(by Kim Adelson) –
Since many of us are now welcoming the opportunity to work in our gardens, this month I’m focusing on an important strategy to make your outdoor space more of a haven for birds. You can make your yard more wildlife-friendly by providing food, water, and shelter; diminishing the chances of window strikes and the threat of predation; and eliminating toxins.
Toxins in yards come mainly from insecticides and herbicides. Every year North American homeowners spread more than 130 million pounds of pesticides— far more than farmers do; many are harmful to birds. Because many pesticides aren’t specific to one type of organism, they can also injure people and pets, with numerous neurological effects, asthma and allergies, cancer, and birth defects. The World Health Organization estimates that, globally, pesticides poison 3 million people each year, resulting in more than 200,000 deaths annually. Generally, insecticides are more toxic to people and birds than herbicides.
The alternative to pesticides is integrated pest management, a common-sense approach that involves:
- Preventing infestation problems by maintaining a healthy, unstressed garden
- Identifying and learning about garden pests
- (Using that knowledge to) remove the pests’ food and water supplies
- Trying to physically exclude those pests from the area
- Learning to embrace or at least tolerate harmless species
- Allowing a reasonable number of harmful pests
- Using the most benign pest control methods first, with toxic methods only if absolutely necessary
- Using targeted pesticides as sparingly as possible
Prevention: Happy, healthy plants are harder to infest and infect. Use compost to enrich your soil and mulch to discourage weeds and retain moisture. Leave three inches of lawn when you mow, and water less frequently but more deeply to encourage deep root growth which helps choke out weeds. Get rid of weeds before they go to seed and propagate, and cull sickly, diseased plants before their condition spreads. To avoid fungal infections, water early in the day so plants dry out before nightfall; similarly, water the ground around the plant rather than wetting the leaves. Best of all, go native, since well-placed native plants typically require little pesticide and are disease-resistant.
Physically exclude pests: Consider draping non-ornamental plants in fine netting material, to keep insects from eating them and laying eggs on them. Stymie grubs with collars of rolled plastic placed around your plants’ stems and pushed several inches into the dirt.
Remove food and water sources: This is generally more of a house issue than a yard one. Removing food and water supplies discourages noxious insects, but it also discourages desirable ones as well as birds.
Accept harmless species: Many insects are benign and even desirable, since they prey upon their more troublesome brethren and are important food for birds. Learn to identify wanted species and leave them be. (Better yet, make your yard welcoming to them: they’re not named slug-eating beetles and parasitic wasps for nothing!)
Accept a reasonable number of pests: Since we live in an area with lots of wild, undeveloped land, a stray thrip or two, some whiteflies, etc. are going to land on your property. Of course you don’t want them to unduly multiply, so nip the problem in the bud, so to speak, and remove them as you find them, but there is no need to over-react and start spraying everything in sight.
Instead . . .
Employ benign methods: There are so many! Knock insects off your plants with a hose or vacuum them off. Set out sticky traps. Bury a few coffee cans with their lips flush with the ground, so insects fall in and can’t crawl out; if you want to be fancy, put a piece of ripe fruit on the bottom to entice bugs. (More elaborate homemade traps that don’t harm beneficial insect are available, too.) Plant “trap plants” that destructive insects prefer to lure them away from other plants. (Think marigolds, sunflowers, zinnias, and nasturtiums for flower beds, and dill, mustard, chives, and basil in your gardens.) Numerous homemade solutions—made from boiled garlic, castile soap, Epsom salt, Tabasco, or Neem oil— make benign sprays to deter aphids, spiders, spidermites, and caterpillars. Slugs avoid crushed eggshells. Recipes can easily be found by doing a Web search.
Most native plants attract beneficial insects and birds that prey on pests. Put up bat houses: a single bat can eat up to 8,000 insects per night. Do all you can to attract birds: most eat insects, especially during the breeding season; even birds we generally consider seed-eaters offer their hatchlings a primarily insect diet. Prune away disease as soon as it appears, and be sure to wash the tools you used before they touch healthy plants. All my gardener friends in New Zealand—as a group, Kiwi gardens are more “picture perfect” than ours—prune out infestations, hose garden pests off their plants, and kill weeds in yards and sidewalk cracks with boiling water. It is a mark of shame to have to employ artificial chemicals.
Use targeted pesticides only as a last resort, and only products targeted to your pest. In general, non-insects are less likely to eat insecticides in bait traps with small openings than freely spread insecticides; granular formulations are especially attractive to birds. The most important insecticides to avoid, because of their toxicity: organochlorines (e.g., dicofol, methoxychlor), organophosphates (e.g. diazinon, isofenphos, chlorpyrifos), and carbamates (e.g. aldicarb, carbofuran, bendiocarb). [Neonictanoids, such as acetamiprid and chothianidn, are relatively safe for birds and mammals but kill pollinating bees.] Herbicides containing dinitrophenols, such as dinoseb or paraquat, are especially toxic to birds. No matter what product you use, avoid spraying on windy days, and never near a water source.
Healthy gardens attract and support bees, parasitic wasps, ground beetles, lacewings, and butterflies, which help plants by being pollinators or by consuming plant predators. They are high in fat and protein and provide much needed food for birds. The goal is not to have a bug-free garden, but one with a thriving community of beneficial, useful insects. This will in turn attract birds. Please avoid using harmful chemicals: there are alternative strategies, and your yard and the birds we love will thank you. (by Kim Adelson)