Foraging: How to identify edible wild plant Horseweed. Abundant and easy to ID

 

Identification difficulty: Beginner 

Horseweed, also known as Erigeron canadensis and formerly as Conyza canadensis, is a widespread, native, edible wild plant in the greater Aster family, Asteraceae. In some areas it's known as fleabane, butterweed, mare's tail or colt's tail.  

It's incredibly abundant as it grows natively in the 48 continental states, and has been introduced into Alaska and Hawaii. In Canada, you can find it all throughout British Columbia and P.E.I. and along the southern edges of every Provence except Labrador, Nunavut and the Northwest Territories. It can be found throughout Mexico and in most of the non-island Central American Countries.

It's almost certainly in your neighborhood. 

Horseweed patch from my yard, early May

Horseweed gets little attention in the foraging community, with no really good reason as to why. It's easy to identify, less bitter than the well-known dandelion or plantain, more flavorful than clover, and provides more food than wood sorrel. Despite this, horseweed is only barely mentioned, while those others are brought up every season. 

Perhaps it's because horseweed has an unpleasant tendency to grow in some of the least savory of places, including out of sewer grates in the middle of dense and dirty cities. In fact, while I will often find a plant or two on my neighborhood stroll, I often find horseweed growing most densely and abundantly in urban environments: city parking lots, sewers and underneath highway overpasses. 

Horseweed is actually quite popular in the survivalist communities, though not as food! But more on that later. 

Fortunately, a large patch recently chose to grow right in my own yard! So I've finally been able to see what all the fuss is about, and, let me tell you, this is one tasty little (actually, BIG) weed!

Horseweed taste; edible and medicinal uses

When plants are quite young, 3-4 inches, you can use the whole plant. The central stem gets tough and stringy very quickly, after the plants are around 5 inches high, you will only want to use the leaves. Once the plant is over a foot high or so, you will only want to use the leaves at or near the top, the rest will be dry and flavorless. Once the plant is flowering, it's no longer good for food. 

Apparently horseweed is most commonly steeped as a tea, though I only recently tried it that way.

Horseweed can also be used as a flavorful herb, which is how I've been applying it. Simply strip the leaves off the central stalk, chop and add to your dish. I would describe the flavor as being a bit like oregano, but with a freshness like parsley, some almost citrusy brightness and, at the back of the pallet, some anise or tarragon flavor. For me this taste only ever comes at the end of the meal, which is interesting. 

Once the flower stems form the leaves are no longer flavorful, but you can harvest the flower buds. These can be added directly into dishes as a vegetable, or pickled if you like. Make sure to get the buds and not the post-bloomed flowers. 

Horseweed lends itself to Italian and Indian dishes for sure and I'm looking to branch out further in my experimentation. 

Horseweed identification

Growth and Stem features

• 

  Hairy stalk

  Horseweed grows as a single, straight central stalk, no branching until flowering
• Horseweed can grow up to 8 feet tall, but will most often flower between 4 and 5 feet, though you won't want to be harvesting when it gets that old
• When fully grown, the stalk will develop a hollow core, but again, you probably won't want to eat the plant at that stage. 
• The stalk is quite hairy, and have shallow vertical grooves or striations running up the whole length
• The leaves grow directly off the stem on slender petioles (leaf stems), no fibrous stems
• The leaves rotate around the stalk as they grow, they do not grow in opposite pairs

Horseweed leaves | Left: young leaf, still a little rounded
Center: assorted mature leaves to show variations
Right: leaf detail to show barbs

Leaf features

Hairy leaf underside and edges,
also note the veins that run parallel to the leaf edge

• Horseweed leaves are lanceolate, which is to say they are much longer than they are wide; they will become even more so as they age
• Like the stalk, the leaves also have hair, though only on the underside and around the edge of the leaf, not on the top side.
• Horseweed leaves are sometimes described as serrated (like the edge of a saw or a bread knife), but I think this is misleading; rather, they have occasional "barbs" on the leaf edges, anywhere from 2-6 per leaf, (older leaves can have 8)
• These barbs start out as small triangles, but will develop a more fish-hook shape as the leaf ages and grows larger
• One of the best identification features is the randomness of these barbs; almost every leaf will be unique in number of barbs, unique barb positioning, and unique barb size
• All leaves will have prominent veins that run parallel to the central vein, and to the leaf edges; this is easier to see on the underside of the leaves

Flowers

• Before flower buds form, horseweed will start to grow lots of small stems/branches at the top of the stalk. These stems will be 4-12" or so long, and will vary in length with the height of the plant.
• Once these stems form, the plant is no longer good for food as the leaves will become papery and flavorless
• If you are familiar with the aster family as a whole, horseweed has very typical aster flowers - the petals are so narrow they almost appear like hairs or lashes around the bloom
• The petals are white and the centers are yellow
• Each flower is about the size of an American or Canadian dime
• Once bloomed, the flowers will turn into puff heads, similar to dandelion's, but smaller

Look-a-like plants

Note: as long as you are careful about looking for hair, there are no poisonous look-a-likes for horseweed, though there may be allergens that effect some people strongly, even dangerously, on an individual basis. 

Cudweed, Gnaphalium species: Non-poisonous

This is really an unnecessary amount of hair, cudweed

Cudweed can somewhat resemble horseweed when young as it has lanceolate leaves with hairy edges, and a hairy stem, but cudweed is much, much, much more hairy than horseweed. To tell them apart, look for the center of the top new leaf growth. Even the new budding leaves will be covered in white hair. 

Lance-leaf ragweed, Ambrosia bidentata: Generally non-poisonous

One of the less-common ragweeds, Ambrosia bidentata or the lance-leafed ragweed, is named for, well, lance-like leaves. Like horseweed, lance-leaf ragweed has hairy stems and leaf edges, the leaves also have barbs. Unlikely horseweed, lance-leaf ragweed's barbs are quite deep, appearing almost like fingers. A. bidentata also has red streaks on the stem. See pic above. 

Lance-leaf ragweed is generally considered to be non-poisonous and Native Americans even ate the seeds of ragweeds, which are rich in proteins and fats. However, some individuals are known to be sensitive to this plant, and ingesting it can create a rash, throat-swelling or worse. 

Lance-leaf ragweed is found in from the Mid-Atlantic states (and CT in New England), west through the Midwestern states, NOT in the great plains states, and south to Texas. It is fairly uncommon throughout it's range, yet I seem to find it in any state I live in. 

There may be other ragweeds with lanceolate stems, but all should have deep notches in the leaf. 

Goldenrod, Solidago species: Edible

Members of the genus Solidago, called goldenrods, are incredibly common, native look-a-like species for horseweed. Goldenrods are abundantly found in every US state and throughout most of Canada and into Mexico. 

Generally speaking, Solidago species do NOT have hairy stems, though there are some exceptions. Should you come across one of these hairy goldenrods, you can still check the leaves (which feature true serrations at the edge) and grow opposite each other off the stem. 

I did a post on identifying goldenrod, here!

Additional uses for horseweed

Horseweed is popular in the survivalist community, as the largest, widest, fully grown stalks, available from the middle of summer and into early fall, can be dried and used as hand drill spindles which are an essential part of generating friction fires. With their hollow stalks, extremely long length, nearly-perfect straight growth, generally round form and lightweight but sturdy reed-like texture, horseweed is ideal for this purpose.

Contrary to common belief, you want to harvest your mature horseweed green, not dead and dried, for this making hand-drill spindles. This is because once the plant is dead it will become susceptible to softening in the rain or even the morning dew. You should dry the stalks yourself. 

I'm certainly not a survivalist expert, but if you are interested in horseweed for this purpose, there are many websites and YouTube channels to help you.

Still, it's a wonderful plant that provides us with useful parts from mid-spring all the way through mid-autumn, and definitely a plant you should learn!