This is a good time to talk about weeds. The rain has been very generous this year, bringing lots of seedlings along with it, but it can be hard to tell which are weeds and which are plants we want to keep. When sowing seeds in the ground, the safest bet is to germinate a few in a pot so you know what the seedlings look like. If that’s not an option, getting to know local weeds is a good idea.
TPF’s former director of horticulture, Madena Asbell, put together a lesson on seedlings and most of these pictures and some of the text are from her. Thanks, too, to Jacob Goetz for sharing seedling pictures!
Bad Weedling: Mustard (Brassica species)
Mustard covers much of our wild lands and is a very prolific weed. It’s best to remove mustard wherever you can.
Bad Weedling: Red-stemmed filaree (Erodium cicutarium)
These low-growing weeds have naturalized throughout the state.
Bad Weedling: Russian thistle or tumbleweed (Salsola species)
In addition to being a noxious weed, Russian thistle is a fire hazard so it is best not to let it establish on your property.
Good Seedling: California poppy (Eschscholzia californica)
Poppies are fairly easy to recognize. The very first “leaves” to emerge (the cotyledons) are slender and forked. The true leaves that follow are bluish in hue and deeply divided like the leaves of a carrot.
Good Seedling: Clarkia species
Clarkia seedlings can be recognized by the red veins and margins of the leaves on the plant on the right. Notice the weed seedling on the left. The leaves are narrower and serrated. Clarkia are a good example of how a desirable plant can become unwelcome in the garden (a weed, in other words). Most gardeners find they have to thin Clarkia seedlings or they become overrun with them.
Good Seedling: Wishbone or four o’clocks (Mirabilis laevis)
This California endemic is native to Los Angeles County and puts on a wonderful spring bloom.
Good Seedling: Yarrow (Achillea millefolium)
Seedling or weedling?
Here’s where it gets hard: telling one from another. The tidy tips seedling on the left has bright green linear (long and straight) leaves with lobed margins (edges). The unidentified weed has lanceolate (lance or arrow-shaped) leaves with serrated margins (edges) and small purple spots.
Russian thistle has needle-like leaves while California poppy has carrot-like leaves.
Chia has deeply lobed leaves with a warty surface texture. Its petiole (leaf stem) is often light purple/red and its leaf texture resembles laciniato kale. Filaree has alternating leaflets attached along a greenish-yellow petiole (leaf stem). Individual leaflets resemble cilantro or parsley.
Mustard seedling on left with a Phacelia seedling on right. Phacelia campanularia leaves often have reddish veins, margins and petioles (leaf stems). Mustards do not.
The leaves of grasses and blue-eyed grass (Sisyrinchium bellum, Iris family) look very much alike when very small. Seedlings of blue eyed grass will develop, flat overlapping leaf bases. The leaves of true grass seedlings do not form into a flat shape. You’ve probably seen enough unwanted grass seedling to recognize them in your sleep.
Seedling or … seedling?
Sometimes it can be hard to tell one seedling from another. Poppy and yarrow both have finely divided leaves so color may be the easiest way to tell them apart. Poppy is much bluer while yarrow is “spring green”.
There are many more weeds that we could cover. UC Extention has a useful online identification guide for identification. Happy weeding!
Thanks so much!!!!!
This is so helpful!
Few years ago I grew a Red-stemmed filaree (Erodium cicutarium) plant that I thought was a “something”. It got to about 4 feet tall! THX TRF
You too, eh? 😀
I thought for a while that it was rather attractive, but now that its offspring are all over the place, my enthusiasm has cooled.
You must have great soil!
Did you know that Filaree are edible? And the seeds are reportedly high in Vitamin K. https://www.eattheweeds.com/tag/filaree/
This is my life right now! As I spend my first winter tending a small community native garden plot, it’s maddening telling friend from enemy, but very educational. Thank you!
cream cups seedlings! they totally look like a grass or weed…..
Try Yarrow, California Poppy, Red-Stemmed Filaree, and Fennel all sprouting next to each other. Talk about driving me crazy! This was in a nature preserve a couple years ago, between a native plant garden and a wild-weedy area.
Chickweed…this is the bane of my existence, it’s gotten everywhere, I can’t keep up.
Chickweed is an absolutely excellent medicinal and edible herb. Best way I’ve found to get rid of them is to utilize them in the kitchen and apothecary! 😉
I don’t have words for how helpful this is to me and my wildflower plantings. So many places show only the first sprout with two leaves or the full grown plant. Having pictures and descriptions to distinguish them at weed pulling size is so helpful <3 Thank you for putting this together!
Thanks, Nic! We’re so glad this document helped you be a better native plant gardener!
I started making an identification guide for myself, so thanks for the additions! Wish the photos were bigger, though.
This is excellent. I planted native seeds and they got all mixed up, so this is helping me loosely identify my seedlings. Thank you!!!
Thank you! So helpful when you’ve planted wildflowers in an area previously overrun with weeds. I especially needed the blue-eyed grass vs grass proper. I think a further discriminator in my own case is that there is no trace if red in the blue-eyed grass seedlings, whereas the grasses common in my yard have a thread of red in the main stem.
Although one should not cultivate invasive weeds for any reason, I note that many “bad” weedlings are good eating, especially at the weeding stage, when they’rr nice and tender. In my own yard, edibles include wood sorrel, dandelion, sow thistle, chickweed, black mustard, and purslane. I’ve been adding them to braised vegetables, but they are also delicious in salads.
Really helpful link for many people but unfortunate you don’t talk about some of the benefits of the ‘bad’ weeds, specifically the fact that every one mentioned is an excellent edible…eat your invasives!