Tuesday, April 12, 2016

Preventing Bird Damage in the Garden


Birds can devastate young vegetable seedlings or ruin fresh fruit in the blink of an eye but if we know what to do, and take action before they strike, we can often prevent problems.

Many of us are all too familiar with damage caused by birds to ripening apricots, plums, grapes, and other garden fruits.  We know it happens and even come to expect it.  However, few people realize that birds can also seriously damage vegetable gardens.  The fact is that yes, birds can make pests of themselves in vegetable gardens, particularly when young plants are in the seedling stage.   Some people would be quick to say that they can be very aggravating pests.  For those who know what I am talking about, I sense your frustration.

Birds can damage fruit and vegetables in two basic ways.  The most obvious is direct feeding and the other is contamination of food products.  Let’s consider some examples.

Horned larks are notorious in the commercial vegetable industry and in home vegetable gardens for nipping at new seedlings emerging from the ground.  They usually don’t really eat the plant.  Mostly  they just bite it, perhaps for a taste of the sap.  Sometimes though, they will pull it completely out of the ground.  In these cases, it is not uncommon to find the poor, abused seedling lying discarded nearby after this not too gentle treatment.  Horned larks are not the only ones that do this of course, but they are notorious for this kind of damage.

Other birds like finches, sparrows, thrashers, and wrens will peck holes in the soft flesh of ripening fruit.  Figs, apricots, peaches, and plums are common targets for birds. Woodpeckers and their relatives the sapsuckers, peck holes in the rinds of citrus fruit looking for a juicy taste of fresh fruit.  Many birds figure out how to hunt the seeds that you just put in the ground and have lunch at your expense. If you are growing your own grains, watch out for the red-winged blackbird.  They and their cronies will absolutely love your harvest.

Birds also cause damage to garden crops through direct contamination of the edible parts of the plant.  Bird droppings are usually not a problem when they fall on fruits that will be peeled, but when they end up on difficult to wash fruit like blackberries, strawberries, and clusters of table grapes, they make a real mess and the residues could harbor disease.

The sight of bird feces on fresh fruit is guaranteed to quickly destroy any desire one might have to pluck a ripe fruit and plop it directly in the mouth.  Even so, most produce can be cleansed with a careful washing.  In fact, it is a good idea to inspect food materials carefully before you place anything in your mouth.  Even if you can’t see any contamination, it is always good to wash before you eat.  It is better to be safe than sorry, I say.

How do we prevent bird problems in the garden?  When thinking about control, many people quickly jump to the idea of chemical poisons and repellents.  However, since most gardeners do not have the proper training, certification, and license to use chemicals to control birds, that way is out.  Don’t even think about it.  Put it out of your mind.  Don’t go there.

The same goes for shooting with fire arms, sling shots, or arrows.  There are a whole bunch of laws that if violated, could bring embarrassment, financial difficulties, and even imprisonment.  Unless you have legal permission, birds cannot be harmed in any way.  Just so we are clear, almost every bird you see is protected by state and/or federal regulations.  Killing or injuring birds without a license carries a stiff punishment and could get you into big trouble.  Don’t do it.

So, what can you do to protect your garden from the ravages of hungry birds?  There are a number of things that can be done and most fall within three categories: frightening devices, mechanical barriers, and habitat modification.

Okay, let me emphasize right here that I am not recommending the use of loud sounds in populated areas to frighten away birds.  While farmers out in the country might get away with propane cannons, fireworks, and blank shotgun blasts, no one in the city wants to wake up to a loud bang or pop at the crack of dawn.  Not only will the neighbors be upset, but the local law enforcement community also.  They take a dim view of such activities, even if it is in the name of good gardening, because there are laws against disturbing the public peace.

On the other hand, a good predator silhouette works very well to frighten birds away.  It is quiet and causes no harm to the animals.  Some people use hawks or snakes, but I like to use an owl.  Strategically placed and moved regularly, birds have a tough time telling the difference between a real owl and a plastic one in the few seconds they have to make a life or death decision.  I really like the plastic owl that, with power from a solar collector, is able to move its head. Any movement is good because it gives the birds a more realistic view.  I have seen birds literally do a u-turn in mid flight when they suddenly see what they think is a live owl hiding among the foliage of a fig or apricot fig.  Predator images seem to work equally well in vegetable gardens.

Mechanical barriers are another good way to keep birds away from sensitive plants.  Many people already use bird netting over citrus, apricots, grapes, and plums to protect their fruit.  Floating row covers, light spun fabric especially designed for agricultural use, or the netting you use on your fruit trees can be set up to keep birds away from tender vegetable plants until they are large enough that birds lose interest.  The floating row cover can be laid directly on top of the plants because they are light enough that they do not damage plants.  Netting can be laid on top of a pole framework to keep them off the plants.

The last way to prevent bird damage is to change the natural habitat around your garden. Modifying conditions to make the area less interesting to the birds will help prevent bird populations from becoming excessive. The fewer the birds, the less damage will be sustained. 

Of course, birds can travel some distance to a feeding area so habitat modification may have its limits, but anytime we can camouflage or make a feeding site less interesting the better off we will be.  Common modification techniques include removing roosting areas like trees and shrubs in the vicinity of the garden area, moving the bird bath and decorative bird houses to another part of the yard, and eliminating nearby resting areas.

Birds cause many types of damage in the garden.  While there are some things that we definitely should not do, there are steps that you and I can take to effectively prevent bird damage without harming protected species.

If you have questions, you can reach one of the Master Gardeners at the Cooperative Extension office, 820 E. Cottonwood Lane, Building C, in Casa Grande.  The telephone is (520) 836-5221, extension 204.

The University of Arizona is an equal opportunity, affirmative action institution.  The University does not discriminate on the basis of race, color, religion, sex, national origin, age, disability, veteran status, or sexual orientation in its programs and activities.

Rick Gibson
Extension Agent, Agriculture
University of Arizona Cooperative Extension