BEES AND POLLINATION

Staci Siler

Special thanks to: Bill Grayson

Journeyman Class - 2017

What happens during pollination?

Nectary

Poor pollination in the field

• Poorly pollinated

cucumber

• Well-pollinated

cucumber

Different ways to pollinate plants

■ Wind

■ Water

■ Animals

Only about 1% of all pollen successfully reaches a stigma.

Nevertheless, pollination by animals is both more common and

usually more effective than alternative methods using wind or

water. Also, animal pollination is usually associated with a more

rapid ‘speciation’ of plants. (Pollination and Floral Ecology, pg.

3)

Breakfast with pollinators

Breakfast without pollinators

Bees in pollination

■ Honey Bee Pollination produces 35% of human

food sources or 1 bite in 3

■ Global Agriculture Products - $217 billion

■ USA Agriculture Products - $18 – 27 billion

– Alfalfa Seed & Forage - $7 billion

– Apples - $1.5 billion

– Almonds - $1.1 billion [US leads world in

production]

– Berries - $2.5 billion

Different types of pollinators

Bumble bees – useful for greenhouses and tomatoes (buzz pollination) – Identification: head is smaller than thorax, hair on thorax and abdomen, pollen baskets on side of legs

Carpenter bees – useful for local pollination –Identification: head is the same size as the thorax, abdomen is shiny

Miner bees – useful for local pollination – found only at certain times of the year – certain species look very similar to honey bees. Typically, area they nest in helps tell them from honey bees.

More good pollinators

Leafcutter bees – Known as orchard bees. They have a very high rate of pollination, even better than honey bees, but their colonies are smaller and they don’t forage far from their nest. They pollinate wildflowers, fruits, vegetables. Some are even used commercially to pollinate alfalfa and blueberries. They cut leaves in a circular pattern and line their egg cells with it but will use other items if necessary. Identification: Resemble honey bees in size and appearance. One exception is that the pollen basket is on abdomen.

Mason bees – Also known as orchard bees. Very efficient pollinators of orchards, used to pollinate sprint fruit trees, flowers, and vegetables. Seals eggs in with pollen, capped over with mud. Identification: carries pollen on the underside of the abdomen. Color varies greatly.

Other interesting pollinators

■ Flies

■ Butterflies and Monarchs

■ Birds

■ Bats

■ Marsupials

■ Mammals

■ Lizards

■ Spiders (crab spiders and jumping spiders have been known to ingest nectar while waiting for prey so can, inadvertently,

pollinate)

The Honey Bee

Benefits of honey bees used for pollination

• Number one pollinator in the world

• 12 or more trips from the hive per day

• 8 foraging trips = almost 700 flowers per bee

• LOTS of bees in each colony

• Each trip confined to one plant flower type –‘flower fidelity’

• Goes up to five miles from

the colony in search of

food

• Wider forage area

increases genetic diversity

of plants

Some SC crops honey bees are used in for pollination

■ Watermelon

■ Blackberries

■ Cotton

■ Soybean

■ Cantaloupe

■ Cucumber

■ Squash

■ Blueberries

– And more!!!!

How do bees find flowers to pollinate?

■ Round dance – less then 10 meters away from

hive

■ Sickle dance – between 10 and 100 meters from

hive

■ Waggle dance – greater than 100 meters from hive

How do bees collect pollen

• Body hair has a ‘static’

charge and collects pollen

• Worker bees employ their

antenna plus front and

middle legs to comb and

store pollen

• Bees of the Megachilidae

family have a scopa

located on the abdomen.

Most other bee types

collect pollen on their hind

legs.

How do bees collect pollenPollen press

Corbicula

What do they do with collected nectar and pollen??

■ When bees come back from foraging on nectar,

they give the nectar to a house bee and then

resume foraging.

■ When bees come back from foraging with pollen,

they go to the brood area, back into the cell, and

‘kick’ the pollen pellet off into the cell. ‘Dry’ pollen

was brought in recently. Pollen with a ‘wet’

appearance is called ‘bee bread’ and is ready for

consumption.

Why do bees pollinate??

• Nectar is the bees’ source of carbohydrates

• Nectar’s sugar content averages 30% and bees convert nectar into honey, having 18.6% moisture content or less

• Pollen is the bees’ source of protein – pollen can contain from 8 to 40% protein.

• Pollen gathering is driven by brood production.

• Bees are descendants of wasps. Wasps require protein but derive it from insects. Bees need protein but derive it from pollen.

Consumption of pollenLarvae

■ Bees start digesting pollen – as larvae - from 42 to 52 hours old

and consume mass quantities until 5 days old

■ Each larvae requires 100 mg of pollen to complete development.

■ It takes 1 pound of pollen to raise 4,000 bees.

Adults

■ Protein (pollen) is necessary for adult bees until 10 – 14 days old,

when bees are preparing to forage, at which time they switch over

to carbs (honey/nectar)

■ Polyethism: age-derived tasks. If necessary, bees can forage as

young as four days old but typically they forage at 20 days.

■ Some bees are pollen gatherers, some are nectar, some are both.

It is determined by the needs of the colony and genetics.

Bee health and pollen?

■ Unlike humans, insects can’t produce sterols. They

need to get sterols from their environment. Sterols are

important components of cellular membranes, are the

precursors for many hormones, and play a role in

regulating genes. Sterols are found in pollen.

■ The protein derived from pollen aids in tissue and

muscle development and with the production of food

for their young via the hypopharengeal glands

■ A varied diet of pollen provides all ten essential amino

acids bees need to thrive.

■ Pollen also has vitamins, minerals, and fatty acids – all

necessary for the health of bees.

Other interesting things of note:

■ Bees have a ‘timing’ sense and will return to flowers at

set times each day

■ There are laws prohibiting bees from being around when

seedless varieties of plants are in bloom. Pollination

would cause them to grow seeds.

▪ Pollen grains from different flowers have

different shapes and colors. Honey can

be identified by the amount and type of

pollen grains in it. Ultra-filtered honey is

illegal because it filters out all the pollen

so the honey can not be identified as to

origin

More cool things of note:

■ If pollen count of a honey registers as 51%

or higher of one type of pollen, the honey

can legally be labeled as that particular type

of honey (ex: blackberry honey). Otherwise,

the honey must be given a generic label –

wildflower honey

■ Pollen pellets can vary in color from green

and white to red, black, violet, etc., but are

usually homogenous – all pollen in the

individual pellet was derived from one type

flower. The flower type determines the color

of the pollen

Some plants good for bees

• Holly (Ilex spp.)

• Privet (Ligustrum spp.)

• Red Maple (Acer rubrum)

• Rosemary (Rosmarinus officinalis)

• Schweinitz’s sunflower (Helianthus

schweinitzii)

• Sweet Clover (Melilotus spp.)

• Tulip Poplar (Liriodendron tulipifera)

• Aster (Aster spp.)

• Basil (Ocimum basilicum)

• Black Gum (Nyssa silvatica)

• Black-eyed Susan (Rudbeckia hirta)

• Blackberry (Rubus spp.)

• Buckwheat (Fagopyrum esculentum)

• Crimson Clover (Trifolium incarnatum)

• Goldenrod (Solidago spp.)

Commercial pollination

Pumpkins – July –mid-August

Blueberries – JuneCranberries – late June, mid-July

Apples – mid-April to mid-May

Citrus – mid-March to mid-April

Brazillian Pepper –August to January

Almonds – Feb to mid March

Commercial pollination

Almonds – California

Cherries – Oregon

Apples – Washington State, North Carolina, Pennsylvania

Cranberries – Wisconsin, Maine & New Jersey

Blueberries – Maine & North Carolina

Vegetables & Fruit – South Carolina, Georgia, Florida, Pennsylvania

Timing of appearance of bees in some SC crops

■ Apples: arrival must precede first blossom

– known as ‘King’ bloom

■ Cucumbers: arrival of bees must not

happen until after 15% of crop is in bloom.

Nectar is of such low sugar quantity that

they experience a ‘negative’ honey flow

working it. If they find anything else to work,

they will.

■ Squash: blooms close up in the afternoon

Some problems with crop pollination

■ Monoculture

■ Increased pressure from pests (varroa)

■ Overheating from travel (stress)

■ Exposure to lots of pesticides

Pesticides

– Some chemicals, which are non-toxic to bees,

become highly toxic when used in combination with,

or around other insecticides which, on their own,

are also in small enough amounts as to be labeled

non-toxic to bees.

Example: fungicides and coumaphos

References:

■ The Hive and the Honey Bee

■ Pollination and Floral Ecology

Special thanks to Bill Grayson – Master Beekeeper and Master Gardener.

His presentation on Pollination was a great source reference for this

presentation

Dr. John Strang, Univ. of Kentucky

Dr. Mike Hood, Clemson University

South Carolina Beekeepers Association - http://www.scstatebeekeepers.org/

California Almond Board

http://www.almonds.com/sites/default/files/content/attachments/hone

y_bee_best_management_practices_for_ca_almonds.pdf

Questions???