Holey trees! Sure sign of woodpeckers

For those horticulturally inclined, life is never boring. We enjoy the beauty of plants and flowers. We are fascinated and tormented by insects and critters. Often we are intrigued by some horticultural mystery. Last week Barbara brought in pictures of a pine tree riddled with holes. My immediate response was woodpeckers; until in one photo, I saw an unfamiliar series of holes. I sent the photos on to Wendy Hanson, who answers horticulture questions for University of Nevada Cooperative Extension in four counties.

Wendy responded, "Woodpeckers, but they really were going after something in that tree - searching and digging repeatedly!" Woodpeckers include flickers and sapsuckers. Most woodpeckers feed on tree-living or wood-boring insects. Some feed on ground insects such as ants. Sapsuckers feed extensively on tree sap as well as insects, and are infamous for drilling holes in parallel rows around a trunk.

Woodpeckers pound on trees, houses, utility poles and other wood and metal objects not always seeking food, but sometimes "drumming" to establish territory and to signal mates. This rapid rhythmic pecking is annoying and can damage houses and structures and, as the photos show, injure trees as well.

The reason the holes were so large in the second photo was probably due to repeated pecking in search of food, although limb growth can also expand the holes. In some instances, the holes can girdle the tree or a limb and kill the tree. In forested areas, this damage can attract more insects, including borers, and sometimes porcupines and squirrels.

Woodpeckers are protected by the Federal Migratory Bird Treaty Act and shouldn't be killed. Excluding them with netting or metal barriers is one method of control. Don't bother with stationary model hawks, owls or snakes. Large rubber balloons with owl-like eyes painted on might frighten the birds away. Pinwheels that move in the wind can deter woodpeckers. Some success has been achieved with hanging round magnifying type mirrors in the drumming area. Loud noises, if repeated whenever the bird first comes into the area, can harass the bird away.

All these remedies have to be used as soon as the bird comes into the territory, before territories are well established. Certain sticky substances such as Tanglefoot, 4-the-Birds or Roost-No-More, placed where the sapsuckers are working, discourage the birds without entrapping them. These products may discolor painted, stained or natural surfaces and may run in hot weather causing ugly streaks.

For detailed information on managing woodpeckers e-mail skellyj@unce.unr.edu or call 887-2252.

• JoAnne Skelly is the Carson City/Storey County Extension educator for University of Nevada Cooperative Extension and may be reached at skellyj@unce.unr.edu or 887-2252.