L'Association pour la santé environnementale du Québec / Environmental Health Association of Québec

How to Manage – Pesticide-free

Bug-Free Naturally

Laurel Maloney, B.Sc. Entomologist

Using pesticides of any kind to kill off insects, such as sow-bugs, millipedes, silverfish or carpenter ants that have invaded your living space is much like using perfume to remedy a garbage spill. It may show immediate results but it is by no means a permanent fix.

The reason is that unwanted pests in your home are usually a sign of structural deficiencies and until these deficiencies are addressed, the pest problem will keep coming back!

Back when city by-laws were first being enacted to protect people from pesticides, Paul Maloney, my father, and the original Eco Bug Doctor, got a memorable call at our office.

Pest problems can be solved without using pesticides, by repairing leaky plumbing and other structural deficiencies.

A woman, a medical doctor in fact, was upset by the fact that she was not allowed to use pesticides to get rid of the carpenter ants around the doorway of her home. Paul assured her that he could help the ant situation and although she was skeptical that a ‘soft’ ecological approach would have an effect, she agreed to a home visit.

An inspection of the ant-infested area revealed that water was seeping into the bottom of the wooden door frame, creating the perfect living environment for these wood-recycling ants. By finding the source of the problem, Paul was able to solve the problem, without the use of potentially harmful chemicals. The doctor was so impressed by the results, she started promoting an ecological approach to pest control herself, referring many friends and colleagues to us.

Water is the substance from which all life arises, but if you add water to a solid wood structure, over time the wood begins to break down, releasing nutrients that allow mould (fungi) to grow. This in turn attracts detritivores (sow-bugs, millipedes, and silverfish), the insects and other small creatures that feed on decomposing matter. Then, to complete the ecosystem, the predators move in, the centipedes and spiders that feed on the detritivores, just like wolves hunting rabbits. If you protect this wood from water infiltration and dry out the area, you will put an end to this miniature ‘ecosystem’ and permanently solve the moisture-bug problems in your house.

There’s another positive side-effect to this ‘ecological’ approach to ridding the home of pests; it may also rid the home of mould, which like man-made toxic chemicals, can trigger a host of symptoms, discomfort and health problems, including allergic reactions, asthma symptoms, irritant effects, headaches, respiratory problems and problems concentrating.

There is also good evidence that mycotoxins can be carcinogens, immune suppressants and neurotoxic agents.

According to Dr. Schaller, author of many books on mould and illness, the most common cause of learning disorders and behavioral problems in children and adolescents that he has treated has been indoor mould contaminants.

Mould is usually not visible to the naked eye, and doesn’t always smell, although we are all familiar with its musty smell. Washington’s Institute of Medicine, a non-profit advisory group, affirms what we have been telling clients for years: in order to prevent mould and associated creatures (such as sow-bugs) in a building you must keep materials dry, or use building materials that offer a poor substrate for growth in places where moisture is unavoidable. Though the task may seem daunting, with a bit of creativity, lower-cost solutions can be found to address a whole host of structural deficiencies.

Pesticides – Use Only Alternatives to Pesticides

Prevention tips: Keep the house clean, especially the kitchen and bathroom. Empty garbage cans every day. Store food in containers with fitting lids. Do not leave overripe fruit on the counter. Repair leaks to avoid moisture problems. Fill holes and cracks to prevent insects from entering. Remove any firewood and tree branches in contact with the house.

AntsMix 1 litre of water, 7 teaspoons of boric acid (available at most drug stores) and 1 cup of sugar. Soak cotton balls in the solution, then place them into an old margarine container with the lid on. Punch holes in the sides of the container to allow the ants to get in, and place the ‘bait stations’ wherever you have seen ants. If ants are very tiny, omit the container—keep cotton balls away from children and pets. Moisten cotton balls daily. After one or two weeks, make a new solution with only half the amount of boric acid. Use fresh cotton balls. Refill stations. A good portion of the ant colony will be killed with the first solution. But it is the weaker solution that will give you long term control as the ants continue to feed the colony with boric acid. It is important to allow the ants to take the solution back to the nest. Resist the temptation to stomp any ants that you see.
FleasAdd 1 to 2 tablespoons of nutritional yeast (available in health food stores) to your cat or dog’s food to prevent fleas. Frequently wash or vacuum all pet bedding, remembering to empty the vacuum cleaner bag after each cleaning session.

A Beautiful Lawn, Chemical-Free

Édith Smeesters

Is it possible to have a beautiful lawn without using chemical products? Of course, but… this all depends on your expectations and the work that you are willing to invest!

The current situation

Ever since Québec implemented its Pesticide Management Code in 2003, and especially after its 2006 implementation in the residential sector, it is no longer permitted to use most pesticides on lawns of the “Belle Province,” in particular, the selective herbicides that allowed us to instantly eliminate dandelions and other broad-leaved plants. Unfortunately, for many people, a beautiful lawn is a uniform lawn, without dandelions, since this is what the media has been advertising for at least 4 decades. So, unless we wish to spend our time pulling the dandelions out by hand, this seems an almost impossible objective without herbicides. But we should not have to resort to applying chemical products in order to have beautiful grass!

The ecological lawn

A nice, lush lawn has some undeniable qualities: it can rapidly stabilize the soil, fix CO2, buffer against shock, reduce the temperature (compared to paved surfaces), make a great surface for playing and increase the value of other aspects of the landscape, like a display case of greenery. But if the use of polluting products and large quantities of water are needed to obtain this, this is obviously not a healthy option. Luckily, it is possible to obtain the same benefits using ecological methods and products.

In fact, there are different types of ecological lawns. We can have an impeccable lawn if it is installed on soil that has been well prepared, using the cultural methods that we will discuss below, and by the exclusive use of natural fertilizers and low-impact pesticides when needed. But, let’s be realistic; this sort of lawn will require a lot of products, work and money, as well as regular irrigation in case of drought. In other words, it is much like the lawn maintained with chemical products. However, you can drastically reduce the effort required if you opt for a low-maintenance grass species, or if you become more tolerant of the native plant species that naturally move in to colonize green spaces. Besides, who says that a beautiful lawn should consist exclusively of graminates? Isn’t the objective to have a lush, green lawn? And if this is possible with less effort, where is the problem?

The prestigious lawn

A beautiful lawn is most important in front of the house, and easiest to obtain if your property is not overly large. There are a few basic methods that can be applied to obtain the desired results, just like in the cultivation of orchids or of prolific tomato plants.

Aerate the soil

Even though most grass species are quite resistant to being stepped on, they still require a minimum amount of air at the level of the roots, especially with a very dense soil, and where they are subjected to heavy traffic. When the soil is compacted, air spaces are squished and the grass roots can no longer penetrate deep into the soil, which makes the lawn more susceptible to drought. Aeration allows for better penetration of water and fertilizer into the soil, and promotes greater activity of organisms that decompose thatch in the soil.

The compaction of the soil can be measure by sinking a wood pencil into the earth. If you need to force the pencil to sink up to around 10cm, then it is necessary to aerate the soil. Preferably, you can rent a motorized aerator that removes plugs of soil from the lawn, leaving these to disintegrate at the soil surface. This should be done when the grass is growing vigorously, in the springtime or towards the end of summer.

Compost: the key to success!

Spread a fine layer of compost over the lawn, ideally after aeration, though composting alone is already very beneficial. This stimulates the microorganisms and improves soil structure, promoting deeper penetration of the grass roots into the soil. The soil will become more porous and will better retain water and nutrients. Regular application of compost is a good way to solve minor problems of soil compaction and thatch. Apply about 0.25 to 0.50 cm of compost (or around 1.5 to 1 kg of compost per 100 m2), once a year, on grass that has been cut short. It is preferable to use a sifted, commercial compost, as the household compost can contain undesirable seeds. Apply the compost evenly, by the shovel-full, taking care to later redress grass strands, using a rake. Though it is a rather demanding exercise, it is worth its weight in gold, and can be expedited by the rental of a granule spreader, available in some gardening centers. Many professionals even use motorized spreaders for applying over larger areas

Do not dethatch

At the first snowmelt, many people are inclined to attack their lawn with a de-thatching rake. This practice is actually as hard on the back as it is on the lawn, especially on ground that is still spongy, since this pulls out as much healthy grass as it does thatch. A better plan would be to gently rake the lawn in the spring. In fact, we often confuse the dead grass from over the winter, which will shortly disappear on its own, with thatch. Thatch is composed of a layer of dead rhizomes that accumulate under healthy grass. A thin layer of thatch (0.5 to 1.5cm) is normal for a lawn, and can even be beneficial as it nourishes organisms that help with decomposition, retains water, and protects the lawn against drought. However, if there is too much thatch (over 1.5cm), the grass will tend to take root in this layer rather than in the soil, which makes the lawn more susceptible to drying out and disease. Furthermore, excess thatch can also provide shelter to a number of parasites. In this case, dethatching is necessary, or, even better, apply a spread of compost.

Most importantly, the formation of excess thatch can be prevented by avoiding large doses of fertilizer, which accelerate the growth of the grass (and of thatch!) and by banishing the insecticides that can kill off beneficial organisms, such as the detritivores.

Cut the grass high!

All the specialists agree that mowing the grass high plays a major role in determining the beauty and health of the lawn. We can never overemphasize it: it is necessary to mow the grass high, leaving at least 8cm, and even up to 10cm during a particularly warm spell.

By mowing the grass high, you make it more resistant to drought, since the roots will also grow deeper. You will save on fertilizer, as the grass will have more opportunity to photosynthesize and will naturally be more vigorous. On top of this, you will also be reducing the germination of weeds, which prefer the light provided by short grass.

The first and last mowing can be shorter (5cm), in order to encourage the growth of lateral shoots (in the springtime) or to prevent overly long grass from being flattened to the ground during winter, which can promote disease in the following spring.

Recycle lawn clippings on site

Not only is it unnecessary to pick up grass clippings, but it is actually better for the lawn to leave these clippings on the ground. You will save at least 30% on fertilizer, diminish the apparition of potential diseases, protect the soil from drought, and nourish the beneficial organisms in the soil. The accumulation of thatch has nothing to do with whether or not you leave grass clippings in place. Also, you will reduce the volume of your wastes considerably and you will save time by not having to constantly empty the bags on your mower. It is obviously preferable to be equipped with a mower that can pulverize the clippings, or to add supplementary equipment to the mower that you already have. Consult the manufacturer for mower details.

Do you need to apply fertilizer?

Yes, if you have a lawn that consists mainly of high-maintenance graminates like Smooth Meadow-grass or Kentucky Bluegrass. Most grass seed mixes and sheet grasses consist mainly of this species. Agronomists recommend applying 1 to 2 kg of nitrogen per year, on a lawn of 100 m2 where Kentucky Bluegrass makes up a major part of the mix. With natural fertilizers, which stimulate the natural mechanisms of fertility, specialists recommend applying between 0.5 and 1.5kg of nitrogen per 100 m2. However, if you do not pick up grass clippings after mowing, and if you also apply compost, you can reduce at least 1kg of nitrogen per 100 m2, meaning you hardly need to apply any fertilizer at all! As natural fertilizers are not very soluble, you can get away with a single application per year, in spring or in autumn. And since natural fertilizers break down slowly, with the assistance of soil microorganisms, their effect is slower than with chemical fertilizers. Be patient! If you have an abundance of clover in your lawn, skip the fertilizer completely, because this plant fixes nitrogen and will, in this manner, help the surrounding graminates.

And for watering?

To stay green all summer, a traditional lawn requires a good watering about once a week, depending on temperatures. Unfortunately, even if Québec owns 3% of the world reserves of fresh water, this water is neither free nor abundant from the tap or otherwise, especially during a heat wave. The approach that I recommend is to cut the grass high and water the lawn when it is allowed, in order to promote deep penetration of grass roots. The application of compost at least once a year will also help promote longer water retention. But keep in mind that there are many species that are more resistant to drought than Kentucky Bluegrass, (I will come back to this a little later), and that do not die during a heat wave but simply fall into a period of dormancy. So, no need for worry.


It is essential to over-seed in order to keep your lawn lush and to prevent the sprouting of undesirable plants. All patches of bare earth on your lawn make excellent harboring spots for opportunistic plants to move in. Cover your new seeds with a bit of compost, and keep the surface humid up until germination. Most grass seed mixes contain essentially 3 varieties: Kentucky Bluegrass (sun-loving plant), Creeping Red Fescue (semi-shade species), and Ray-grass, which germinates rapidly, protecting the soil in waiting for the germination of the other two species. With good sunlight, the bluegrass will rapidly dominate, thus necessitating constant care: fertilizer, watering, etc. But why not introduce some low-maintenance species into the mix, to make life easier?

Low-maintenance lawns

We can now find some low-maintenance mixes on the market. These are mixes that contain species that will require less or no fertilizer at all, grow slower, are more tolerant to drought, and some that are even resistant to insects. For example, Chewing Fescue and Hard Fescue contain endophytic fungi which make them unpalatable to the chinch bug or to the sod webworm. These same insects will not feed on white clover either, and this leguminous plant doesn’t need any fertilizer since it fixes nitrogen from the air, a fact that can be well appreciated, especially by those who live by a lake or running water, where fertilizers are often banned. The fescues and clover are, however, less resistant to being stepped on than bluegrass or ryegrass, which is why it is best not to eliminate all of our grass mixes. Also, there are some bluegrass varieties that are less demanding for fertilizer and more resistant to drought.

And White Grubs?

In the greater area of Montreal, white grub (European chafer) infestations are still decimating lawns, and there are, unfortunately, no grass species resistant to these voracious larvae that can also feed on other plants. But it has been found that the problem is much less severe on lawns that are lush and vigorous, and cut high. European chafers prefer to lay eggs on short grass and the ravages are worse and more evident on lawns already weakened by other stresses: dry soil, sandy slopes, or a lawn weakened by disease, or other factors. These beetles are also attracted by nighttime lights. Turn off your exterior lights during the egg-laying period: in the month of July. In a grub-ravaged lawn, over-seed quickly in the month of May, when the larvae stop feeding and will soon emerge as adults. You have until the end of July to freshen-up your lawn and prepare for the next assault!

A bit of tolerance…and less work

As you can see, it is not all that complicated to have an ecological lawn. In fact, the principles are the same for the maintenance of a conventional lawn, minus the pesticides and fertilizers of course! The more vigorous the lawn, the less problems you will have with infestations. But the greatest difference is that, with an ecological lawn, you have much greater biodiversity. A truly ecological lawn cannot contain just one species, as this would be contrary to all the laws of

nature. Monocultures promote infestations, because insects encounter few predators to keep them in check. It’s the biodiversity that attracts these predators into a natural environment, because each plant attracts a different insect, and this creates an equilibrium where no one insect can dominate the others. So, try to be tolerant to the wild plants that appear on your lawn, and you will have much less work and stress. And if you follow the advice here, you will obtain a lush lawn, where dandelions are rare and will practically disappear after flowering. Run the lawn-mower a bit more often during the month of May, and use the bag only once, to discourage seeds from spreading. This only lasts for 2 weeks, and are there not plenty of better things to do than fight these flowers?

Reduce the size of your lawn!

All the positive qualities of a lawn, mentioned above, apply to other plants as well, if not even more, as mowing generates much noise and pollution. So, the CO2 absorbed by these lawns is rapidly annulled by the burning of fossil fuels! Mature trees are able to purify much more air, in the same area of land, and provide shade at the same time. Spreads of perennials or groundcovers are better for conserving water and better at retaining soil along natural river sides, and are much better at filtering pollutants and fertilizers.

But, rest assured, I will not recommend that you get rid of your lawn. It has its qualities and is more resistant to being stepped on than any other type of groundcover, but you can, perhaps, reduce its surface, as there are many ecological and economical ways of designing your property layout.