A Pollination Contract for a Two-Hectare Litchi Orchard
A litchi grower near Muzaffarnagar with 2 hectares of bearing trees (flowering mid-February to mid-March) asks Sunil to bring his bees for pollination. Sunil has 28 Apis mellifera colonies: 12 strong (8–10 frames of bees with brood), 10 medium (5–6 frames) and 6 weak (3 frames, recently united from a poor winter). The orchard has a tube-well and a north-side windbreak of eucalyptus, but the grower has three insecticide sprays scheduled on his calendar during flowering, for thrips and mites, and says he cannot postpone them because the neighbouring orchards are spraying too. The grower's offer is a flat payment for the season and he is unwilling to pay per colony. Sunil's own honey flow from mustard is finishing and he would otherwise move to eucalyptus in the first week of March. Moving colonies costs him ₹400 per colony per trip, and he can only move at night.
1. How many colonies should Sunil place, and which of his 28? Justify the choice with pollination and foraging reasoning rather than a fixed number.
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The relevant currency is frames of bees, not boxes. Pollination is done by foragers, and a 3-frame colony may field fewer than a third of the foragers of a 9-frame colony. The extension recommendation for litchi is around 5 colonies per hectare, but that assumes strong colonies; with mixed stock Sunil should convert to bee strength.
Arithmetic: 2 ha at 5 strong-colony equivalents = 10 strong units. Taking his 12 strong colonies as 1 unit each, the 10 medium as about 0.6 and the 6 weak as 0.3, his whole apiary is only about 12 + 6 + 1.8 ≈ 20 units spread over 28 boxes.
Decision: place the 12 strong and the best 6 medium colonies - about 15–18 boxes, roughly 15 strong-equivalents on 2 ha, which is generous but justified by litchi's short, heavy bloom and by the fact that cool February mornings reduce flight hours. Leave the 6 weak colonies behind to build up on mustard/eucalyptus; moving them wastes ₹2,400 in transport and pollinates almost nothing.
Also: set the hives inside or at the edge of the orchard so that most foraging is within 200–500 m. Litchi is highly attractive for both nectar and pollen, so bees will stay on it while it lasts, but they will drift to mustard/eucalyptus within 1–3 km once the litchi bloom declines - which is why the contract should cover only the flowering window.
2. Give a placement and in-orchard management plan for the four weeks of bloom.
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Placement:
- Four groups of 3–5 colonies (not one block), spaced about 150–200 m apart through the orchard, so the whole 2 ha is within 250 m of a hive group and bee movement covers the canopy evenly.
- Entrances facing away from the prevailing wind and towards the morning sun; the eucalyptus windbreak on the north is useful but keep hives 15–20 m clear of it so that shade is not permanent and gum/leaf litter does not sit on the hives.
- Stands on bricks or pallets, level, 30–45 cm high, with the entrance clear of grass.
During the four weeks:
- Move the colonies at night with entrances closed and a water spray on the screen; open at dawn. Expect some field-bee drift at the new site for two days.
- Provide clean water in shallow feeders with floating sticks - litchi nectar is dilute and the brood will need water; the tube-well is a distance away and bees will otherwise drown in it or in the spray tank.
- Do not open hives for long inspections in cool weather - brief entrance checks only; a chilled brood nest in February sets the colony back.
- Do not extract during the bloom; leave stores. The main income here is the pollination fee, and disruption reduces foraging.
- Watch for robbing once the bloom ends, and reduce entrances.
3. The three in-bloom insecticide sprays are the main risk. How should Sunil handle this technically and in the contract, and what would make him decline the job?
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Technical handling:
- The safest window is after sunset, when the bees are inside; the residue dries overnight and the following day's exposure is much lower. Sunil should ask for the exact product, dose and date and check whether it is a neonicotinoid or a dustable powder - the two worst cases, because dust drifts onto flowers and systemics contaminate nectar and pollen.
- Close or screen the entrances on spray evenings, and open them at dawn after the spray has dried; a damp cloth over the entrance screen keeps bees in without suffocation for short periods.
- Ask for the pre-bloom and post-petal-fall sprays to be moved, since thrips and mite pressure is often manageable before anthesis; the flowering week is the one window to protect.
- Keep a sample of any dead bees and record spray dates - this is the evidence if a claim is needed.
Contract points: name the notice period (48 hours), the products that will not be used during flowering, the payment schedule, and that liability for colony loss from spraying lies with the grower. Sunil should convert the flat payment into a rate that covers his ₹400/colony transport plus the honey he forgoes on the eucalyptus flow.
Decline if: the grower insists on a flowering-period neonicotinoid or dust spray and refuses night application, or if neighbouring orchards spray without notice - a flat fee does not compensate for losing 15 colonies, which would cost far more than the contract is worth.