The deciduous-fruit pollination season lasts only a few weeks, but bees must eat 12 months a year. Finding suitable forage sites is a major headache for beekeepers – and diminishing forage will eventually limit pollination hives. “Over the next 15 years, I believe that the availability of good quality pollination units is going to become one of the biggest risks to the industry,” says James Hutton-Squire. He should know: he manages a commercial pome-fruit unit for Hutton-Squire Farms in Elgin and researched honeybee forage in the context of agriculture for his master’s degree in agriculture at Stellenbosch University. Like most growers, Hutton-Squire relies on rented hives for pollination because Hutton-Squire Farms lack sufficient forage to support the required hives year-round. An on-going WWF South Africa-led project aims to quantify the mismatch between pollination demand and forage resources. “We’re trying to create a new measurement that we call a pollination forage footprint,” says Kirstie Koen, project coordinator for the Elgin Valley. She is gathering data on the number of hives required for pollination in Elgin and relating that to the amount of forage needed and available. The long-term goal is supporting beekeepers and fruit growers by unlocking exis-ting forage sites and creating new sources.
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The forage calendar Bees obtain protein and lipids from pollen, and energy from nectar. Plants differ in the quality and quantity of pollen and nectar their flowers offer. Most plants also only flower du- ring specific months. This means that beekee-pers need multiple forage sites during the year. In pollination season, bees from rented hives mostly forage in orchards, and pome- and stone-fruit blossoms are generally not a high-quality food source. This contributes to the decline of pollinating colonies. After pollination season, beekeepers depend on eucalyptus, as few native Western Cape plants flower in summer. Beekeepers will move hives to fynbos once it begins flowering, usually when the rainy season starts in autumn or winter. During winter, bee population growth slows, so colonies have a lower pollen requirement. In late winter, beekeepers put their hives in canola, which is excellent pollen- and nectar-rich forage for building strong pollination colonies. Understanding the obstacles to utilising various forage types is the first step toward increasing availability.
Eucalyptus For part of his master’s degree research, Hutton-Squire searched through nearly a century’s back copies of the South African Bee Journal for mentions of forage sources. He also sent questionnaires to beekeepers requesting data on their current foraging patterns. This allowed him to compare what today’s beekeepers value as forage sources with historical records. “As the bee industry grew, eucalyptus became increasingly important,” he says. “And it remains a huge portion of the current forage, specifically for the Western Cape in summer.” Beekeepers reported that nearly 80% of Western Cape hives use eucalyptus. Unfortunately, eucalyptus trees are exotic to SA, and six of the 85 species here are classified as invasives. These include the sugar gum (Eucalyptus cladocalyx) and the saligna gum (Eucalyptus grandis) – critically important honeybee forage sources. Eucalyptus was originally introduced for forestry, and many existing trees grow in woodlots. “One aspect of our project is to identify woodlots, making sure they are in non-vulnerable areas, and assisting land- owners to get permits for them,” says Koen. Not all invasive eucalyptus must be removed. WWF has created a free resource for land- owners that explains the relevant regulations.
Fynbos The Elgin Valley and surrounding mountains include large fynbos areas, but much of this lies within the Kogelberg Biosphere nature reserves. “Cape Nature are the custodians of most natural state land in the Western Cape,” explains Hutton-Squire, “and they don’t allow managed beehives. I agree with their approach.” Regarding fynbos within private conser-vancies, Koen says it’s up to the landowners whether or not to grant beekeepers access for placing hives. However, obtaining access isn’t the only obstacle to using fynbos. In Elgin, Hutton-Squire notes that hives in fynbos may be subject to vandalism and at risk of wildfires – these hazards also pertain to woodlots. When beekeepers manage to find suitable areas, they need to figure out how many hives the available forage can support. Experts agree that quantifying the honeybee-carrying capacity of fynbos is tricky. “Theoretically, you can measure the nectar and pollen availability in an area of fynbos,” says Koen. “But it’s going to vary each season and depend on the age and species composition of the fynbos.” A suboptimal way of learning carrying capacity is to put out hives. If there are too many, some colonies will abscond in search of more floriferous pastures – an outcome beekeepers try to avoid.
Cover crops Deciduous-fruit growers are increasingly experimenting with cover crops to improve soil health, but an orchard floor of diverse flowering plants could hold additional benefits. Researchers such as Matthew Addison, Crop Protection Programme Manager at Hortgro Science, maintain that flowering cover crops promote pollinator activity. Hutton-Squire agrees. “I believe that bees are extremely sensitive to pheromones and the smell and look of an orchard,” he says. Based on his observations, diversity on the orchard floor is better for pollination than clean ridges and work rows. On the other hand, some argue that flowering cover crops lure bees away from the primary crop, thereby reducing pollination efficiency. A new Hortgro-funded project aims to determine how honeybee visitation and fruit yields relate to cover crops in pome- and stone-fruit orchards. While Koen is not collecting data on orchard pollination, she thinks cover crops are potential emergency forage to sustain bees during pollination season, should hives remain in orchards for a week or so longer than planned. Cover crops can slow or even stop the colony declines that frequently accompany fruit-tree pollination. Koen has also seen cover crops contributing to forage throughout the year on a farm that establishes summer and winter cover crops. Although most cover crops flower in spring, incorporating winter-flowering species could augment natural forage while orchards are dormant.
The future for forage WWF will report its findings on the pollination demand and forage availability of the Elgin Valley and the Langkloof later this year. It’s already clear that Elgin fruit growers require more pollination hives than can be supported by forage within their region. The hope is that greater awareness of the mismatch will encourage landowners to make forage available to beekeepers – or even to plant forage corridors. “What WWF is doing is very relevant,” comments Hutton-Squire. “In the apple industry, as it currently stands, it’s not possible for us to produce enough forage to sustain the bees we need. Ultimately, we rely heavily on the beekeepers, and they rely heavily on privately owned land.” While WWF is committed to eucalyptus removal in sensitive areas such as along rivers, it recognises that eucalyptus complements the natural forage provided by fynbos. “WWF has a different project removing aliens down river lines and rehabilitating those with bee-friendly plants so that we can increase natural forage and create wildlife corridors,” says Koen. She is compiling a list of bee-friendly plants to assist people managing land in choosing suitable forage species. Ultimately, Koen wants more people to step up and help feed bees. “What I’m trying to achieve is to remind people that pollination doesn’t stop with the pollination season,” she says. “If you have the potential to produce forage on your land, please do so.”
