Honeybee health

A honeybee colony housed in an organic garden should radically improve pollination (and fruit set), but flowers in one backyard are insufficient to feed a strong colony of 30 – 80,000 honeybees.

There’s no commercial horticulture or agriculture in or near the suburb, so the associated risk of pesticide poisoning is low. The council and state rail regularly use glyphosate to spray weeds along street kerbs, railway fenceline and the weedy grass verge alongside the railway line, but that’s not a direct risk to bees.

According to ‘The bee book – beekeeping in Australia’ by Peter Warhurst & Roger Goebel (published by DPI Queensland, ISBN 0-7345-0330-X), the best beekeeping guide, honeybees need a varied source of pollen, which provides protein, and a variety of nectars, for carbohydrate, for a balanced diet.

‘Honey Flora of Queensland’, by S.T. Blake & C. Roff (published by Qld DPI, ISBN 0-7242-2371-1) is an interesting read for a gardener. This explains that not all pollens and nectars are equal. There can be a great variation in their respective nutritional value. Certain plants provide either pollen or nectar and there’s a wide variation in their quality. Productivity is strongly linked to the season, rainfall and plant condition.

Out of all our potential sources there seems to be just one plant, the Broad-leaved Paperbark, Melaleuca leucadendron, a local native, that offers both pollen and nectar in high volumes and both are of high nutritional value.

Honey flora

Generally, the most prolific sources of pollen and nectar for commercial honey production are native plants. The most significant Australian genera are Eucalyptus, Melaleuca, Leptospermum, Acacia and Casuarina, as well as various mangroves and Banksia. These occur in large numbers and individuals produce in large quantities.

Casuarina is a wind pollinated genus, yet bees gather large quantities of pollen from them. Sweetcorn, another wind pollinated plant, is another important pollen source. A big surprise to this gardener.

Wynnum honey flora

In our suburb there’s never been any rainforest, sand dunes or Wallum heathland, but there are small patches of remnant dry sclerophyll forest and Grey mangroves are recovering along the shoreline of Moreton Bay.

I expect our bees will work these major local food sources during their peak flowering times, rather than working our own and neighbouring gardens. Such wild plants contribute the major ‘honey flow’ that apiarists count on for rapid colony growth and honey production.

Crop pollination services are essential to agriculture too – without them 40% of our harvests would fail. Mango, avocado, macadamia, almond, cherry, watermelon and pumpkin are heavily dependent. Having a hive will definitely assist and improve pollination and yeild of local productive gardens.

For a hobbyist, local garden plants and street trees – our urban forest – can be significant food sources. Many of these species aren’t mentioned in honey flora books, probably because in the wild they don’t occur in large stands. Some of the most notable bee trees in our suburb are Poinciana, Mango and Ivory curl tree.

I’ll have to find out if other significant urban forest species are of value, such as Bangalow palm, the weedy Queen palm, Tuckeroo and Tulipwood.

Botanically speaking, SE Qld and the Northern Rivers of NSW are part of the Macleay-McPherson Overlap, which is particularly rich in species and ecosystems, so the honey flora book serves apiarists in that region as well as it does ours.

Another twist to honey flora is that apiarists value plants differently to gardeners. To the gardener, Echium plantagineum is the weed Paterson’s Curse. To the apiarist it’s Salvation Jane. I’m curious to discover what the pure Echium honey, sold at the beekeeping supplies store, tastes like.

Estimates as to how far honeybees will fly to work flowers varies according to different authorities. In poor conditions they will fly up to 10km. If sufficient food is available more locally, they will remain within 1 – 4 km from the hive. Checking the local street directory helps form a picture of the types of food sources available.

Significant sources within one kilometre

Naturally occurring natives

Teranora Park

• Grey mangrove, Avicennia marina subsp. australasica;
• Sand hibiscus, Hibiscus tiliaceus;
• Swamp she-oak, Casuarina glauca

Wynnum golf course, Kitchener Park and Memorial Park

• Broad-leaved paperbark, Melaleuca leucadendron;
• Forest Red gum, Eucalyptus tereticornis;

Wynnum creek – mostly weeds, but some of the above natives survive;

The urban forest

• Bangalow palm, Archontophoenix cunninghamiana;
• Cadagi, Eucalyptus torelliana, a cultivated native weed;
• Cocos palm, Syagrus romanzoffiana, a cultivated exotic weed;
• Forest red gum, Eucalyptus tereticornis;
• Ivory Curl tree, Buckinghamia celsissima;
• Jacaranda, Jacaranda mimosifolia (?)*
• Leopard tree, Caesalpinia ferrea (?)
• Lillypilly, Various Syzygium species (?)
• Mango, Mangifera indica;
• Poinciana, Delonix regia;
• Pride of Bolivia, Tipuana tipu, an exotic cultivated weed (?)
• Tuckeroo, Cupaniopsis anacardioides (?)
• Tulipwood, Harpullia pendula (?)
• Weeping lillypilly, Waterhousia floribunda (?)
• Yellow poinciana, Peltophorum pterocarpum (?)

* a query denotes my uncertainty as to a species’ usefulness to bees

Significant local weeds

• Broad-leaved pepper tree, Schinus terebinthifolius, an invasive weed (?)
• Common plantain, Plantago lanceolata (pollen is highly allergenic);
• Flatweed, Hypochaeris radicata; a common lawn weed;
• Siratro, Macroptilium atropurpureum – an escaped pasture plant;
• White clover, Trifolium repens;

Significant sources within two kilometres

The boundary streets to this zone include Pritchard Street (north), Crawford Road (west) and Gordon Parade (south).

Remnant bush blocks

These are mostly along Wynnum Rd and towards Lindum railway station. Much is being cleared for housing.

• Broad-leaved paperbark;
• Forest red gum;
• Black wattle, Acacia concurrens;

Significant horticultural crops

None

Significant sources within ten kilometres

At this range bees will have crossed the Brisbane River to the airport and beyond. The range of plants is greater as are the size of remnant bush blocks, but essentially the plant communities, urban forest trees and domestic garden flora are similar.

Jerry Coleby-Williams
3rd April 2008