
Note: Site 1= Debre-Nazret and Site 2 = Hayelom kebelle |
|||||||||
Family wise composition of the bee flora of Debre-Nazret and Hayelom kebelles is shown in figure 7.The dominant bee flora families are Lamiacea, Fabaceae and Asteraceae with frequency of 6, 6 and 4 respectively. Most of the bee flora families available in the kebelles have only one representative bee flora species (Fig.7).
 |
| Figure 7. Family wise composition of bee flora in Debre-Nazret and Hayelom kebelles |
From the documented bee flora plants of Debre-Nazret and Hayelom kebelles trees (25) consisted the highest number of the honey bee flora species from the other growth forms, while climbers (1) contained the lowest number of honey bee flora species (Fig.8).
 |
| Figure 8. Frequency distribution of growth form of bee forage/flora/ plants and their sources |
From the documented common bee forages/floras of Debre-Nazret and Hayelom kebelles, most (44) of the them serve the honey bees producing pollen and nectar and lower number (4) of the bee floras as sources of nectar (Fig.9).
 |
| Figure 9. Bee forages and their sources in Debre-Nazret and Hayelom kebelles |
From the sample household responses, honey bees visit almost all types of flowering plants around their hives. Plant species of various types are used for bee forage. In such cases local household respondents show preference towards plant species on the basis of number of flowers and attractiveness of honey bees towards the bee flora. In the study, preference ranking for ten selected plants was used to analyze the species importance for bee forage . Moreover, the plant species were selected based up on length of flowering periods, biomass of flowers, number of branches per plant, number of flowers per branch and honey bee attractiveness. From this study it was observed that, Becium grandiflorum has more number of branches per plant.Becium grandiflorum, Hypoestes forskaolii, Leucas abyssinica ,Eucalyptus camaldulensis, Croton macrostachys, Dodonaea angustifolia ,Otostegia integrifolia ,Carduus nyassanus , Rumex nervosus and Achyranthes aspera had mean number of flowers 21, 19, 16, 15,13,12,10,9,8 and 6 per branch, respectively (personal observation). Accordingly, (Table 7) showed Becium grandiflorum to be the most preferable bee flora species followed by Hypoestes forskaolii. The rank was given by selected seven household respondents of the study kebelles.
|
Table 7. Preference ranking of ten selected bee floras on attractiveness and number of flower |
||||||||||
|
Species |
Respondents |
|||||||||
|
R16 |
R32 |
R48 |
R64 |
R80 |
R96 |
R112 |
Total |
Mean |
Rank |
|
|
Becium grandiflorum (Lamiaceae) |
10 |
10 |
10 |
8 |
9 |
8 |
9 |
64 |
9.14 |
1st |
|
Hypoestes forskaolii (Acanthaceae) |
9 |
7 |
10 |
9 |
7 |
7 |
8 |
57 |
8.14 |
2nd |
|
Leucas abyssinica (Lamiaceae) |
7 |
8 |
7 |
7 |
10 |
5 |
6 |
50 |
7.13 |
3rd |
|
Eucalyptus camaldulensis (Myrtaceae) |
6 |
7 |
5 |
6 |
4 |
8 |
3 |
39 |
5.56 |
4th |
|
Croton macrostachys (Euphorbiaceae) |
5 |
4 |
4 |
4 |
4 |
5 |
6 |
32 |
4.57 |
5th |
|
Dodonaea angustifolia (Sapindaceae) |
5 |
4 |
5 |
3 |
4 |
3 |
7 |
31 |
4.41 |
6th |
|
Otostegia integrifolia (Lamiaceae) |
8 |
2 |
5 |
4 |
1 |
5 |
2 |
27 |
3.82 |
7th |
|
Carduus nyassanus (Asteraceae) |
3 |
1 |
6 |
3 |
4 |
3 |
5 |
25 |
3.57 |
8th |
|
Rumex nervosus (Polygonaceae) |
4 |
2 |
3 |
2 |
6 |
1 |
4 |
22 |
3.14 |
9th |
|
Achyranthes aspera (Amaranthaceae) |
1 |
2 |
2 |
5 |
4 |
3 |
3 |
20 |
2.82 |
10th |
 |
 |
| Becium grandiflorum (A) | Leucas abyssinica (B) |
 |
 |
| Hypoestes forskaolii (C) | Eucalyptus camaldulensis (D) |
| Figure 10. Photo of the best bee flora of Debre-Nazret (except A) and Hayelom (all) | |
The flowering time of the common bee flora species in the study areas was identified by the respondent households, key informants as well as during focus group discussion. Local beekeepers, extension agents, and horticulturalist are good source of information about the important bee plants in an area and their historic blooming times. Accordingly, the flowering time of the common bee flora was characterized as common and rare flowering time. Bista and Shivakoti (2001) noted that the flowering time of bee flora may differ from place to place due to variation in topography, climate and farming practices. For example the common flowering time of Leucas abyssinica, Trifolium spp. and Becium grandiflorum was from August to November. Hypoestes forskaolii and Bidens spp. commonly flower from August to December in Debre-Nazret kebelle (Table 8), whereas they flower from August to November in Hayelom kebelle (Table 7). The flowering time of most of bee flora like Becium grandiflorum, Carissa spinarum and Leucas abyssinica was commonly from September to October while most of the herbaceous species commonly flowered from August to October. But some herbaceous species like Argemone mexicana (Table 6 and 7) commonly flowered from December to March. The rare flowering time of bee flora species in the study areas was related with availability of rain and the species type. Some of the bee flora in the study areas have long flowering time (Eucalyptus camaldulensis, Rumex nervosus, Leucaena leucocephola), while some other species have short flowering time ( Bidens spp., Vicia faba, Rhus glutinosa, Guizotia abyssinica). The blooming period of the same bee flora species differs with the Debre-Nazret and Hayelom kebelles.
The peak period (August to October) is the important honey flow season in the Debre-Nazret and Hayelom kebelles. Previous study conducted in Ethiopia by Fichtl and Admasu 1994 also showed similar result. In addition, some species bloom from mid-March to May (Delaplane 2010). Therefore flowering calendar helps to identify dearth and harvesting periods of the local areas. Delaplane 2010 showed that in planning bee farming, it is important to choose a collection of plants that will produce unbroken succession of bloom throughout the season.
|
Table 8. Blooming period of common bee forages in Debre-Nazret kebelle |
||||||||||||
|
Species Name |
Blooming time (month) |
|||||||||||
|
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec |
Jan |
Feb |
Mar |
Apr |
May |
|
|
Acacia origena |
|
|
||||||||||
|
Achyranthes aspera |
||||||||||||
|
Agave sisalana |
||||||||||||
|
Aloe berhana |
||||||||||||
|
Andropogon abyssinicus |
|
|
|
|||||||||
|
Argemone Mexicana |
||||||||||||
|
Azadirachta indica |
|
|||||||||||
|
Bidens spp |
||||||||||||
|
Capsicum annum |
||||||||||||
|
Carduus nyassanus |
||||||||||||
|
Carica papaya |
||||||||||||
|
Carissa spinarum |
||||||||||||
|
Cordia africana |
||||||||||||
|
Croton macrostachys |
||||||||||||
|
Cynadon doctylon |
||||||||||||
|
Dodonaea angustifolia |
|
|
||||||||||
|
Erythrina abyssinica |
|
|||||||||||
|
Eucalyptus camaldulensis |
||||||||||||
|
Euclea schimperi |
||||||||||||
|
Euphorbium candelabrum |
|
|||||||||||
|
Guizotia abyssinica |
|
|||||||||||
|
Helianthus annuus |
||||||||||||
|
Hypoestes forskaolii |
|
|
||||||||||
|
Leucaena leucocephala |
||||||||||||
|
Leucas abyssinica |
|
|||||||||||
|
Mangifera indica |
|
|||||||||||
|
Olea europaea |
||||||||||||
|
Parkinsonia aculeata |
|
|||||||||||
|
Piliostigma thonningii |
||||||||||||
|
Prunus persica |
||||||||||||
|
Polyscias fulva |
||||||||||||
|
Psidium guajava |
||||||||||||
|
Rhamnus prinoides |
||||||||||||
|
Rhus glutinosa |
||||||||||||
|
Rumex nervosus |
||||||||||||
|
Satureja simensis |
||||||||||||
|
Schefflera abyssinica |
||||||||||||
|
Schinus molle |
||||||||||||
|
Sida schimperriana |
||||||||||||
|
Solanum incanum |
||||||||||||
|
Trigonella foenum-graecum |
||||||||||||
|
Trifolium steudneri |
||||||||||||
|
Vernonia amygdalina |
||||||||||||
|
Vicia faba |
||||||||||||
Note: = All time (After Rain), rare and Year round flowering period = Usual or common flowering period
|
||||||||||||
|
Table 9. Blooming period of common bee forages in Hayelom kebelle |
||||||||||||
|
Species Name |
Blooming time (month) |
|||||||||||
|
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec |
Jan |
Feb |
Mar |
Apr |
May |
|
|
Acacia origena |
||||||||||||
|
Achyranthes aspera |
||||||||||||
|
Aloe berhana |
||||||||||||
|
Andropogon abyssinicus |
||||||||||||
|
Argemone Mexicana |
||||||||||||
|
Azadirachta indica |
|
|||||||||||
|
Becium grandiflorum |
||||||||||||
|
Bidens spp |
||||||||||||
|
Capsicum annum |
||||||||||||
|
Carduus nyassanus |
||||||||||||
|
Carica papaya |
||||||||||||
|
Carissa spinarum |
||||||||||||
|
Cordia africana |
||||||||||||
|
Croton macrostachys |
||||||||||||
|
Cynadon doctylon |
||||||||||||
|
Dodonaea angustifolia |
||||||||||||
|
Eucalyptus camaldulensis |
||||||||||||
|
Euclea schimperi |
||||||||||||
|
Euphorbium candelabrum |
||||||||||||
|
Helianthus annuus |
||||||||||||
|
Hypoestes forskaolii |
||||||||||||
|
Leucaena leucocephala |
||||||||||||
|
Leucas abyssinica |
||||||||||||
|
Mangifera indica |
||||||||||||
|
Olea europaea |
||||||||||||
|
Opuntia ficus-indica |
||||||||||||
|
Parkinsonia aculeata |
||||||||||||
|
Piliostigma thonningii |
||||||||||||
|
Prunus persica |
||||||||||||
|
Polyscias fulva |
||||||||||||
|
Psidium guajava |
||||||||||||
|
Rhamnus prinoides |
||||||||||||
|
Rhus glutinosa |
||||||||||||
|
Rumex nervosus |
||||||||||||
|
Satureja simensis |
||||||||||||
|
Schefflera abyssinica |
||||||||||||
|
Schinus molle |
||||||||||||
|
Sida schimperriana |
||||||||||||
|
Solanum incanum |
||||||||||||
|
Trigonella foenum-graecum |
||||||||||||
|
Trifolium steudneri |
||||||||||||
|
Vernonia amygdalina |
||||||||||||
|
Vicia faba |
||||||||||||
| Note: = All time (After Rain), rare and Year round flowering period = Usual or common flowering period
|
||||||||||||
During the field survey, informants were interviewed on the current status of modern and traditional hive types of their areas. Based on response of households from the Debre-Nazret and Hayelom kebelles, honey production status for the peak harvesting time for the year 2012 was documented in table 10.Honey product of Debre-Nazret and Hayelom sample households was 5530 and 4370kg per year, respectively. According to the kebelles’ natural resources and Agricultural office report, 10-40 kg (average 30kg) of honey per hive was produced in one (two harvesting times per, if rain is available) harvesting period for the year 2012 in their kebelles (Table 10).
|
Table 10. Honey production status of Debre-Nazret and Hayelom kebelles |
||||||
|
No |
Debre-Nazret |
Hayelom |
||||
|
Product(kg) |
Frequency |
Percent |
Product(kg) |
Frequency |
Percent |
|
|
1 |
10 |
4 |
6.3 |
10 |
1 |
1.5 |
|
2 |
20 |
16 |
24.4 |
20 |
17 |
26 |
|
3 |
30 |
12 |
18.4 |
30 |
15 |
22.7 |
|
4 |
40 |
5 |
8 |
40 |
5 |
8 |
|
5 |
50 |
5 |
8 |
50 |
5 |
8 |
|
6 |
60 |
4 |
6.3 |
60 |
1 |
1.5 |
|
7 |
70 |
2 |
3.0 |
70 |
3 |
4.5 |
|
8 |
80 |
1 |
1.5 |
80 |
4 |
6.3 |
|
9 |
90 |
2 |
3.0 |
90 |
1 |
1.5 |
|
10 |
100 |
4 |
6.3 |
100 |
5 |
8 |
|
11 |
140 |
1 |
1.5 |
120 |
2 |
3.0 |
|
12 |
150 |
1 |
1.5 |
160 |
1 |
1.5 |
|
13 |
160 |
1 |
1.5 |
200 |
1 |
1.5 |
|
14 |
200 |
1 |
1.5 |
250 |
1 |
1.5 |
|
15 |
280 |
1 |
1.5 |
290 |
1 |
1.5 |
|
16 |
290 |
1 |
1.5 |
390 |
1 |
1.5 |
|
17 |
300 |
1 |
1.5 |
610 |
1 |
1.5 |
|
18 |
400 |
2 |
3.0 |
- |
- |
- |
|
19 |
1000 |
1 |
1.5 |
- |
- |
- |
|
Total |
5530 |
65 |
100 |
4370 |
65 |
100 |
The sample respondents were asked about their perception (experience) towards production of quality honey and season (months) with the year. The response from sample household heads of the two kebelles indicated in figure 10 show months (time) of harvesting and quality honey production of the areas.
The respondents chose very good harvesting time and honey production for the months of October and Novembe (Fig. 11). These months are peak harvesting periods in Debre-Nazret and Hayelom kebelles of the Tigray region. Eventhough the flowering period of the Debre-Nazret and Hayelom kebelles differs, the households harvest after the rainy season. The bees forages that flowers after harvesting time support the honey bee to survive with in and around their hives.
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| Figure 11. Relationship between months and Honey Production in Debre-Nazret and Hayelom |
From previous study of Admasu (1996), flowering time of plants varies from place to place, the reason might be due to differences in flowering period of the honey bee flora types of the study areas and the topography and climate variation. This variation in flowering period might emanate from the variations in topography, climate and seasons of the year. A few households responded that there was very good honey produced in the month of March (Fig. 11).
We would like to express our appreciation of Mekelle University for the financial support during the research work. We also would to thank the local informants and agricultural development administrators of the study areas.
Admasu Addi and Nuru Adgaba 2002 Effect of honeybee pollination on seed yield and oil content of Niger (Guizotia abyssinica): Proceedings of the first National Conference of Ethiopian Beekeepers Association, June 7-8, 1999, Addis Ababa, Ethiopia. 67-73
Admasu Addi 1996 Preliminary investigation on the taxonomy of Ethiopian honey bee flora. April 18-19, 1996. Proceedings of the 4th Annual Conference of the Ethiopian Society of Animal Production (ESAP): held in Addis Ababa, Ethiopia. 181-186
Alaux, C, Ducloz, F, Crauser, D and Le Conte, Y 2010 Diet effects on honeybee immunocompetence, Biological Lettetters
Amsalu Bezabeh, Nuru Adgaba and Radloff, H 2003 Multivariate morphometric analysis of honeybees in the Ethiopian region Apidolgie 35: 71-81
Ayalew Kassaye 2006 The loss of some natural plant species in Tigray and the concern to the living conditions of honeybees. loss of natural plants: Proceedings of the 5 th Annual National Conference of Ethiopian Beekeepers Association. 8-15
Bedru Babulo, Muys B and Mathiji E 2006 Economic valuation methods of forest rehabilitation in exclosures Journal of Drylands. 1:165-170
Bista S and Shivakoti P G 2001 Honeybee flora at Kabre Dolakha District. Journal of Napal Agricultural Research 5: 16-25
Cunningham A B 1996 People, park and plant use recommendations for multiple use Zones and development alternatives around Bwindi, Uganda, UNESCO, Paris. People and plants working paper Walter M and Hoft R eds 4: 18-23
Delaplane, S McLaurin, J and Thomas, A 2010 Bee pollination of Georgia crop plants GA (University of Georgia), Cooperative extension service, the College of Agricultural and Environmental Science Bulletin 1106
Diver, S 2002 Phenology web links: (1) sequence of bloom, floral calendars, what’s in bloom; (2) birds, bees, insects and weeds National Sustainable Agriculture Information Service, ATTRA United States 23-29
Edwards S, Mesfin Tadesse and Hedberg, I eds 1995 Flora of Ethiopia and Eritrea Canellaceae to Euphorbiaceae.The National Herbarium, AAU, Addis Ababa and Uppsala 2: 71-73
Emiru Birhane 2002 Actual and Potential Contributions of Enclosure of Enhance Biodiversity in Dry Lands of Eastern Tigray with Particular Emphasis on Woody Plants, M.Sc. Thesis. Sweden.
Fisseha Mesfin 2007 An Ethnobotanical study of medicinal plants in Wonago Woreda, SNNPR, Ethiopia.MSc thesis, AAU, Ethiopia
Fichtl R and Admasu Addi 1994 Honey bee flora of Ethiopia. The National Herbarium, Addis Ababa University and Deutscher Entwicklungsdieenst (DED) Mergaf Verlag, Germany
Gidey Yirga and Mekonen Teferri 2010 Participatory technology and constraints assessment to improve the livelihood of beekeepers in Tigray Region, northern Ethiopia Mekelle University 2: 76-92.
Girma Deffar 1998 Non-Wood Forest Products in Ethiopia EC-FAO Partnership Programme 1998-2000 Addis Ababa
Haftom Gebremedhn and Yaynishet Tesfay 2012 Identification and evaluation propagation techniques of Hypoestes forskaolii (Grbia)as bee fodder for smallholder farmers Livestock Research for Rural Development 24
Jacobs, F Simoens C,Graaf D and Deckers J 2006 Scope for non-wood forest products income generation from rehabilitation areas: focus on beekeeping. Journal of the Drylands 1: 171-185
Keller I, Fluri P and Imdorf A 2005 Pollen nutrition and colony development in honey bees, Part II, Bee World 86: 27-34
Kindeya Gebrehiwet 2004 Dryland agroforestry strategy for Ethiopia September 1 -3, 2004 Drylands Agroforestry: Proceedings Headquarters, Nairobi- Kenya
Liseki S and Boniphace T 2008 Honeybee colony development and the flowering calendar. Journal of Bees for Development 32: 89
Martin G J 1995 Ethnobotany A method manua Royal botanical garden, Chapman and Hall, Kew, London 116-120
Mbah C and Amao A 2004 Natural foods and feeding habits of the African honey bee Apis mellifera adansonii Latrielle, in Zaria, Northern Nigeria World Journal of Science 4: 11-14
Meaza Gebreyohannes 2010 Socio-Economic Analysis of Market Oriented Beekeeping in Atsbi Wemberta District of Eastern Zone, Tigray Region, Msc Thesis.
Melaku Girma, Shifa Ballo, Azage Tegegne, Nigatu Alemayehu and Lulseged Belayhun 2008 Approaches, methods and process for innovative apiculture development: Experience from Ada'a-Liban Woreda, Oromia Regional State, Ethiopia Improving Productivity and Market Success (IPMS) of Ethiopian Farmer Project Working Paper 8 ILRI (International Live Stock Institute), Nairobi Kenya 48
Michener, C.D. 2007 The bees of the world, 2nd edition, The Johns Hopkins University Press, Baltimore and London, USA and UK 12-19
Ministry of Agriculture (MOA) 2003 Comprehensive bees and beeswax marketing, 2nd draft MOA, Addis Ababa, Ethiopia
Shannon C 1948 A mathematical theory of communication The Bell System Technical Journal 27: 11-15
Tessega Belie 2009 Honeybee production and marketing Systems, constraints and opportunities in Burie District of Amhara Region, Ethiopia M.Sc Thesis Bahir Dar University, Ethiopia
Zemede Asfaw 2001 The Role of Home Garden in Production and Conservation of Medicinal Plants In: Proceeding of the National Work shop on Biodiversity Conservation and Sustainable use of Medicinal plants in Ethiopia, 28 April -01 May 1998 Medhin Weldu and Abebe Demissie eds, IBCR, A.A, Ethiopia
Received 14 May 2016; Accepted 17 May 2016; Published 1 July 2016