How many times have you seen a bee in your garden, buzzing from one snapdragon or squash blossom to another? At each visit the bee almost disappears into the flower as it uses its long tongue to lap nectar hidden deep within the flower. When it backs out, tiny bits of pollen are stuck to the hind legs and hairy body.  You are witnessing the remarkable act of pollination. The honeybee is the most important carrier of pollen.

Pollinators, such as honeybees, birds, bats and insects, play a crucial role in flowering plant reproduction and in the production of most fruits and vegetables. Without the assistance of pollinators, most plants cannot reproduce.  In fact, over 90 percent of all flowering plants and over three-fourths of the staple crop plants that feed humans rely on pollinators.

Gardeners can do many things to protect garden pollinators. Bees are the world's workhorse pollinators. They visit hundreds of flowers in one day searching for nectar and pollen. While honeybees are the best known bees, most pollination is actually done by wild solitary bees such as bumblebees, leafcutter bees and ground bees. Bees and wasps are also predators of pest insects.

Butterflies are some of the world's most beautiful pollinators. Butterflies seek out gardens that not only provide nectar, but plants for food during the caterpillar stage. Flies pollinate a huge variety of flowers, including many common garden flowers. Syrphid fly (Syrphidae spp.) is particularly common in the spring and fall.

Moths are less showy than butterflies, but even more numerous. They are most active at night and are attracted to white or light colored flowers with a strong sweet scent. Hummingbirds consume 50 percent of their weight in nectar a day. Hummers use their long beaks and tongues to gather nectar and pollen that collects on their foreheads. Bats are found along the Front Range and they feast on nectar, eat the fruit of those same plants and help disperse the seeds of arid cacti and desert plants.

Pollinators keep the ecosystem running. They need protection from excessive exposure to pesticides and other chemicals that can poison them or impair their reproduction. Being safe and sane when using pesticides in the garden is vital. All pollinators and beneficial insects are super sensitive to insecticides and some to herbicides.

Some options for getting rid of bugs without resorting to high-powered insecticides include using the hose to wash the insects off. Insecticidal soaps will help control the aphids, mites, young scales, whiteflies, psyllids, and mealybugs if the soap hits the bodies of the insects directly.

Bt (Bacillus thuringiensis) is a safe product to use on leaf- and needle-feeding caterpillars. The insect ingests Bt and develops a bacterial disease that kills it within a few days. It is not harmful to people, pets or to birds. Pollination is not a free service. Investment and stewardship are required to protect and sustain it.

For more information, see Fact Sheet #7.002 Pollination of Tree Fruits, #5.525 Wasps and Bees in the Home, #5.504 Attracting Butterflies to the Garden,  #5.550 Beneficial Insects and Other Arthropods, #5.547 Insect Control: Soaps and Detergents, #5.556 Bacillus thuringiensis, and #2.945 Friendly Pesticides for Home Gardens.

Q:  The tips of the branches on some of my aspen have turned black and are curling over to look almost like a "shepherd's crook".  The leaves are distorted and have turned brown black. What is causing this and what should I be doing for it?

A:  This is probably a fungal disease called "aspen/poplar shoot blight".  It affects primarily aspens, cottonwoods and poplars.  The fungus spreads down through the new growth at the tips of the branches killing the new shoots and causing the growth to be distorted.  Moisture and high humidity are factors in the spread of shoot blight.  The fungus over-winters as spores on dead leaves and twigs and can re-infect new growth in the spring.  It's important in the fall to rake up and destroy diseased leaves and branches to help prevent the spread of the spores to new spring growth.

Q: I understand that there are some raspberries that bear fruit in the summer and others that fruit in the fall.  Do raspberries need to be pruned to get better fruit production and if so, how and when?

A: There are two types of red raspberries: summer-bearing and fall-bearing.  Summer-bearing varieties produce fruit in the summer on canes from the previous year. They should be mowed to the ground after they have produced fruit.  Dispose of the canes as they can harbor insects and disease.  Mow the canes of fall-bearing raspberries to the ground as soon as they have finished bearing in the fall.

Q: The tops of some of my raspberry canes have just suddenly drooped over and begun wilting.  Is this some sort of insect or disease?

A: This is most likely raspberry cane borers.  The white larvae of these borers burrow down into the cane and kill it.  Rapid action is important.  Remove the infected canes when you first notice signs of infection.  To control, apply Sevin or another labeled insecticide, according to directions, before blossoms open.

Have a great time and stock up on fresh Colorado produce at the following farmers' markets:
1) Saturday mornings 8 a.m. to 12 noon, Remington and Oak, July 12-October 4,
2) Thursday evenings 5-8:30 p.m. Laporte Avenue between Howes and Mason,  July17 - August 21 and
3) Wednesdays 2-6 p.m. and Sundays 11 a.m. - 3 p.m. southwest corner of Harmony and Lemay through October 28.

This is the time to fertilize warm season grasses like buffalo grass and blue gramma.  Use 1/2 to 1 lb. of nitrogen per 1000 sq. ft.

"Knee high by the 4th of July."  Maybe not, but you should fertilize your corn when it does get that tall.  Use 1/4 lb. of nitrogen per 100 sq. ft.

The authors have received training through Colorado State University Cooperative Extension's Master Gardener program and is a Master Gardener volunteer for Larimer County.

Gardening and Insect Fact Sheets are available on-line by clicking HERE.

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This page updated:  July 14, 2003