Veronica Johnson, Maryland Department of Agriculture
A pollinator is any organism that transfers pollen –the male genetic material of plants- from one flower to the next, resulting in the production of fertile seeds. Pollinators include birds, bats, bees, butterflies, beetles and some small mammals. Bees are the most efficient of the pollinators, with some species capable of visiting up to 6 thousand flowers in a single day. This high rate of flower visitation is important considering between 75% and 95% of all flowering plants on Earth need help with pollination. These plants include the countless fruits, vegetables and nuts that constitute an important part of our diets. In fact, pollinators are responsible for one out of every three bites of food that we eat. Honey bees alone contribute between $1.2 and $5.4 billion in agricultural productivity in the U.S. Unfortunately, pollinator populations are changing. Many populations are in decline, primarily due to loss of feeding and nesting habitats. However, pollution, chemical misuse, disease and changing weather patterns are also contributing to shrinking pollinator populations.
In addition to the many challenges bees already face, recent studies have implicated sub-lethal doses of neonicotinoid pesticides in both honey bee and native bee population declines in many countries. Neonicotinoid pesticides first became available for use on farms and ornamental landscapes in the mid-1990s. Due to their comparatively low mammalian (including human) toxicity, they have gradually replaced other insecticides to become one of the most commonly used pesticides today. Much is yet to be known about the impacts of neonicotinoids on pollinators; however, sub-lethal doses in pollen have been shown to negatively affect foraging ability, survival, and queen production in many pollinator species. Honey bees exposed to sub-lethal doses of neonicotinoids can experience problems with flight and navigation, have reduced taste sensitivity and slower learning of new tasks – impacting foraging ability and hive productivity. Bumble bees exposed to sublethal doses of neonicotinoid pesticides have been shown to have reduced food consumption, reproduction, worker survival rates, colony survival and foraging activity. Queen production is also significantly reduced, potentially lowering overall bumble bee populations because fewer colonies are established the following year. Additionally, clothianidin, a type of neonicotinoid, has recently been shown to negatively impact the natural defense system of bees – known as “social immunity”. Social immunity is a tactic used by bees whereby sick, dying, and dead bees are thrown out of the colony. Neonicotinoid-exposed hives displayed less of this behavior, allowing sick bees to remain in the hive and spread infections.
Protect Bees From Pesticides
o Use Integrated Pest Management, or IPM, principles to control pests and only spray when necessary.
o Spray after sunset when bees have stopped foraging – morning and afternoon sprays are much more likely to poison bees directly.
o Leave an unsprayed crop buffer at field margins wherever possible to minimize drift to hedgerows, wildflowers and bee nesting areas.
o Avoid applying insecticides to flowering plants or areas where pollinators may be nesting.
o Look for the EPA bee hazard icon (right) on pesticide labels. This label signifies the pesticide is a potential hazard to bees.
o Look for pollinator language under the ‘Directions for Use’ section of the pesticide label.
o Choose sprayer and nozzle configurations designed to reduce drift and minimize droplets less than 150 microns, which drift farther.
REMEMBER: WHEN USING PESTICIDES MAKE SURE TO FOLLOW LABEL DIRECTIONS EXACTLY – THE LABEL IS THE LAW!
Preserve Natural Bee Habitats
o Preserve natural bee nesting areas by leaving field borders, woodlots, ditch banks, stream and pond edges,
hedgerows, utility line easements, land around garages 
and barns, roadsides, wetlands, and south-
facing embankments unmanaged. These areas provide spaces where bees can safely nest, raise their
young and overwinter.
o Whenever possible, avoid disturbing existing ground nests – which resemble ant hills (left).
Provide Floral and Nectar Resources
Leaving weeds such as chicory, clovers, dandelion, henbit, mustards, ox-eye daisy, and yarrow to bloom in areas where they will not cause problems with crop competition can provide excellent forage for bees, especially early in the growing season.
o Flowering cover crops like red and crimson clovers, spring-blooming canola, buckwheat, Austrian winter pea, and hairy vetch provide pollen and nectar resources during otherwise fallow periods.
For more information on protecting Maryland’s pollinators, check out the Maryland Pollinator Protection Plan
For more information on pollinator-friendly farm management practices, check out Delaware’s Farm Management for Native Bees
