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how to identify seeds in weed

What is a Weed? Tips for Weed Identification In Your Garden

Want to know how to identify weeds in your home garden? Believe it or not, the secret to weed identification is that it’s all about perspective! Read on for my tips on how to identify weeds and what to do about them. It may not be what you expect.

What Do Weeds Look Like: A Childhood Perspective

I remember picking bouquets of dandelions as a child: grabbing so many in my hand that I couldn’t keep my fingers around the flowers that kept falling out. It took some time to hone my picking skills, and sometimes the head would pop off, but luckily, there were plenty of blooms for me to practice on in the local park.

Dandelion (Taraxacum officinale) growing in the rocks.

I also remember blowing the little parachutes into the wind from a dandelion who had gone fully to seed and watching them float in the air, touching down where they would grow next. It’s a classic childhood thing to do because, for kids, the superfood dandelions are just about the most fun flower around!

Today, I’m certain that my neighbours will not mind if my son picks their dandelion blooms, and I’m equally as certain that they would cringe to see him blow the seeds into their yards.

So what is it about these sunny, yellow flowers that get people all worked up?

I mean, if you think about it, you can even buy dandelion seeds. So… are dandelions (Taraxacum officinale) weeds? And if so, what makes them weeds?

What is a Weed: A Plant Lover’s Perspective

You may be reading this and thinking “a dandelion is obviously a weed. Just look at them. They take over gardens and beautiful yards of grass. That obviously makes them a weed, right?”

If you are now scratching your head and wondering “how do I identify weeds in my yard?”, then you have come to the right place because I’m going to tell you.

A weed is simply a plant that is growing where it is not wanted.

If you have a bunch of rogue tomato or squash plants in your garden, they are called “volunteers”. However, if you have fairly hardy, native, or invasive plants growing where you didn’t plant it, that’s a “weed.” If you have a few pop up in the middle of the flower bed, that is a “wildflower.”

They are all the same thing.

Dead nettle (Lamium purpureum)

The reason weeds are seen as a garden problem at times is because they compete with plants who prefer garden space, nutrition, and water. Left to their own devices, the weeds will probably win.

They are stronger, faster-growing, and relentless in the garden. They can come back from a tiny thread of root left behind and bury themselves so deep you will lose your shovel before you get them all. Or, they can grow sideways out under rocks, pots, or landscape fabric.

The seeds can also stay dormant for hundreds of years before the right conditions allow them to germinate.

Stinging Nettle (Urtica dioica)

Weeds Aren’t Bad: There Are Many Benefits

Weeds get a bad rap, and I’ll admit, sometimes I’m not thrilled about them either (like when my bindweed tries to claim control over my garden). However, there are a few benefits to weeds:

  • They are an important food source for insects, birds, and wildlife.
  • Many are edible, tasty, nutritious, and medicinal.
  • They cover bare soil quickly, holding in water and nutrition.
  • They can also draw water and nutrients from deep in the soil via those long taproots that make them so hard to pull up.
  • Compost these weeds, and those nutrients will feed your garden.

Weed Identification: How to Identify What is a Weed in Your Garden

You can certainly search the web for weed identification and it will bring up plenty of charts. The methods I generally use don’t require any books or a computer screen, though.

In most cases, I will let the plant in question grow and see what happens. If it seems that this little seedling will soon be a monster taking over my beautiful peony, then, yoink! It’s off to the compost bin.

If it’s peppering the lawn with flowers as clover does, I’ll happily leave that for the bees to enjoy. The bees have enough problems these days without me taking their food sources away.

Chickweed (Stellaria media) -yum!

Identifying Weeds in the Vegetable Garden

In the vegetable garden, I teach children to identify weedlings before they take over the veggie plot.

Generally, if a tidy row of similar-looking greenery is growing in an orderly fashion where you planted some seeds, it’s likely cultivated. You can certainly check a photo of vegetable seedlings on the internet to confirm, but pattern goes a long way here.

Clusters of random-looking greens or sprouts where you didn’t plant seeds are probably wild plants. If you are still in doubt, the wait-and-see method works every time!

This doesn’t mean you need to let your entire garden grow to maturity before you realize that it’s just all buttercup. It’s simply the technique that I use to start identifying what I want and what I don’t want growing in the garden.

There are plenty of plants that aren’t typically characterized as weeds that I rip out of the beds just as quickly as I would some dreaded horsetail. With this, you are learning about your garden, the plants that naturalize there, and their habits.

If you identify a weed that looks beautiful when blooming that you want to keep for a short spell (like those darling forget-me-nots), just be sure to pluck that sucker from the soil before the flowers go to seed.

Enjoy it while you can, but be ruthless before you have hundreds to contend with!

But maybe you will like that too. It’s all perspective after all.

Plantain (Musa × paradisiaca) – delicious, medicinal, and a natural bandage

If you struggle with weed identification, I hope this post helped to give you confidence about knowing what is a weed and what is not.

More Reading on Wild Plants and Weeds

Want to embrace the wildness and eat some of the weeds? Check out these posts:

Resources Consulted

Fahn, A. 1990. Plant Anatomy, 4th ed. Butterworth Heinemann, Oxford, 588.

Harris, J.G. and Harris, M.W. 2001. Plant Identification Terminology, An Illustrated Glossary, 2nd Edition. Spring Lake Publishing, Spring Lake, Utah, 206 pp.

ITIS—Integrated Taxonomic Information System.

Pemberton, R.W. and Irving, D.W. 1990. Elaiosomes on weed seeds and the potential for myrmecochory in naturalized plants. Weed Science 38: 615–619.

Zomlefer, W.B. 1994. Guide to Flowering Plant Families. The University of North Carolina Press, Chapel Hill, 430 pp.


General Seed Identification

Baxter, D. and Copeland, L.O. 2008. Seed Purity and Taxonomy. Michigan State University Press, East Lansing, 719 pp.

Canadian Grain Commission. 2000. Visual Identification of Small Oilseeds and Weed Seed Contaminants, Grain Biology Bulletin No. 3. The Canadian Grain Commission, Winnipeg, Manitoba. 29 pp.

Davis, L.W. 1993. Weed Seeds of the Great Plains, A Handbook for Identification. University Press of Kansas, Lawrence, 145 pp.

Delorit, R.J. 1970. An Illustrated Taxonomy Manual of Weed Seeds. Agronomy Publications, River Falls, Wisconsin, 175 pp.

Gunn, C.R. and Ritchie, C.A. 1988. Identification of Disseminules Listed in the Federal Noxious Weed Act. United States Department of Agriculture, Agricultural Research Service, Technical Bulletin No. 1719, 313 pp.

Kirkbride, J.H., Jr, Gunn, C.R., and Dallwitz, M.J. 2006. Family Guide for Fruits and Seeds, Version 1.0.
URL: http://sbmlweb/OnlineResources/frsdfam/Index.cfm

Kulpa W. and Desowska, K. 1988. Quarantine or restricted seeds in international seed trade. Bulletin of Plant Breeding and Acclimatization Institute, Supplement Number 166: 1–98.

Martin, A.C. 1946. The comparative internal morphology of seeds. The American Midland Naturalist 36(3): 513–660.

Martin, A.C. and Barkley, W.D. 1961. Seed Identification Manual. University of California Press, Berkeley, Los Angeles, 221 pp.

Montgomery, F.H. 1977. Seeds and Fruits of Plants of Eastern Canada and Northeastern United States. University of Toronto Press, Toronto, 232 pp.

Muenscher, W.C. 1935. Weeds. MacMillan Company, New York, 577 pp.

Musil, A.F. 1963. Identification of Crop and Weed Seeds. USDA Agriculture Handbook No. 219, Superintendent of Documents, Washington, D.C., 214 pp.

Plant Protection and Quarantine, Animal and Plant Health Inspection Service, United States Department of Agriculture. 1980. Major Weed Family Identification Guide, 1st Edition. Creative Universal, Inc., Southfield, Michigan, 161 pp.

RSABG Seed Program Home. [Online database of seed photographs by John Macdonald.] Rancho Santa Ana Botanic Garden.

California Botanical

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DiTomaso, J.M. and Healy, E.A. 2007. Weeds of California and Other Western States, Volumes 1 & 2. University of California, Agriculture and Natural Resources, Publication 3488, 1808 pp.

Fuller, T.C. and McClintock, E. 1986. Poisonous Plants of California. University of California Press, Berkeley, 433 pp.

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Hickman, J.C., ed. 1993. The Jepson Manual of the Higher Plants of California. University of California Press, Berkeley, 1400 pp.

Meyer, D.J.L. and Effenberger, J. 2004. California Noxious Weed Disseminules Identification Manual. California Department of Food & Agriculture, Plant Pest Diagnostics Center, Sacramento.

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Australia Botanical

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New Zealand Botanical

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MAF Biosecurity Authority Plants Biosecurity Index. New Zealand Government.

Webb, C.J. and Simpson, M.J.A. 2001. Seeds of New Zealand gymnosperms and dicotyledons. Manuka Press, Christchurch, 428 pp.

Other USA Botanical

Agricultural Research Service, United States Department of Agriculture. 1970. Selected Weeds of the United States. Superintendent of Documents, United States Government Printing Office, Washington, D.C., 463 pp.

Agricultural Research Service, United States Department of Agriculture. 1971. Common Weeds of the United States. Dover Publications, New York, 463 pp.

Flora of North America.

Germplasm Resources Information Network — (GRIN) [Online database]. National Germplasm Resources Laboratory, United States Department of Agriculture, Agricultural Research Service, Beltsville, Maryland.

SEINet—Southwest Environmental Information Network.

The Plant List. 2010. Version 1.

The PLANTS Database. 2010. Natural Resources Conservation Service, United States Department of Agriculture, National Plant Data Center, Baton Rouge, Louisiana.

Washington State Noxious Weed Control Board.

Other Countries Botanical

Afonin, A.N., S.L. Greene, N.I. Dzyubenko, A.N. Frolov (eds.). 2008. AgroAtlas—Interactive Agricultural Ecological Atlas of Russia and Neighboring Countries.

E-Flora BC: Electronic Atlas of the Plants of British Columbia. 2008.

Flora of China.

Flora of Pakistan.

Global Invasive Species Database.

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Plants of Taiwan. 2009. [Includes online versions of Flora of Taiwan and Flora of Taiwan, 2nd. Ed.] Institute of Ecology and Evolutionary Biology, NTU.

Reed, C.F. 1977. Economically Important Foreign Weeds; Potential Problems in the United States. United States Department of Agriculture, Animal and Plant Health Inspection Service and Agricultural Research Service, Agriculture Handbook Number 498, 746 pp.

Zafar, M., Khan, M.A., Ahmad, M., and Sultana, S. 2006. Palynological and taxonomic studies of some weeds from flora of Rawalpindi. Pakistan Journal of Weed Science Research 12(1–2): 99–109.

Specific Plant Families


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Meyer, D.J.L. 1999. Seed Unit Identification in the Asteraceae. California Department of Food & Agriculture, Plant Pest Diagnostics Center, Sacramento.


Berggren, G. 2006. Atlas of seeds and small fruits of northwest-European plant species (Sweden, Norway, Denmark, East Fennoscandia and Iceland) with morphological descriptions: part 3. Salicaceae-Cruciferae. Stockholm, Swedish Museum of Natural History, 259 pp.

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Meyer, D.J.L. and Effenberger, J. 2001. Identification of Polygonaceae Seed Units. California Department of Food & Agriculture, Plant Pest Diagnostics Center, Sacramento.


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