This product is corn-gluten based, and it is not meant to work on weeds which are already growing, but on those which have yet to emerge (pre-emergent). Corn gluten meal has been promoted as an environmentally safer alternative to conventional herbicides, but there are still certain issues that bear considering. Research at Oregon State University showed that corn gluten meal did not prevent weed seed germination. Here is an excerpt from the study's findings:
"Corn gluten meal did not control any weeds in any trials under any circumstances over a two-year period. They found no evidence of pre- or post-emergence weed control in any of their trials. Because it contains 10 percent nitrogen, corn gluten meal proved to be a very effective fertilizer, causing lush, dense growth of turfgrass and of weeds in shrub beds."

Although corn gluten meal presents far fewer risks to human and animal health than conventional herbicide, a gardener who is attempting to use only organic methods might consider the source of the corn in these products, which is very likely to be genetically modified. This article from University of Wisconsin Master Gardeners addresses this question (note that the other information in the article pre-dates the research suggesting the nitrogen in corn gluten may actually enhance weed and other plant growth):
"Up to 60% of the commercial corn and soybeans in the United States is grown from GMO seed. Corn gluten sold as a preemergent herbicide may indeed contain GMO corn, but it has not yet been tested. Here's the twist. Corn gluten can reduce the need for traditional herbicides that have environmental side effects. It likely now contains GMO corn. It could be produced from non-GMO corn, but would likely be more expensive."

Washington State University professor of horticulture Linda Chalker-Scott has also written about "The Myth of Weed-Killing Gluten," and states that no research suggests this is an effective method of weed control in the Northwest. She recommends sub-irrigation, mulch, and soil solarization instead.

Season All Season
Date 2007-12-06
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Regarding your questions about lawn renovation, I have found a few options for you:

1. If the weed-and-feed product is for pre-emergent weeds, this would not work on your lawn, which already has dandelions growing actively. If the product is post-emergent, it will kill the dandelions, but if you are planning to sow grass seed, you will need to wait before sowing (different products have different guidelines, so check the directions on the package carefully). According to The Lawn Bible (by David R. Mellor, 2003), you should also make sure that the herbicide will target the weeds you have. Do not spray in windy conditions, and only treat areas which need it.

Overuse of herbicide destroys valuable bacteria and insects in the soil, so prevention is the best: mow the lawn high, which will keep weeds from getting established, as they need light to thrive; don't scalp the lawn; water only when it is too difficult to press a screwdriver into the top 2 inches of the soil.

2. There are less toxic alternatives. Some sources say that corn gluten prevents weed seeds from sprouting. They must be wet to be activated. (It won't work on dandelions which are already thriving in your lawn.) There is a product called Organic Weed Stopper Plus Corn Gluten Meal (from Walt's Organic Fertilizer Company in Seattle) which can be used: they recommend March 15 for getting rid of crabgrass, and August 15 for fall dandelions. (Please note that subsequent research suggests corn gluten may be ineffective as a weed control method. See this Oregon State University study.)

According to Ann Lovejoy's book, The Handbook of Northwest Gardening, corn gluten should be spread at a rate of 20 pounds per 1,000 square feet of lawn. Do this two or three times a year (in spring and fall, with a summer booster as needed). For ongoing weed suppression, apply it in small amounts whenever you pull up weeds (make a paste of corn gluten and water).

3. The Lovejoy book also has a recipe for fall lawn renovation:
a. Mow the existing grass as short as possible.
b. Spread 1 inch of clean crushed quarter-ten gravel (not pea gravel) evenly over the entire surface.
c. Spread 1 inch of compost over the gravel.
d. Top-seed with a regionally appropriate blend if the lawn is thin and spotty.
e. Wait 6-7 weeks before mowing again.

A criticism of weed-and-feed products is that they will add excessive amounts of phosphorus to your lawn, which will actually encourage weed growth once the herbicide breaks down.

Seattle Public Utilities has good information about controlling dandelions without using weed-and-feed products.

(See also the 6 Steps of Natural Lawn Care in the left-hand menu.)

And, Washington Toxics Coalition has information on an overall approach to lawn care

Season All Season
Date 2007-12-06
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Comfrey (Symphytum officinale) has a fibrous root system which is very deep and difficult to eradicate. Any bits of root left in the soil can produce new plants. While it may be tempting to take the quick path and use RoundUp to get rid of your comfrey, you may want to consider the health and environmental consequences of this product, whose active ingredient is glyphosate. Northwest Coalition for Alternatives to Pesticides has information about this chemical.

If you avoid using herbicide, you may find additional uses in the garden for the comfrey you remove by hand. Do not rototill this plant, and always wear gloves when handling it. Dig carefully and remove as much as you can of the roots, and then dispose of them. Pacific Northwest gardener and author Mary Preus writes about comfrey in The Northwest Herb Lover’s Handbook (Sasquatch Books, 2000):

Comfrey can play an important role in compost making, The considerable leaf mass of a mature comfrey plant, cut several times in a season, can add plenty of high-nitrogen green material to the pile. In addition, the leaves contain calcium, phosphorus, potassium, and trace minerals drawn deep from the subsoil. Just be sure there are no ripe seeds, and that no pieces of root are attached to the base of the leaves that go into the compost pile.

The leaves can also be added to potato crops as a fertilizer. After allowing them to wilt, you can use the leaves by chopping them up and placing them in a trench with main crop potatoes. As the leaves are high in potassium, they make an excellent fertilizer. Layer to a depth of 1 to 2 inches. Comfrey can also be used on other plants that benefit from high doses of potassium, like tomatoes and runner beans. It has also been used to as a top dressing around soft fruit bushes. As the leaves break down, gently cultivate them into the planting area. For more information see the British NorthWest Dahlia Society’s page about using comfrey. There is also an excellent article from Organic Gardening Magazine by Jean Nick, entitled Comfrey Power, available from the online archive.

If you have large swathes of your garden which are weedy, you can also try sheet mulch as a solution. StopWaste.org has information on how to do this. To simplify, the technique is to spread out a layer of cardboard or newspaper (at 4-6 sheets thick) and cover it with a layer of organic mulch (compost, straw, alfalfa hay--available at feed stores, woodchips, coffee grounds, etc.). Then wait 6-8 months. This is not an exact science because there are many variables, such as thickness of newspaper, type of mulch and what type of plant you're trying to kill. Perennial weeds and especially coarse grass will push through the cardboard once it starts to break down so it is critical that if and when this happens you pull the mulch back and put down more newspaper/cardboard, and then replace the mulch.

Season All Season
Date 2008-01-03
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We'd suggest, given that you are concerned for your children and pets, that you hand-weed your lawn. A little pocket knife is a great tool for doing this quickly and tidily. If you just spend a little bit of time at it a few days a week, it will go faster than you'd imagine. We recommend that you live with the clover; it is extremely difficult to eradicate.

Small dandelions are easier to pull out. The City of Seattle has excellent information about caring for lawns without pesticides, including hints about controlling dandelions. Look in the right-hand menu for additional links to lawn care information.

Here is a link to some information about a dandelion weeding tool. You can at least see what it looks like and how it works.

Season Spring
Date 2007-04-20
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Both of these herbicides are registered pesticides, and the law requires that they be used in strict accordance with the directions (and only on the weeds/pests for which they are registered). It is safer for you and the environment if you manage weed problems without the use of pesticides.

You may wish to know more about these particular pesticides. Both Casoron and Preen are pre-emergents, meaning that they work to kill seedlings before they sprout. This means they will not eliminate weeds that have already broken through the soil surface and are growing above ground.

Casoron is persistent in both soil and water (i.e., it hangs around). Its active ingredient is dichlobenil. There are numerous environmental and health concerns associated with this chemical. Dichlobenil will kill any plants which are exposed to it, and will harm beneficial soil microorganisms. Below is a fact sheet about dichlobenil from Northwest Coalition for Alternatives to Pesticides

The active ingredient in Preen is trifluralin. It is a suspected carcinogen, and is toxic to fish and aquatic life, and earthworms. Here is more information from Cornell University and Pesticide Action Network UK.

The links below provide information about alternatives to chemicals for weed control. Northwest Coalition for Alternatives to Pesticides has a page of factsheets about specific weeds and ways to manage them. Here is their page on managing weeds in garden beds.

Washington Toxics Coalition also has information on ways to handle weeds in the garden. Here is more information in a PDF file.

Before reaching for chemical weed control, it makes sense to adopt gardening practices which will help keep the weed population low. Mulch is an excellent way to control garden weeds. After you manually remove weeds from an area of your garden, apply a layer of mulch. This should suppress weed growth and help retain soil moisture. Here is what garden expert Cass Turnbull says about mulch:

Not only does mulch retain water, smother tiny weeds and weed seeds, and make it easy to pull new weeds, it is also harder for new wind-borne weed seeds to get a foothold.

Mulch can be spread anywhere from 1 inch to 4 inches thick. The thicker it is, the more effective and longer lasting. Spread it thick in big empty spaces. Spread it thin around the root zones of shrubs to allow for sufficient air exchange, especially around shallow-rooted plants like azaleas and rhododendrons. And never let mulch stay mounded up in the base or the "crown" of a plant. It can cause crown rot on some shrubs and can kill them, even a year or more later.

Source: The Complete Guide to Landscape Design, Renovation, and Maintenance, Betterway Publications,1991.

Season All Season
Date 2008-01-12
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From what I can gather, it looks like there are two broad types of common weed grasses that come up in lawns. They are annual weed grasses and perennial weed grasses. Each has a different method of control. To find out what kind of unwanted grass you have, please bring a specimen to the Hyde Herbarium at the Center for Urban Horticulture, where someone can identify your grass free of charge.

I have found several print resources that address the problem of weed grass. Unfortunately, I cannot recommend a remedy. I can, however, offer you some general information about weed grasses and remedies. Here are some selections:

For Annual Grasses:
"Most summer annual grasses can be controlled with preemergence or postemergence herbicides. Preemergence herbicides are often effective with only one properly timed application; however, in areas of severe weed pressure two applications placed six to eight weeks apart may be required for satisfactory weed control. Fenoxaprop (Acclaim) often controls summer annual grasses in cool-season turfgrass communities..."
Source: A.J. Turgeon. Turfgrass Management, Fifth Edition. 1999 p. 247.

For Perennial Grasses:
"Most perennial grasses cannot be controlled selectively in cool-season turfgrass communities. Mechanical removal or spot treatment with nonselective herbicides (principally glyphosate or glufosinate) are the only means by which most of these perennial grasses can be removed."
Source: A.J. Turgeon. Turfgrass Management, Fifth Edition. 1999. p. 249.

"The undesirable coarse perennial grasses, such as quackgrass, nimblewill, and bermuda in northern lawns, are so similar to lawn grass in behavior and physiology that no really good means of selective elimination has been developed."
Robert W. Schery. The Lawn Book. 1961 p. 151.

All Grasses:
Lastly, Taylor's Weekend Gardening Guide to Safe and Easy Lawn Care recommends mechanical weeding and then a treatment of topsoil and grass seed. 1997. p. 95.

For specific herbicide recommendations, please consult the King County Cooperative Extension Master Gardener Clinic.

Season All Season
Date 2006-11-02
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According to The Lawn Bible by David R. Mellor (Hyperion, 2003), your best defense against Poa annua (annual bluegrass) is to mow high (2 inches, usually) to shade out weed seedlings; aerate the soil to improve drainage, because weeds thrive in waterlogged soil; and let the surface of the soil dry out between waterings. If you are going to apply preemergence herbicide, this would be done in late summer to early fall.

Because of the strong trend currently to avoid use of herbicides and pesticides in lawn care due to environmental and health concerns, you may want to explore nontoxic approaches to weed management. Northwest Coalition for Alternatives to Pesticides has useful information on maintaining a lawn without chemicals.

For another good discussion of this issue, you might want to refer to the book, What the Experts May Not Tell You about Growing the Perfect Lawn by Tom Ogren (Warner Books, 2004).

The University of California, Davis Extension has a document about the management of Poa annua, including specific information on the various herbicides that have been used to treat it.

Season All Season
Date 2007-04-20
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I wonder if you are referring to horsetail, or Equisetum, which is a very persistent weed. Here are pictures and links to information:

Here is a picture, and here is another picture.

Another picture from Oregon State University Extension Service, and an article.

Here is what Ciscoe Morris said about this plant in the Seattle P-I (April 29, 2006):

Hands down, horsetail (Equisetum arvense) is the worst weed you can get in your garden. If you've got it, just be glad you weren't gardening in prehistoric times. Back then, horsetail grew to 90 feet tall and you were in danger of being stepped on by a brontosaurus while weeding.

Do what we did at Seattle University. Plant a mix of shrubs, ground covers and fast-growing perennials that are thick and tall enough to hide the horsetail. Shrubs that hide horsetail include Cistus (rockrose) Lonicera pileata (privet honeysuckle) Lonicera nitida (Box honeysuckle) and rosemary. My favorite perennial to hide horsetail is the prolific hardy Geranium oxonianum 'Claridge Druce.' It will seed all over your garden, but new seedlings are easy to remove in spring. These drought-tolerant plants look great in their own right and because they are so thick and tall, no one will see the hoards of horsetail growing within.

Washington Toxics Coalition recommends controlling it by persistently hand-pulling or hoeing the above-ground growth as soon as it appears. This will weaken the plant over time. It does die back over winter, when you could cover the affected area with black plastic (for a duration of 2 years), but even this may not be entirely successful.

An article by Irene Mills in the Fall 2008 issue of the Northwest Perennial Alliance's Perennial Post says that pulling, digging, and covering with black plastic are a waste of time. The author recommends keeping an eye out in April for emerging spore-bearing stalks, and cutting these off and disposing of them in the garbage. She suggests improving the soil texture (improve drainage, add organic matter, increase soil fertility, and in some cases increase soil pH). She recommends this guide called "Controlling Horsetail" from Swanson's Nursery, originally published in Gardens West by Carol Hall.

Season All Season
Date 2007-03-23
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Here is information from the web pages of Seattle Public Utilities. An excerpt:

Fertilize Moderately

Use "Natural Organic" or "Slow-release" fertilizer

Fertilize in September and May

How much to apply

Mow better

Fertilize for a healthy colored lawn

Test for calcium deficiency

This document may also be useful.

Here is information from Washington Toxics Coalition on lawn fertilizers. An excerpt:

Lawn Fertilizers

Choose a high quality organic fertilizer with a balance of nutrients appropriate for your soil. For example, in Western Washington, WSU Cooperative Extension recommends lawn fertilizers with NPK (nitrogen, phosphorus, potassium) in a ratio of 3-1-2. This could include 3-1-2, 6-2-4, 9-3-6, and so on. Consult local cooperative extension agencies for a recommendation in your area. You may also want to get a soil test to determine better what your soil conditions are and whether adding lime would be beneficial to adjust the soil pH. Soil tests are available through the University of Massachusetts.

Phosphorus is a serious pollutant of lakes in certain locations and its use may be regulated or discouraged. If that is the case in your area, look for low-phosphorus or phosphorus-free fertilizers.

For more information on fertilizers, see our fact sheet, Choosing Fertilizers for the Lawn and Garden (35kb PDF file).

If you would like to renovate your lawn, this is something you could do in the fall. Local garden writer Ann Lovejoy describes her method in The Handbook of Northwest Gardening (Sasquatch Books, 2003):

• Mow the existing grass as short as possible.
• Spread 1 inch of clean crushed quarter-ten gravel (not pea gravel) evenly over the entire surface.
• Spread 1 inch of compost over the gravel.
• Top-seed with a regionally appropriate blend if the lawn is thin and spotty.
• Wait 6-7 weeks before mowing again.

Should you decide to start afresh, here is information from the Master Gardeners website which discusses grass seed for Western Washington gardens.

What Grass Seed Grows Well in Western Washington?

To establish a lawn in western Washington, choose a combination of turftype tall fescue grasses and turftype perennial rye grasses. A mix that adds up to about 90% of these two grass seed types will grow well in either sun or light shade in western Washington. Turftype perennial ryegrass takes full sun and stands up to traffic. Turftype tall fescues are adapted to shadier locations. In combination, the mix works for a lawn in average light conditions. Mixes containing fine-leaved fescues or chewings fescues will also establish well. Fine-leaved fescues offer bright green color, and will take some shade, but do not take heavy use.

Many commonly-grown grass types from other areas of the United States will not thrive in western Washington's cool, dry summer climate. AVOID mixes with high concentrations of Kentucky blue grasses. DO NOT PLANT Zoysia, bermuda, dichondra, centipede, carpetgrass, St. Augustine, or mondograss. Buffalograss isn't suitable for western Washington, though it may thrive in eastern Washington.

Soil Conditions for Planting a New Lawn:

Establishing a new lawn successfully depends more on the preparation of the ground before planting than on whether the lawn choice is seed or sod. Lawn failures are often caused by poor soil conditions under the roots. Many times soil surface left for planting after new construction is infertile subsoils, with rocks, lumps, and building detritus left in it. The texture may vary from sands and gravels to heavy, poorly drained clay areas. The best soil texture for a lawn is a sandy loam, containing 60%-70% sand and 30%-40% combined silt and clay.

If the soil isn't well-drained, do not try to amend a heavy clay by dumping sand into it. Adding sand doesn't work, nor does adding gypsum. Amend the soil with organic material, which will help in creating better structure. Use compost, manure, aged sawdust, ground bark, or other organic (previously living) materials. Spread 2 inches on top of the ground and work it in thoroughly 6 to 8 inches down. Getting it completely incorporated is important, because spots of organic material in clumps may decompose and cause a low spot in the finished lawn. Rake away clods and remove large rocks and litter.

Minnesota University Extension offers the following information on best practices for caring for a shoreline lawn and garden, which includes using compost as lawn fertilizer. An excerpt:

"If possible avoid the use of chemical fertilizers. Native vegetation does not require the application of additional fertilizer. Use caution if applying fertilizers to lawns and adhere to the following guidelines:

Have your soil tested to determine how much fertilizer is needed and minimize the use of chemical fertilizers; soil test sample bags are available through the county offices of the University of Minnesota Extension Service.

Use compost or manure; this is preferable to chemical fertilizer. However, these also have the potential to damage water quality if used in excessive amounts.

If chemical fertilizers are used, select slow-release (water insoluble) forms; see recommendations for fertilizing on next page.

Water your lawn after fertilizing, but do not allow excess water to run off into surface waters.

Sweep up any fertilizer spilled on hard surfaces such as walks and driveways, instead of washing it off.

Use extra caution when applying fertilizer near surface waters; do not spread fertilizer within 75 feet of surface waters or wetlands; use a "drop" spreader and not a "cyclone" spreader to minimize the possibility of getting fertilizer directly into the water.

Never apply fertilizers to frozen ground.

Leave a natural vegetation filter strip of grass, trees, and/or shrubs next to the shoreline; another option would be to construct a berm along the shore."

You may find this general information about compost, from the City of Seattle Public Utilities and the Saving Water Partnership, of interest.

Here are additional links to lawn care methods. The first three are from the Northwest Coalition for Alternatives to Pesticides:

Taking Care of Your Lawn without Using Pesticides.

Dealing with Dandelions.

Pesticide-Free Techniques for Dealing with a Mossy Lawn.

Choosing Fertilizers for the Lawn & Garden.

Read your "Weeds"--A simple Guide to Creating a Healthy Lawn.

Season All Season
Date 2007-04-20
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Acanthus mollis, or Bear's breeches, is not listed as noxious in King County, Washington State, or on the federal list of noxious plants. This is not the same as saying it isn't potentially aggressive, although I've never heard about it being a serious problem here. It is considered invasive in parts of Australia, though.

Plants for a Future Database (a British source) offers the following information on this plant and its growing habits:
"Plants can become invasive, spreading by suckers, and they are difficult to eradicate due to their deep roots."

According to the Pacific Northwest site, Rainyside Gardeners, it is sometimes difficult to get this plant to bloom. A Washington State University Extension site says that Acanthus mollis is potentially invasive in climates warmer than ours.
"This species is classified as a groundcover in that any pieces of root cut from the original plant can easily contribute to further plant spread."

If you want to grow it but are concerned about it spreading, you could try containing the roots with an 8-inch root barrier (similar to what is used to keep running bamboo in check). On the other hand, if you have this plant and decide that you wish to be rid of it, the book Wildly Successful Plants: Northern California Gardens by Pam Peirce and David Goldberg (Sasquatch Books, 2004) says that removing every bit of root over two or three seasons of growth should get rid of the plant. If you cannot eradicate it by continually digging up each new shoot, you may have some luck using a flame weeder (with due caution and appropriate protection). Northwest Coalition for Alternatives to Pesticides describes how to use this tool.

Season All Season
Date 2008-09-25
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