Utah Pests News Fall 2009

click here for pdf version


While the UPPDL is currently without a plant disease diagnostician, we are keeping up with the many disease samples with help from the Oregon State University Plant Clinic.  With the wet spring this year, turf diseases have been especially prevalent, including gray and pink snow molds and take-all patch (Click orange links for fact sheets.)

To prevent diseases next spring, take action this fall.  Aerate your lawn, mow to 1-1.5 inches, and remove grass clippings for the final cut of the year.


Diane Alston 
Entomology Specialist  

Ryan Davis
Insect Diagnostician 

Marion Murray
IPM Project Leader 
Editor, Utah Pests News

Utah Plant Pest Diagnostic Lab
BNR Room 203
Utah State University
5305 Old Main Hill
Logan, UT 84322

Utah Pests News is published quarterly by the UTAH PESTS staff. 





Additional articles in this issue:

Ash and Elm Yellows in Utah

Raspberry Horntail Severe in 2009

UPPDL Insect Scouting Results

News, Publications, Web sites


Birds and Bats for Alternative Pest Management

Some bird and bat species can be useful allies in running a successful IPM program.  They are motivated, efficient, and cost-effective pest predators.  Foraging by birds or bats alone will not completely prevent pest injury, but in a healthy landscape or farm, they can play an important role.  There are ways to manage or manipulate your garden or farm to attract the best and hungriest workhorses.


Birds of prey feed on small mammals (mice, gophers), birds, and large insects.  The kestrel (above) is a small hawk that has long been used in some Utah fruit orchards for seasonal mice control.  The McMullin Orchard in Santaquin has maintained kestrel boxes for over 10 years.  They find that kestrels return year after year to the boxes, but are highly territorial, so the McMullins only use about 6-8 boxes per 400 acres.  The McMullins monitor the boxes for starlings, and remove their nests.  Claude Rowley of Cherry Hill Farms built and installed a box this summer on his 250-acre Goshen farm.  The box remained empty until mid-summer, when he decided to add some nesting material of dried sticks and twigs.  Five days later, a pair moved in that eventually fledged four young.  Rowley is impressed with the mouse control, and says that so far, the only place they can find mice is in the highest pressure area, although he has yet to see the full effects until after they mow this fall.  He will be adding more boxes in Goshen as well as on other family farms.

Barn owls (found in limited numbers in Utah) feed on large rodents and birds, and their number one choice of prey is gophers.  They can be of great value in all agricultural situations, but their population is dwindling due to lack of nesting sites.

To attract birds of prey:

  • kestrels:  Screw nesting boxes to power poles or trees 10-20 feet above ground, away from human activity (shown above). Install up to 1 box per 5 acres to increase chances of nesting, but note that a pair may defend up to 250 acres. Adding a bit of nesting material (twigs, wood shavings) can help attract the birds. Monitor each box weekly and remove starling nests. (Watch for starlings moving in and out of the box.  A starling nest will fill the cavity floor, with a deep bowl in the back and material up the sides. Eggs are blue like robins’.) Clean the boxes each year.
  • barn owls:  To attract/keep birds on the farm, do not destroy old wooden barns; barn owls will not nest in metal barns. Nest boxes can be used in place of cavity trees or abandoned buildings. Owls may patrol up to 200 acres per nesting site.
  • Install hawk perches at least 8 feet off the ground; one grower in Utah attached posts to his irrigation risers and they are often used by hawks.



Some of the most common and hard-working are:

  • bluebirds – eat large numbers of a variety of insects including grasshoppers; nest in boxes or cavities.
  • chickadees (shown above) - eat more insects per bird (up to 900/day) than any other, including scale, aphid, leafhoppers; nest in boxes or cavities.
  • robins – primarily eat insects in spring when raising young; nest in trees.
  • swallows – eat flying insects including mosquitoes; variety of nesting sites.
  • woodpeckers – eat borers, bark beetles, and overwintering codling moths; feed by extending their long tongue into tight crevices; cavity nester.
  • wrens - eat grasshoppers, slugs, others; nest in a variety of places.

In orchards (particularly organic), birds such as juncos, flycatchers, swallows, and sparrows have shown to help regulate codling moth densities by feeding on diapausing larvae. A study of a California apple orchard showed up to 83% predation of codling moth larvae by birds during the winter (Baumgartner 2000). Insectivorous birds are most successful in organic orchards. To attract and keep birds in larger orchards, maintain diverse habitats (border planting mixes, alternate row plantings), leave a few older apple trees or large dead limbs for cavity nesters, and provide water and nesting boxes.

Cropland bordering woodland, shelterbelts, or riparian areas will also see benefits of bird predation, as birds will feed far into the field when prey is available (Puckett et al 2009). In research conducted in Ohio, red-winged blackbirds were shown to consume large quantities of corn earworm and other corn pests (Bollinger and Caslick 1985).

To attract insectivorous birds to your property:

  • place birdhouses and nesting boxes throughout; monitor all boxes weekly during the nesting season and remove competitive nests such as starlings or house sparrows, and leave bluebirds, house wrens, chickadees, and tree swallows; clean out the boxes each year.
  • provide nesting materials including small pieces of string, dryer lint, twigs, and shavings at various locations.
  • keep at least two sources of water filled throughout the year, one raised and one that sits on the ground.
  • plant a variety of trees and shrubs including those that provide nuts, berries, and seeds.


Poultry in the farm or garden has many benefits beyond providing food. They eat insects, snakes, and rodents, and provide fertilizer. 

Guinea fowl work best within a vegetable garden because they can be trained to eat only insects or other creatures and avoid the produce. They have keen eyesight, easily spotting prey from a distance. They are not suitable for small neighborhood lots because they have a very loud, distinctive call against intruders or other alarms. For farms, though, they are tough, disease-free birds, continuously on the move in search of food. They will also eat weed seeds, and their droppings make excellent fertilizer.

Layer chickens are quieter, and more suited for smaller farms. They eat voraciously, including grasshoppers, flies, ants, grubs, and weeds, providing good fertilizer. They are not compatible with a vegetable garden, especially with young plants and when food is nearing harvest. They scratch the earth endlessly, and will peck at plants and produce. But they are useful in “neutral” areas, or for cleaning up a garden after harvest, “tilling” the garden in spring, or fertilizing/weeding fallow beds. Some organic farmers use poultry and geese in their orchards to keep insect and weed populations at tolerable levels.


Bats can be an important component of an IPM program because they are the only night flying predator that targets moths. Not all bats can be attracted to the farm. Of the Utah bat species, the big brown bat is the most common that is adaptable to farmland or cities. An established colony feeds by the millions on larger insects. The little brown bat (locally abundant) also adapts to farmland, and feeds on flies (including mosquitoes), moths, mayflies, beetles, and leafhoppers. A single little brown bat can catch 600 mosquitoes per hour.

The Natural Resources Conservation Service runs an environmental quality incentives program (EQIP), and has provided funds to establish bat colonies. According to the program, an organic farmer in western Oregon was able to establish several bat colonies, and as a result, reduced his pesticide use for corn earworm from 13 to two applications per season.

Bat houses should be installed against buildings where they stay warm at night.  After installation, bats may take several years to find the houses.  Bat houses can be purchased from many farm and garden supply catalogues.

There is research underway looking at the use of bats to manage codling moths. A UC-Davis farm advisor is trapping bats in orchards and using DNA testing of the guano for evaluation of codling moth presence. Bats are generalist feeders, but where pest populations are high, they are likely to target that insect. Previous UC-Davis studies showed that moths comprise up to 70% of the diet of bats (Long 1996).

-Marion Murray, IPM Project Leader

Baumgartner, JoAnn. 2001. Birds, Spiders Naturally Control Codling Moths. Tree Fruit Magazine, April 2001. pp 5-7.
Bollinger, E.K, and Caslick, J.W. 1985. Red-wing blackbird predation on northern corn rootworm beetles in field corn. J. Appl. Ecol. 22: 39-48.
Long, Rachel. 1996. Bats for Insect Biocontrol in Agriculture. The IPM Practitioner: 18 (9): 1-6.
Puckett, H.L., et al. 2009. Avian foraging patterns in crop field edges adjacent to woody habitat. Agriculture, Ecosystems & Environment 131 (1): 15

Click the following orange links for more information:
kestrel boxes and use (pdf, see page 4)
barn owl info and nesting box plans
• an
overview of using poultry in sustainable systems
• “
Bat houses for Integrated Pest Management: Benefits for Organic Farmers, Final Report”
Bat Conservation International, with houses to purchase, or a plan to build your own 

Featured Picture of the Quarter

Most cicadas insert their eggs into living or dead twigs of trees and shrubs.  Smaller twigs with cicada eggs may be killed.  Shown at left are cicada eggs inside a currant cane.  Upon hatching, nymphs drop to the ground and burrow into the soil.  There they feed on the sap of plant roots, and depending on the species, will emerge as adults 2-17 years later.  The cicada song, produced only by the males, is the loudest in the insect world.

-Photo by Sharlyn Richards
(former student employee of Diane Alston)